Tag Archives: Webb

Webb unearths proof of functioning supermassive black holes in Messier 83

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Space Telescope Sciences Scientists According to a team of astronomers led by science scientists at the Sciences, highly ionized neon gas detected in the center of the Spiral Galaxy Messier 83 by a mid-inphrase instrument (MIRI) mounted on the NASA/CSA James Webb Space Telescope.

This web image shows the Messier 83. Image credits: NASA/ESA/CSA/Webb/A. Adamo, Stockholm University/Feast JWST Team.

Messier 83 is a spiral galaxy, a magnificently designed rod 15 million light years away from the southern constellations of Hydra.

Also known as the Southern Pinwheel Galaxy, M83, NGC 5236, Leda 48082, and UGCA 366, the galaxy is about twice as small as the Milky Way.

Messier 83 was like that I discovered it By French astronomer Nicholas Louis des Lacaille on February 17, 1752.

Its apparent size is 7.5, and is one of the brightest spiral galaxies in the night sky. It is the easiest way to observe using binoculars in May.

This is a prominent member of the galaxy group known as the Centaurus A/M83 group, counting the Dusty NGC 5128 (Centaurus A) and the irregular Galaxy NGC 5253.

Messier 83 has been a mystery for a long time. Large spiral galaxies often host active galactic nuclei (AGN), but astronomers have struggled to see what Messier 83 has been the case for decades.

Previous observations suggested that if a super-large black hole exists there, it must be dormant or hidden behind thick dust. However, new Webb observations reveal signs that suggest that this is not the case.

“The discovery of highly ionized neon emissions in the nucleus of the M83 was unexpected,” said Dr. Svea Hernandez, an astronomer with an ESA aura at the Institute of Space Telescope Science.

“These signatures require a lot of energy to be produced, rather than what a normal star can produce.”

“This strongly suggests the existence of a previously elusive AGN.”

“Before Webb we didn’t have the tools to detect such faintly ionized gas signatures at the nucleus of the M83.”

“Now, with incredible mid-red sensitivity, we can finally explore these hidden depths of the galaxy and uncover what we once couldn’t be seen.”

Webb’s mid-infrared observation allowed astronomers to peer into the dust and detect signs of highly ionized gases in small masses near the galactic nucleus.

The energy required to create these signatures is significantly higher than what supernovae and other great processes can offer, making AGN the most likely explanation.

However, alternative scenarios such as extreme shock waves in interstellar media are still under investigation.

“Webb is revolutionizing understanding of galaxies,” says Dr. Linda Smith, an astronomer at The Space Telescope Science Institute.

“For years, astronomers have been searching for the M83 black hole without success. Now we have compelling clues that could finally exist.”

“This finding shows how Webb is making unexpected breakthroughs.”

“Astronomers thought they had ruled out AGN on the M83, but now there is fresh evidence that they will challenge past assumptions and open new paths for exploration.”

Survey results It will be displayed in Astrophysical Journal.

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Svea Hernandez et al. 2025. JWST/MIRI detection [Ne v] and [Ne vi] M83: Evidence of a long-required active galactic nucleus? APJ 983, 154; doi:10.3847/1538-4357/adba5d

Source: www.sci.news

Webb captures stunning new image of Planet Nebula NGC 1514

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The two central stars of the NGC 1514 are displayed as one of the images from the NASA/ESA/CSA James Webb Space Telescope, forming this scene for thousands of years and maintaining it for thousands more.

This web image shows the planetary nebula NGC 1514. Image credits: NASA/ESA/CSA/STSCI/Michael Ressler, JPL/Dave Jones, IAC.

NGC 1514 It is about 1,500 light years away from the Taurus sign.

The object, also known as the Crystal Ball Nebula, was discovered on November 13th, 1790 by German and British astronomer William Herschel.

He pointed out that NGC 1514 was the first deep sky object that really looked cloudy. He couldn’t resolve what he saw on individual stars in the cluster, like other objects he catalogued.

The ring around NGC 1514 was discovered in 2010, but Webb is now allowing astronomers to comprehensively examine the nature of the turbulent flow of this nebula.

“This scene has been formed for at least four,000 years and will continue to change over a thousand years,” Webb Astronomers said in a statement.

“In the center there are two stars that appear as one in Webb observations, caused by vivid diffraction spikes.”

“The star follows a solid, elongated nine-year orbit, covered in an arc of dust, represented by orange.”

“One of these stars, once a massive scale several times larger than our sun, played the lead role in producing this scene.”

“When the outer layers of the star were exhausted, only the hot, compact core was left behind.”

“As a white dwarf star, its winds rose sharply and weakened, and could have blown away the material into a thin shell.”

New Webb observations show that the nebula is at a 60-degree angle, which makes it appear that the can is poured in, but it is much more likely that the NGC 1514 took the shape of an hourglass and dropped the edges.

“Look for pinchwaist hints near the top left and bottom right. The dust is orange and drifts in a shallow V-shaped shape,” the astronomer said.

“When the star reached its peak of losing material, our peers may have become very close and have had these unusual shapes.”

“Instead of creating a sphere, this interaction may have instead formed a ring.”

“The NGC 1514’s outline is most clear, but the hourglass also has some sides of the 3D shape.”

“Look for a dim, translucent orange cloud between the rings that give to the nebula body.”

Nebula’s two rings are illuminated unevenly by Webb’s observations, appearing to be more diffused at the bottom left and top right.

Researchers believe that the rings are primarily made up of very small dust grains. This will get hot enough for Webb to detect when hit by ultraviolet rays from a white star star.

“In addition to dust, Webb revealed oxygen in its chunky pink center, especially at the edges of the bubbles and holes,” they said.

Source: www.sci.news

Webb finds a Milky Way-like spiral galaxy in ancient universes

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope discovered a very ancient grand design spiral galaxy that existed just a billion years after the Big Bang. Named Zhúlóng (Torch Dragon), this galaxy is the most distant bulging disc galaxy candidate for which spiral arms have been known to date.

This image of Zhúlóng, the furthest spiral galaxy discovered to date, shows its very well-defined spiral arm, old bulge in the middle, and a large star-forming disc resembling the structure of the Milky Way. Image credits: NASA/CSA/ESA/M. Xiao, University of Geneva/G. Brammer, Niels Bohr Institute/Dawn JWST Archive.

Large spiral galaxies like our Milky Way are expected to take billions of years to form.

For the first billion years of universe history, galaxies are considered small, chaotic and irregular.

However, Webb is beginning to reveal very different photos.

Telescope deep infrared imaging reveals surprisingly large and well-structured galaxies much earlier than previously expected.

Among these new findings is Zhúlóng, the most distant spiral galaxy candidate ever identified, seen at a redshift of 5.2.

Despite this early period, galaxies exhibit surprisingly mature structures. Old bulge in the middle, large star-forming discs, spiral arms – a feature usually found in nearby galaxies.

“What stands out for Zhúlóng is both how similar it is to the Milky Way, its shape, size and star mass,” says Dr. Mengyuan Xiao, a postdoctoral researcher at Unige.

“The disc spans over 60,000 light years, comparable to our own galaxy, and the star contains over 100 billion solar masses.”

“This makes it one of the most persuasive Milky Way analogs discovered at such an early age, raising new questions about how a large, ordered spiral galaxy will form right after the Big Bang.”

The Zhúlóng Galaxy was discovered as part of a panoramic investigation.

“The findings highlight the possibility of purely parallel programs to reveal rare, distant objects that stress-test galaxy formation models,” says Dr. Christina Williams, a No-Arab astronomer and lead researcher of the Panorama Program.

Spiral structures were previously thought to take billions of years, but large galaxies were not expected to exist much later in the universe.

“The discovery shows that Webb is fundamentally changing the way we see the universe in its early days,” says Professor Pascal Oesch, an astronomer at Unige and a co-researcher of the Panorama Program.

a paper The discovery was published in the journal today Astronomy and Astrophysics.

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Mengyuan Xiao et al. 2025. Panorama: Discovery of a super gentle grand design spiral galaxy from z to 5.2. A&A 696, A156; doi:10.1051/0004-6361/202453487

Source: www.sci.news

Webb discovers potential signs of life in the atmosphere of K2-18b

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope detected chemical fingerprints of dimethyl sulfide (DMS) and/or dimethyl disulfide (DMD) in the atmosphere of the hyperexterrestrial K2-18b. On Earth, DMS and DMD are produced solely by life, primarily microorganisms such as marine phytoplankton. While unknown chemical processes may be the source of these molecules in the atmosphere of K2-18B, the results are the most powerful evidence that life may exist on planets outside of spores.

Impressions of the artists of Super Earth ExoPlanet K2-18b. Image credit: A. Smith/N. Mandhusudhan.

K2-18 is a red dwarf about 111 light years away from Leo’s constellation.

The star, also known as Epic 201912552, hosts two giant deplanets: K2-18B and K2-18C.

The K2-18B, first discovered in 2015, has a radius of 2.6 times, about 8.6 times.

The planet orbits the star every 33 days at a distance of about 0.15 Au and has an Earth Similarity Index of 0.73.

It receives 1.28 times the intensity of the Earth’s light, and its equilibrium temperature is 2 degrees Celsius (28 degrees Fahrenheit).

Previous observations of K2-18b identified methane and carbon dioxide in its atmosphere. This was the first time a carbon-based molecule was discovered in the atmosphere of an exoplanet in a habitable zone.

These results were consistent with Hycean’s global predictions. This is an exoplanet covered with habitable oceans under a hydrogen-rich atmosphere.

However, another weak signal suggested that something else could happen with the K2-18B.

Transmission spectra of K2-18B using Webb’s Miri Spectrograph. Image credit: A. Smith/N. Mandhusudhan.

“I wasn’t sure if the signal I saw last time was due to DMS, but that hint alone was so exciting that I used a different instrument to make it look different from the Webb,” said Professor Nikku Madhusudhan, an astronomer at Cambridge University.

Previous tentative DMS inferences were made using Webb’s Niriss (near-infrared imager and slitless spectrograph) and Nirspec (near-infrared spectrograph) instruments.

New independent observations used Webb’s Miri (medium-infrared instrument) in the mid-infrared (6-12 microns) range.

“This is independent evidence using different wavelength ranges of light that do not overlap with previous observations, and not with previous observations. The signal has become stronger and more clear,” Professor Madhusudhan said.

“It was incredible to see results emerge and remain consistent through extensive independent analysis and robustness testing,” added Dr. Måns Holmberg, an astronomer at the Institute of Space Telescope Science.

DMS and DMD are molecules from the same family of chemicals, and both are predicted to be biosignatures.

Although both molecules have spectral features that overlap the observed wavelength range, further observations can help distinguish between the two molecules.

However, the concentration of atmospheric DMS and DMD in K2-18B is very different from Earth, which is generally less than a billionth of a volume.

In the K2-18B, they are estimated to be thousands of times stronger.

“The outcome is exciting, but it’s important to get more data before you claim that life has been discovered in another world,” Professor Madhusdan said.

“The inference of these biosignal molecules raises deep questions about the processes that may be producing them,” says Dr. Subajit Sarkar, an astronomer at Cardiff University.

“They’re the most popular and most popular,” said Dr. Savvas Constantinou, an astronomer at the Institute of Astronomy at Cambridge University.

“It’s important that we are deeply skeptical of our own outcomes, because once again, it’s only through testing and testing that we can get to where we are confident in them. That’s how science works,” Professor Madhusudhan said.

study It was released today Astrophysics Journal Letter.

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Nick Madhusdan et al. 2025. New constraints of atmospheric DMS and DMD of K2-18B from JWST millimeters. apjl 983, L40; doi: 10.3847/2041-8213/ADC1C8

Source: www.sci.news

Webb telescope measures size of asteroid 2024 YR4 and captures images of potential danger

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The destructive forces of shocking asteroids are estimated primarily by knowledge of their size. Near Earth Asteroid 2024 YR4 reached a peak 2032 impact probability on Earth at 3%, motivated the desire to determine its size. Due to its infrared capabilities, the NASA/ESA/CSA James Webbspace Telescope is uniquely suited to such evaluations. Johns Hopkins University astronomer Andrew Livkin and his colleagues used two Webb instruments to measure the diameter for 2024.

These web images show asteroid 2024 YR4 near Earth. Image credits: NASA/ESA/CSA/STSCI/A. RIVKIN, JHU/APL.

2024 yr4 On December 27, 2024, the Asteroid Terrestrial Impact of Río Hurtado was discovered by the Last Alert System (Atlas) station.

The asteroid took a close approach to Earth at a distance of 828,800 km (515,000 miles) two days before its discovery.

Initial observations from the 2024 YR4 showed that the diameter was 40-90 m (131-295 ft).

Dr. Eric McLennan, an astronomer at the University of Helsinki, said:

“However, thermal radiation at infrared wavelengths is a direct indicator of size.”

Dr. Livin, Dr. McLennan and his colleagues observed using the 2024 YR4 Webb’s Near-Infrared Camera (nircam) Mid-infrared instrument (Milli).

Nircam data reflects light, while Miri’s observations show heat light.

“The observations were taken to study the thermal properties of the 2024 YR4, including how quickly it heats and cools at the current distance from the sun, and how hot the heat is,” the astronomer said.

“These measurements show that this asteroid does not share the properties observed on the larger asteroid.”

“This could be a combination of its fast spin and a lack of fine sand on its surface.”

“More research is needed, but this is thought to coincide with surfaces dominated by rocks that are roughly below the size of a fist.”

New Webb observations show that the asteroid measures approximately 60 m (197 feet).

“The 2024 YR4 has been the smallest object that Webb has ever targeted and is one of the smallest objects that directly measure its size,” the researchers said.

“New observations from Webb provide unique information about the size of the YR4 in 2024, as well as complement the ground-based observations of the object’s location to improve understanding of the object’s trajectory and future trajectory.”

Team’s Survey results It was published in AAS research notes.

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As Livin et al. 2025. JWST observation of potentially dangerous asteroid 2024 YR4. res. Note AAS 9, 70; doi:10.3847/2515-5172/ADC6F0

Source: www.sci.news

Webb discovers the highly elusive “Einstein Ring”

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Light from the very distant spiral galaxy was bent and expanded by the gravity of the members of the Galaxy Cluster SMACSJ0028.2-7537 to form a ring-like structure known as the Einstein ring.

This composite image combines data from Webb’s near-infrared camera (Nircam), Hubble’s Widefield Camera 3 (WFC3), and advanced cameras for survey (ACS) equipment, showing Einstein’s rings around the elliptical galaxy of the Galaxy Cluster. Image credits: NASA/ESA/CSA/Webb/G. Mahler.

Einstein RingAlso known as Einstein-Chwolson Rings or Chwolson Rings, occurs when light from very distant objects bend around a large intermediate object.

“This is possible because space-time, the fabric of the universe itself, is bent by mass, so light passing through space and time is also bent,” said Guillaume Mahler, an astronomer at the University of Ligiju and a colleague.

“This effect is too subtle to observe at a local level, but dealing with the curvature of light on a huge astronomical scale can make it clearly observable.”

“When light from one galaxy is bent around another galaxy or cluster of galaxies.”

“If the lensed and lens objects are perfectly aligned, the result is a unique Einstein ring.”

“This will appear as a complete circle or a partial circle of light around the lens object, depending on the accuracy of the alignment.”

“Objects like this are the ideal laboratory for studying how galaxies are so faintly far away.”

New images were captured by Webb’s Nircam (near infrared) instrument As part of Powerful lens and cluster evolution (slice) investigation.

“The lens galaxy at the heart of this Einstein ring is an oval galaxy that can be seen by the galaxy’s bright core, smooth, uncharacteristic body,” the astronomer said.

“This galaxy belongs to a galaxy cluster named smacsj0028.2-7537.”

“Galaxies with lenses wrapped in elliptical galaxies are spiral galaxies.”

“The image is distorted as the light travels around the galaxy in its path, but the individual star clusters and gas structures are clearly visible.”

Source: www.sci.news

Webb discovers Lyman-Alpha emissions from ancient galaxy in early universe

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The light of Lyman Afa from Jades-GS-Z13-1 took us nearly 13.47 billion to contact us, as it dates back just 330 million years from the Big Bang.

This image shows the Jades-GS-Z13-1 (middle red dot) imaged with Webb’s near-infrared camera (Nircam) as part of the Jades program. Image credits: NASA/ESA/CSA/WEBB/STSCI/JADES COLLABORATION/BRANT ROBERTSON, UC SANTA CRUZ/BEN JOHNSON, CFA/Sandro Tacchella, Cambridge/Phill Cargile, CFA/J. Witstok, P. Jakobsen & A. Pagan, Stsci/M. Zamani, Esa & Webb.

NASA/ESA/CSA James Webb Space Telescope’s key scientific goal was to see more than ever before the distant past of our universe, when the first galaxy formed after the Big Bang.

This search has already led to record-breaking galaxies when observing programs such as the JWST Advanced Deep Deep Alactic Survey (Jades).

Webb’s extraordinary sensitivity to infrared also opens up a whole new path for research into when and how such galaxies were formed, and their impact on the universe of the time known as Cosmic Dawn.

Astronomers studying one of these very early galaxies have been discovered in a spectrum of light that challenges our established understanding of the early history of the universe.

The Jades-GS-Z13-1 (GS-Z13-1 for short) was discovered in images taken by Webb’s Nircam (near-infrared camera) as part of the Jades program.

Dr. Roberto Maiolino and colleagues at the University of Cambridge and London used galaxy brightness with various infrared filters to estimate the redshift that measures the distance of a galaxy from Earth, based on how light stretches along the path of a space.

NIRCAM imaging resulted in an initial redshift estimate of 12.9. In an attempt to confirm that extreme redshift, astronomers observed the galaxy using Webb’s near-infrared spectrometer (NIRSPEC) instrument.

The resulting spectrum confirmed that the redshift was 13.0. This is the equivalent of a galaxy seen just 330 million years after the Big Bang, the current 13.8 billion-year-old minority in the universe.

However, unexpected features also stood out. One is the wavelength of light of a particular distinct bright wavelength, identified as Lyman alpha radiation emitted by hydrogen atoms.

This emission was far stronger than astronomers who thought they could be possible at this early stage of space development.

“The early universe was soaked in a thick mist of neutral hydrogen,” Dr. Maiolino said.

“Most of this haze was lifted in a process called reionization, which was completed about a billion years after the Big Bang.”

“The GS-Z13-1 shows the incredibly clear and Telltail signature of the Lyman Alpha radiation, which can only be seen after the surrounding mist has been fully lifted,” he said.

“This result was completely unexpected by early galaxy formation theories, which surprised astronomers.”

“Before and during the reionization, the enormous amount of neutral hydrogen mist surrounding the galaxy blocked the ultraviolet rays of released energy, like the filtration effect of colored glass.”

“Until sufficient stars were formed and the hydrogen gas could ionize, such light, including Lyman Alpha radiation, could not escape these fledgling galaxies and reach Earth.”

“According to Lyman Alpha radiation from this galaxy has therefore had great significance in our early understanding of the universe.”

“We’ve seen a lot of people who have had a lot of trouble with the world,” said Dr. Kevin Hayneline, an astronomer at the University of Arizona.

“We could have thought that early universes were covered in dense mists that would be very difficult to find even a powerful lighthouse peering through, but here, beams of light from this galaxy penetrate the veil.”

“This fascinating emission line has a major impact on how and when the universe has been reionized.”

The source of GS-Z13-1’s Lyman Alpha radiation from this galaxy is yet to be known, but it may contain the first light from the earliest generation of stars formed in the universe.

“The large bubbles of ionized hydrogen surrounding this galaxy may have been created by the star’s unique population, much larger, hotter and brighter than the stars formed at the later epoch, and perhaps representative of the first generation of stars, said Dr. Joris Wittok, an astronomer at Cambridge and Appenhagen University.

“The powerful active galactic nucleus (AGN) driven by one of the first super-large black holes is another possibility identified by our team.”

Team’s Survey results Published in the March 26th issue of the journal Nature.

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J. Wittstock et al. 2025. We witness the onset of reionization with Lyman-α ejection in the redshift13. Nature 639, 897-901; doi:10.1038/s41586-025-08779-5

Source: www.sci.news

Webb captures Aurorae on Neptune for the first time while detecting trihydrogen

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Emission from trihydrogen cations of large atmospheres flames (h3+) It has been used for over 30 years to study the global interactions of Jupiter, Saturn and Uranus with the surrounding space environment, revealing the process of aurora formation. However, despite repeated attempts, and against models that predict it should exist, this ion has proven elusive in Neptune. Currently, using observations from the NASA/ESA/CSA James Webspace telescope, astronomers have detected Neptune’s trihydrogen cations and distinct infrared South Aurorae.

This composite image, created using data from the NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webbspace Telescope, shows the aurora activity (cyan bevel) in Neptune. Image credits: NASA/ESA/CSA/STSCI/HEIDI HAMMEL, Aura/Henrik Mellin, University of Northumbria/Leafletcher, University of Leicester/Stefanie Millam, NASA-GSFC.

“In the past, astronomers have seen appetizing hints for Aurora’s activities in Neptune,” said Henrik Mellin, an astronomer at Northumbria University and his colleagues.

“However, imaging and confirmation of Aurorae in Neptune has been avoiding astronomers for a long time despite successful detections on Jupiter, Saturn and Uranus.”

“Neptune was a missing part of the puzzle when it came to detecting the giant planet of the solar system, Aurorae.”

In this study, the authors analyzed the obtained data. Webb’s Near-Infrared Spectroscopy (NIRSPEC) June 2023.

In addition to the image of the planet, astronomers have characterized the composition and acquired spectra to measure the temperature of the planet’s upper atmosphere (ionosphere).

They discovered a very prominent efflux system indicating the presence of trihydrogen cations.

“In Neptune’s Webb image, the glowing aurora appears as a spot, represented by cyan,” the astronomer said.

“The aurora activity seen in Neptune is markedly different from what we are used to seeing here on Earth, or even Jupiter and Saturn.”

“Instead of being trapped in the north and south poles of the planet, Neptune’s aurora is located in the mid-latitudes of the planet. Think about where South America is on Earth.”

“This is due to the strange nature of Neptune’s magnetic field, originally discovered by NASA’s Voyager 2 in 1989, tilting 47 degrees from the planet’s axis of rotation.”

“The activity of the aurora is based on where the magnetic field converges into the planet’s atmosphere, so Neptune’s aurora is far from the rotating pole.”

“The groundbreaking detection of Neptune’s Aurorae helps us understand how Neptune’s magnetic fields interact with particles flowing through far-flung areas of the solar system.

Researchers were also able to measure the temperature above the Neptune atmosphere for the first time since the flyby of the Voyager 2.

Their results suggest why Neptune’s Aurorae remained hidden from astronomers for a long time. The upper atmosphere of the Neptune was cooled several hundred degrees.

For many years, astronomers have predicted the strength of Neptune Aurorae based on temperatures recorded by Voyager 2.

“A rather cold temperature would result in a very prominent aurorae,” the scientist said.

“This cold temperature could be the reason why Neptune’s Aurorae remains undetected for a long time.”

“Dramatic cooling suggests that even though Earth is more than 30 times more seated from the Sun compared to Earth, this area of ​​the atmosphere can change dramatically.”

result Today I’ll be appearing in the journal Natural Astronomy.

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H. Merin et al. Discovery of h3+ JWST and Neptune’s infrared aurorae. Nut AthlonPublished online on March 26th, 2025. doi:10.1038/s41550-025-02507-9

Source: www.sci.news

Discovering Aurora on Neptune for the First Time with NASA’s Webb Telescope

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The Northern and Southern Lights Vermillion, Amethyst, and Jade Ribbons are some of the most distinctive features of the Earth. However, our planet has no monopoly of the Aurora. Scientists spy on them throughout the solar system, weaving the Martian sky into Saturn, Jupiter and even some of Jupiter’s fiery softening.

The light shines in the sky Uranus too. However, the aurora around Neptune, the farthest planet of our Sun, has long escaped astronomers.

That was changed by the powerful infrared equipment installed in the James Webb Space Telescope. In a study published in the journal on Wednesday Natural Astronomy scientists reveal unique auroras spilling on either side of Neptune’s equator. This contrasts with the sparkling Gossamers, arcing at Poles in other worlds.

Astronomers are excited that the Aurora Hunting Quest has been completed over decades. “Everyone is very excited to prove it’s there, as we thought,” he said. Rosie Johnson an astrophysics researcher at Aberystwyth University in Wales who was not involved in new research.

The discovery allows scientists to study previously out-of-reach aspects of Neptune. “They use the aurora to understand the shape of the magnetic field on planets looking at the invisible,” he said. Karl Schmidt Boston University planetary astronomers were not involved in new research.

Each world produces aurora differently, but it is basically the same. Energy particles (often from the sun, but sometimes from the eruption of a lunar volcano) hit the atmosphere and bounce back the gas. The collision of the particles causes a temporary flash of light. And if there is a magnetic field in the world, it will guide the position…

Luckily, the Webb Telescope, released in 2021, came to rescue.

Heidi Hammel Another astronomer of the University Association for Astronomical Studies and the author of the research, has been studying Neptune since the 1980s. She said that if Webb “is powerful enough to see the early galaxies of the universe, it would be strong enough to see something like Neptune’s Aurorae.” “And by Golly, that was the case.”

Using the telescope’s near-infrared spectrometer, astronomers captured Neptune’s infrared aurora in June 2023. This is because Neptune has an unstable magnetic field tilted to 47 degrees from the planet’s spin axis.

New Webb observations also reveal why Neptune’s Auroras has never been visible until now. Almost 40 years ago, Voyager 2 recorded a temperature of about 900 degrees Fahrenheit in the Neptune’s upper atmosphere. However, the Webb telescope shows that the temperature has dropped nearly 200 degrees. This low temperature means that the aurora is a dimmer.

In fact, Neptune’s Aurora said, “It’s less than 1% of the expected brightness and explains why I’ve never seen it before.” James O’Donohew a planetary astronomer at the UK’s Reading University and one of the authors of the study. “But that means we have a new mystery in our hands now. How did Neptune get so cold?”

Neptune’s Strange Light Show detection may bring your answers closer.

“The Aurora is like a TV screen,” he said. Lee Fletcher a planetary scientist at the University of Leicester in the UK and one of the authors of the study. They said, “We are able to see the delicate dance of the magnetosphere processes.

Source: www.nytimes.com

Webb discovers Herbig Halo objects with tornado-like characteristics

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Using Nircam and Miri instruments installed in the NASA/ESA/CSA James Webb Space Telescope, astronomers created high-resolution images Herbig-Haro Object 49/50 (HH 49/50) is located approximately 630 light years away from the constellation of Chamaleon.

Webb observed Herbig Halo 49/50 in high resolution near-infrared light with Nircam and Miri Instruments. Image credits: NASA/ESA/CSA/STSCI.

The Herbig-Haro object is a small bright patch of nebula associated with protostals in the star-forming region.

These structures were first observed in the 19th century by American astronomer Sherburn Wesley Burnham, but were not recognized as a distinct type of ejection nebula until the 1940s.

The first astronomers to study them in detail were George Harbigue and Guillermo Halo, and they were later named.

Herbig Halo objects are formed in very specific circumstances. Hot gas discharged by the newborn star collides with the gas, hitting it at a speed of up to 250,000 kmh (155,000 mph), creating a bright shock wave.

They come in a wide range of shapes. The basic configuration is usually the same. Twin jets of hot gases are ejected in the opposite direction from the forming stars and flow through interstellar space.

“When NASA’s Spitzer Space Telescope observed it in 2006, scientists called the HH 49/50 The Cosmic Tornado because of its helical appearance, but they were unsure about the nature of the fuzzy object at the tip of the “tornado.”

“Because of the high resolution of imaging, Webb provides a different visual impression of HH 49/50 by revealing fine features of impacted regions during the runoff, revealing fuzzy objects as distant spiral galaxies and displaying the oceans of distant background galaxies.”

https://www.youtube.com/watch?v=0BDZS0IHK7Y

The HH 49/50 is part of the Chamaeleon I Cloud Complex, one of the closest active star-forming regions.

“This cloud complex is likely to resemble the environment our Sun formed,” the astronomer said.

“Previous observations of the region show that HH 49/50 runoff is away from us at a rate of 100-300 km per second, and is just one feature of the larger runoff.”

“Webb’s Nircam and Miri’s HH 49/50 observations lash out on the area with the locations of shining hydrogen molecules, carbon monoxide molecules, and dust particles represented by orange and red.”

New Webb observations probe small spatial scale details that help astronomers model the properties of jets and understand how they affect the surrounding materials.

“The arc-shaped feature of the HH 49/50 refers to the source of this spill, similar to the water wake created by speeding boats,” the researchers said.

“Based on past observations, scientists suspect that the Protostal, known as the Cederblad 110 IRS4, is a plausible driver of jet activity.”

“The CED 110 IRS4 is a Class I Protostal, located about 1.5 light years from HH 49/50.”

“Class I Protostals are young objects (tens of thousands to a million years ago) at primetime when earning Mass.”

“They usually have an identifiable disc of the material surrounding it.

“Scientists have recently studied this protostal and used Webb’s Nilkah and Milli observations to obtain inventory of the ice composition of its environment.”

“Those detailed webb images of the HH 49/50 arcs can more accurately identify the orientation to the jet source, but not all arcs return in the same direction.”

“There is an interesting outcrop feature (in the top right of the main runoff) that could be another accidental accident of another runoff associated with slow precession of intermittent jet sources, for example.”

“Or alternatively, this feature could be the result of a major spill breaking apart.”

“The accidental galaxy at the tip of HH 49/50 is a much more distant, troublesome spiral galaxy.”

“There is a prominent central bulge, represented in blue, indicating the position of the old stars.”

“The bulge also gives hints from the sidelobes that suggest this could be a thin group.”

“The reddish masses within the spiral arm indicate a warm dust location and a group of formed stars.”

“The galaxies will show sheltered bubbles in these dusty areas, similar to the nearby galaxies Webb observed as part of the Phangs programme.”

“Webb captured these two unrelated objects with a lucky alignment.”

“For thousands of years, the edge of the HH 49/50 has moved outwards, eventually appearing to hide a distant galaxy.”

Source: www.sci.news

Webb successfully captures images of several massive exoplanets orbiting two youthful stars

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Astronomers using Near-infrared camera (NIRCAM) NASA/ESA/CSA James Webb Space Telescope equipped and captured corona graphic images of the HR 8799 and 51 Eridani Planetary Systems. These observations revealed HR 8799 and four known gas giants around 51 Eridani. They also revealed that all HR 8799 planets are carbon dioxide-rich.

This Webb/Nircam image shows the multiplanet system HR 8799. Image credits: NASA/ESA/CSA/STSCI/W. BALMER, JHU/L. PUEYO, STSCI/M. PERRIN, STSCI.

HR 8799 is a star from 30 million years ago, about 129 light years away from the Pegasus constellation.

Hosts large chip disks and four supergipers: HR 8799b, c, d, and e.

Unlike most exoplanet discoveries inferred from data analysis, these planets are seen directly via ground telescopes.

“We have shown that the atmosphere of these planets has quite a lot of heavy elements, such as carbon, oxygen and iron.

“Given what we know about the stars, it's likely that it indicates that they were formed through Core landing this is an exciting conclusion for the planet we can see firsthand. ”

The planets within HR 8799 are still hot from the formation of the turbulent, ejecting a large amount of infrared rays that provide valuable data about how scientists formed.

Giant planets can take shape in two ways. Like giants in the solar system, by slowly building heavy elements that attract gas, or the particles of gas rapidly merge into giant objects from a cooling disk of a young star made of the same kind of material as the stars.

The first process is called core accretion and the second is called disk instability.

Knowing which formation models are more common can provide clues to scientists distinguish the types of planets they have found in other systems.

“Our hope in this type of study is to understand our own solar system, life and ourselves, in comparison to other exoplanet systems.

“We want to take photos of other solar systems and see how they look similar or different from us.”

“From there we can feel how strange or normal our solar system is.”

This Webb/Nircam image shows the 51 Eridani system. Image credits: NASA/ESA/CSA/STSCI/W. BALMER, JHU/L. PUEYO, STSCI/M. PERRIN, STSCI.

51 Eridanus is located approximately 97 light years from Earth in the constellation of Eridanus.

51 If called ERI, C ERIDANI, or HD 29391, the star is only 20 million years old and by astronomy standards it is merely a toddler.

Host one giant planet, 51 Eridani B. It orbits the star at a distance of approximately 13 AU (astronomical units), equivalent to that of Saturn and Uranus in the solar system.

Images of HR 8799 and 51 rib ticks were made possible by Webb's Nircam Coronagraph.

This technique allowed astronomers to look for infrared rays emitted by planets at wavelengths absorbed by a particular gas.

They discovered that the four HR 8799 planets contain more heavy elements than previously thought.

“There is other evidence suggesting these four HR 8799 planets formed using this bottom-up approach,” says Dr. Laurent Puueyo, an astronomer at the Institute of Space Telescope Science.

“How common is this on planets we don't know yet?

“We knew that Webb could measure the colour of outer planets in a directly imaged system,” added Dr. Remi Somer of the Institute of Space Telescope Science.

“We waited for 10 years to ensure that the finely tuned operations of the telescope had access to the inner planet.”

“We now have results and we can do some interesting science.”

Survey results It was published in Astronomy Journal.

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William O. Balmer et al. 2025. JWST-TST High Contrast: Living on the Wedge, or Nircam Bar Coronagraph reveals CO2 HR 8799 and 51 ERI extracts atmosphere. AJ 169, 209; doi:10.3847/1538-3881/ADB1C6

Source: www.sci.news

Webb skillfully depicts the intricate details of Lynds 483

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Two young protostars are responsible for the sparkling ejection of orange, blue, and purple glowing gas and dust in this colorful dark clouds 483 on NASA/ESA/CSA James Webb Space Telescope.

This webb image shows part of Lynds 483. Image credits: NASA/ESA/CSA/STSCI.

Lynds 483 It’s almost arranged 200 persec (652 light years) Separately in the constellations of Serpen.

This object is named after American astronomer Beverly T. Lyns. Published An extensive catalogue of “dark” and “bright” nebulae from the early 1960s.

“For tens of thousands of years, the central Protostar Webb’s astronomer said in a statement.

“When a recent emission hits an older one, the material crouches and spins around based on the density of what is collision.”

“Over time, these emissions and chemical reactions within the surrounding clouds have produced a range of molecules, such as carbon monoxide, methanol, and several other organic compounds.”

“The two protostars in charge of this scene are at the heart of the hourglass shape, on an opaque horizontal disk of cold gas and dust that fit within a single pixel,” they added.

“More farther above and below the flat disc with thinned dust, bright light from the stars passes through the gas and dust, forming a large, translucent orange cone.”

“It’s equally important to notice where the starlight is blocked. Look for a very dark, wide V-shaped shape that is offset by the orange cone 90 degrees.”

“These areas may appear to be free of material, but in reality, they are the most dense surrounding dust, and small starlights will penetrate it.”

This new image was captured by Webb’s Near-Infrared Camera (Nircam) Equipment.

“The L483 is too large to fit in a single Webb snapshot. This image was taken to capture the top and the leak perfectly, so the bottom section is only partially visible,” the astronomer said.

“All symmetry and asymmetry in these clouds could ultimately be explained by updating the model and producing the same effect as researchers reconstruct the history of star emissions.”

“Astronomers also calculate how much material the stars expelled, which molecules were created when the materials were destroyed together, and how dense each region is.”

“Millions of years from now, when the stars form, they may each be about our solar mass.”

“They’ve cleared that area. They wipe out these translucent discharges.”

“All that remains is a small disc of gas and dust that the planet could eventually form.”

Source: www.sci.news

Webb detects ethereal Herbig Halo objects in the Taurus Molecular Cloud.

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Using Near-infrared camera (nircam) Mid-infrared instrument (Mil)Advanced on a James Webbspace Telescope, astronomers took a stunning image of an edge-on-protoplanetary disc around a Herbig Halo object HH 30The Dark Cloud LDN 1551, is located in Taurus Molecular Cloud.

This Webb/nircam/miri shows the Herbig-Haro object HH ​​30. et al.

The Herbig-Haro object is a small bright patch of nebula associated with protostars in the star-forming region.

These structures were first observed in the 19th century by American astronomer Sherburn Wesley Burnham, but were not recognized as a distinct type of ejection nebula until the 1940s.

The first astronomers to study them in detail were George Harbigue and Guillermo Halo, and they were later named.

Herbig Halo objects are formed in very specific circumstances. Hot gas discharged by the newborn star collides with the gas, hitting it at a speed of up to 250,000 kmh (155,000 mph), creating a bright shock wave.

They come in a wide range of shapes. The basic configuration is usually the same. Twin jets of hot gases are ejected in the opposite direction from the forming stars and flow through interstellar space.

“HH 30 is an example of where this effluent gas takes the form of a narrow jet,” the astronomer said.

“The source star is on one end of the jet and is hidden behind an edge-on-protoplanetary disc illuminated by the star.”

Using Webb Instruments, researchers investigate HH 30 objects in great detail.

They also analyzed data from the NASA/ESA Hubble Space Telescope and Atacama's Large Millimeter/Sub-Millimeter Array (ALMA).

“Long-wavelength data from Alma tracks the location of millimeter-sized dust particles in a narrow area on the middle surface of the disk,” they said.

“Short wavelength infrared data from Webb reveals the distribution of smaller dust grains.”

“These grains are one millionth of a meter in diameter. They are the size of a single bacteria.”

“Large dust grains are concentrated in the most dense portions of the disc, while small grains are much more widely used.”

“Combined with Alma's sharp radio-wavelength eyes, Webb's observations show that large dust particles must migrate within the disk and precipitate into a thin layer,” they added.

“Creating narrow, dense layers of dust is an important step in the formation of the planet.”

“In this densely populated area, dust grains together form pebbles, and ultimately form the planet itself.”

“In addition to the behavior of dust grains, images of Webb, Hubble and Alma reveal several different structures nested with each other.”

“A high-speed jet of gas appears at a 90-degree angle from the narrow central disc.”

“The narrow jet is surrounded by wider, cone-shaped spills.”

“Enclosing the cone runoff is a broad nebula that reflects the light from the young stars embedded in the disc.”

“Together, these data reveal that HH 30 is a dynamic location, where small dust grains and huge jets play a role in the formation of a new planet.”

Survey results It will be published in Astrophysical Journal.

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Ryozaki et al. 2025. JWST imaging of edge-on protranetary discs. IV. HH 30 disc mid-infrared dust scattering. APJin press; Arxiv: 2412.07523

Source: www.sci.news

A carbon-rich dust shell near Wolf Raye 140 has been found by Webb

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Wolf Rayet 140 (also known as WR 140 or HD 193793) is a system of two massive stars located approximately 5,000 light-years away in the constellation Cygnus. As these stars swing against each other, the stellar winds from each collide, compressing material and forming carbon-rich dust. New observations from the NASA/ESA/CSA James Webb Space Telescope show that 17 dust shells glowing in the mid-infrared are expanding into the surrounding space at regular intervals.

This image of the carbon-rich Wolf-Rayet star WR 140 was taken by the Webb Mid-Infrared Observer (MIRI) in September 2023. Image credits: NASA / ESA / CSA / STScI / E. Lieb, University of Denver / R. Lau, NSF's NOIRLab / J. Hoffman, University of Denver.

“Webb confirmed that Wolf-Rayet 140's dust shell is real,” said Emma Reeve, a doctoral student at the university. “We have shown that there is a visible change in an incredibly short period of time.” Originally from Denver, Colorado.

“All of the shells are moving away from the star at more than 2,600 kilometers per second, which is almost 1% of the speed of light.”

“We're used to thinking of events in the universe as happening slowly over millions or billions of years,” said Jennifer Hoffman, a professor at the University of Denver.

“In this system, the observatory shows that the dust shell is expanding year by year.”

Dr Olivia Jones, an astronomer at the UK Astronomical Technology Center, said: “It's truly amazing to see the real-time movement of these shells during the Webb observations, which were made just 13 months apart.” Ta.

“These new results provide the first glimpse of the potential role of such giant binary stars as dust factories in the universe.”

Like clockwork, the star's winds generate dust for a few months every eight years. The pair approaches each other in a wide and long orbit.

The web also shows where dust stops forming. Look for the dark area in the top left of the image.

The telescope's mid-infrared images detected shells that have survived for more than 130 years. The old shells have dissipated enough that they are now too dark to detect.

Astronomers estimate that a star will eventually produce tens of thousands of dust shells over hundreds of thousands of years.

“The dust in this system is quite cold, so mid-infrared observations are absolutely critical to this analysis,” said Dr. Ryan Lau, an astronomer at the NSF NOIRLab.

“Near-infrared and visible-light observations only show the shells closest to the star.”

“With these amazing new details…
findings Published in Astrophysics Journal Letter.

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Emma P. Reeve others. 2025. Dynamic signature of dust formation due to wind impact from WR 140. APJL 979, L3; doi: 10.3847/2041-8213/ad9aa9

Source: www.sci.news

Webb detects a gravitationally stretched star located 6.5 billion light years from Earth

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Using observations from the James Webb Space Telescope, astronomers found that at a time when the Universe was half its current age, a single galaxy behind the galaxy cluster Abel 370 had a redshift of 0.725 (Dragon We identified a star with more than 40 microlenses in an arc (called an arc).

In this Hubble image of Abell 370, the host galaxy in which 44 stars were discovered appears several times. Image credit: NASA.

“This groundbreaking discovery demonstrates for the first time that it is possible to study large numbers of individual stars in distant galaxies,” said Fengwu Sun, a postdoctoral researcher at the Harvard University & Smithsonian Center for Astrophysics. the doctor said.

“Previous studies using the NASA/ESA Hubble Space Telescope discovered about seven stars, and now we have the ability to resolve them in a way that was previously impossible. ”

“Importantly, observing larger numbers of individual stars will also help us better understand the dark matter in the lens surfaces of these galaxies and stars. i didn't understand.”

In the study, Sun and his colleagues analyzed web images of a galaxy known as Dragon Arc, which lies along the line of sight from Earth behind a massive galaxy cluster called Abel 370.

Through gravitational lensing, Abel 370 stretches the Dragon Arc's characteristic spiral into an elongated shape. It is a hall of mirrors as big as the universe.

Astronomers carefully analyzed the color of each star in the Dragon Arc and discovered that many of them were red supergiants. This is in contrast to previous discoveries that primarily identified blue supergiants.

The researchers say this difference in star types highlights the unique ability of Webb observations at infrared wavelengths to reveal stars even at low temperatures.

“When we discovered these individual stars, we were actually looking for background galaxies that were magnified by galaxies within this giant cluster,” Dr. Sun said.

“But when we processed the data, we found that there were many what appeared to be individual star points.”

“It was an exciting discovery because it was the first time we had been able to see so many individual stars so far away.”

“We know more about red supergiants in our local galactic neighborhood, because they are closer and we can take better images and spectra, and sometimes even break up stars. It’s from.”

“Knowledge gained from studying red supergiants in the local universe can be used in future studies to interpret what happens next to red supergiants during the early stages of galaxy formation.”

Most galaxies, including the Milky Way, contain tens of billions of stars. In nearby galaxies, such as the Andromeda galaxy, astronomers can observe stars one by one.

But in galaxies that are billions of light years away, their light has to travel billions of light years to reach us, so stars appear mixed together, which explains how galaxies form and evolve. This has been a long-standing challenge for scientists who study it.

“To us, very distant galaxies usually look like diffuse, blurry clumps,” says Dr. Yoshinobu Fudamoto, an astronomer at Chiba University.

“But in reality, those clumps are made up of so many individual stars that our telescopes can't resolve them.”

of findings Published in a magazine natural astronomy.

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Yuya Fudamoto others. Identified over 40 gravitationally expanded stars in the galaxy at redshift 0.725. Nat Astronpublished online on January 6, 2025. doi: 10.1038/s41550-024-02432-3

Source: www.sci.news

Webb finds evidence of active formation of low-mass galaxies in the early universe

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The newly discovered galaxy, called the Firefly Radiance, existed about 600 million years after the Big Bang and consisted of at least 10 star clusters.

The Firefly Sparkle galaxy is in the process of gathering and forming new stars, exists about 600 million years after the Big Bang, and would weigh about the same as the Milky Way if we could turn back the clock and watch the galaxy develop . Image credits: NASA / ESA / CSA / STScI / C. Willott, NRC-Canada / L. Mowla, Wellesley College / K. Iyer, Columbia.

The most distant galaxies detected date from when the universe was about 5% of its current age.

However, the mass of these galaxies is about 10,000 times smaller than that of the Milky Way, making them difficult to observe.

The Firefly Sparkle galaxy was first observed by the NASA/ESA Hubble Space Telescope, but detailed new observations by the NASA/ESA/CSA James Webb Space Telescope shed more light on its formation.

“We never thought it would be possible to resolve galaxies that existed so early in the universe into so many different components, much less that their mass would be comparable to the mass of our galaxy in the process of forming. “I never thought it would be possible to discover similarities between the two,” he said. Dr. Ramiya Moura, astronomer at Wellesley College.

“There’s so much going on inside this small galaxy, including various stages of star formation.”

Webb was able to image the Firefly Sparkle galaxy in sufficient detail for two reasons.

One is the blessings of the universe. A massive galaxy cluster in the foreground, called MACS J1423.8+2404, radically enhanced the appearance of distant galaxies through a natural effect known as gravitational lensing.

And when combined with the telescope’s specialization in high-resolution imaging in infrared light, Webb provided unprecedented new data on the contents of galaxies.

“Without the benefit of this gravitational lensing, we would not have been able to understand this galaxy,” said Columbia University astronomer Karltej Ayer.

“We knew that was expected based on current physics, but to actually witness it was surprising.”

Astronomers also observed two neighboring galaxies they named Firefly Best Friend and Firefly New Best Friend. These galaxies are located 6,000 and 40,000 light-years from Firefly Sparkle, respectively, and are smaller than the present-day Milky Way.

The authors propose that the firefly glow could be a young, gas-rich galaxy in the early stages of formation.

These show that Firefly Sparkle’s mass is concentrated in 10 star clusters, with a total mass about 10 million times the mass of the Sun.

As such, Firefly Sparkle is one of the lowest-mass galaxies to have resolved into star clusters observed at the dawn of the universe, when galaxies began to form, and its mass is similar to that of the progenitor Milky Way. is.

“It has long been predicted that galaxies in the early universe formed through continuous interactions and mergers with other smaller galaxies,” says Yoshihisa Asada, a doctoral student at Kyoto University.

“We may be witnessing this process in action.”

“We have just started using space microscopy, so this is only the first of many such galaxies that Webb will discover,” said Dr. Marcia Bradač, an astronomer at the University of Ljubljana.

“Just as we can see pollen grains on plants with a microscope, the incredible resolution of the Webb and the magnifying power of gravitational lenses allows us to see tiny pieces inside galaxies.”

“Our team is currently analyzing all the early galaxies, and the results all point in the same direction. We still don’t know much about how these early galaxies formed. .”

of study Published in a magazine nature.

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L. Mora others. 2024. Low-mass galaxies were formed from star clusters in the Universe 600 million years ago. nature 636, 332-336; doi: 10.1038/s41586-024-08293-0

Source: www.sci.news

Webb confirms Hubble’s calculations of distance

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New observations by NASA/ESA/CSA’s James Webb Space Telescope confirm previous measurements by the NASA/ESA Hubble Space Telescope of the distances between nearby stars and galaxies, and confirm measurements of the universe’s mysterious expansion. Provide critical cross-checking to address discrepancies. This contradiction, known as the Hubble tension, remains unexplained by even the best cosmological models.

This artist’s impression shows the evolution of the universe, starting with the Big Bang on the left and continuing with the emergence of the Cosmic Microwave Background. The formation of the first stars ends the Dark Ages of the universe, followed by the formation of galaxies. Image credit: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

“The discrepancy between the observed rate of expansion of the universe and the predictions of the Standard Model suggests that our understanding of the universe may be incomplete,” said Nobel laureate and Johns Hopkins University professor Adam Riess. “There is,” he said.

“Now that NASA’s two flagship telescopes are confirming each other’s discoveries, we must take this issue very seriously. It’s a challenge, but it’s a It’s also a great opportunity to learn more.”

The new research builds on Professor Rees’ Nobel Prize-winning discovery that the expansion of the universe is being accelerated by a mysterious dark energy that permeates the vast expanses of space between stars and galaxies.

The authors used the largest sample of Webb data collected during the first two years of the universe to test the Hubble telescope’s measure of the rate of expansion of the universe, a number known as the Hubble constant.

They used three different methods to measure the distance to the galaxy where the supernova occurred, using a method previously measured by the Hubble telescope and known to provide the most accurate “local” measurement of this number. We focused on the distance that is being

Observations from both telescopes were in close agreement, revealing that Hubble’s measurements were accurate and eliminating inaccuracies large enough to attribute the tension to Hubble’s errors.

Still, the Hubble constant remains a mystery. This is because measurements based on current telescopic observations of the universe produce higher values ​​compared to projections made using the standard model of cosmology. The Standard Model is a widely accepted framework for how the universe works, calibrated with cosmic microwave background data. Weak radiation left over from the Big Bang.

The Standard Model Hubble constant is approximately 67-68 km/sec per megaparsec, but measurements based on telescope observations typically yield higher values ​​of 70-76, with an average of 73 km/sec/megaparsec.

This discrepancy has puzzled cosmologists for more than a decade. A difference of 5 to 6 kilometers per second per megaparsec is too large to be explained solely by deficiencies in measurement and observation technology.

Webb’s new data eliminates significant bias in Hubble’s measurements, so the Hubble tension could be due to unknown factors or gaps in cosmologists’ understanding of physics that have yet to be discovered.

“Webb’s data represent the first high-definition view of the universe, greatly improving the signal-to-noise ratio of the measurements,” said Xiang Li, a graduate student at Johns Hopkins University. .

This image, taken with the Nicholas U. Mayall 4-meter telescope, shows the spiral galaxy Messier 106. Two dwarf galaxies (NGC 4248 in the lower right and UGC 7356 in the lower left) also appear in the image. Image credits: KPNO / NOIRLab / NSF / AURA / New Mexico State University MT Patterson / University of Alaska Anchorage TA Chancellor / M. Zamani & D. de Martin.

The astronomers used the known distance to the spiral galaxy Messier 106 (also known as M106 or NGC 4258) as a reference point to cover roughly one-third of Hubble’s total galaxy sample.

Despite the small dataset, they achieved impressive accuracy, showing less than 2% difference between measurements. This is much smaller than the approximately 8-9% size of the Hubble tension mismatch.

In addition to analyzing pulsating stars called Cepheid variable stars, the gold standard for measuring distances in the universe, they cross-checked measurements based on the brightest red giant stars in the same galaxy as carbon-rich stars. .

All galaxies observed by Webb with supernovae yielded a Hubble constant of 72.6 km per second per megaparsec. This is about the same as the 72.8 km per second per megaparsec that Hubble found for the very same galaxy.

“One possible explanation for the Hubble tension is that something was missing in our understanding of the early universe, such as a new component of matter that unexpectedly bombarded the universe after the Big Bang, nascent dark energy. I guess so,” Johns said. Mark Kamionkowski, a cosmologist at Hopkins University, was not involved in the study.

“And there are other ideas that might do the trick, like interesting dark matter properties, exotic particles, changing electron masses, or primordial magnetic fields. Theorists have a right to be pretty creative. It is.”

of result Published in astrophysical journal.

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Adam G. Reese others. 2024. JWST validates HST distance measurements: Supernova subsample selection explains differences in JWST estimates of local H0. APJ 977, 120; doi: 10.3847/1538-4357/ad8c21

Source: www.sci.news

Webb finds 138 main belt asteroids measuring 10 meters in diameter

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These asteroids are as small as 10 meters in diameter, making them the smallest asteroids ever observed in the major asteroid belt.

Artist Webb's illustration reveals clusters of main-belt decameter asteroids in infrared light. Image credit: Ella Mall/Julian de Wit.

The discovery of asteroids is essential to planetary defense efforts aimed at preventing collisions with Earth, such as the frequent megaton explosions caused by decameter impactors.

Large asteroids (=>100 km) remain in the main belt since their formation, while smaller asteroids are typically transported into the near-Earth object (NEO) population.

“We were able to detect NEOs very close to Earth, up to 10 meters in size,” said MIT researcher Dr. Artem Brudanov.

“We now have a way to discover these small asteroids when they are far away, so we can do more precise trajectory tracking, which is important for planetary defense.”

For this study, astronomers used data from the NASA/ESA/CSA James Webb Space Telescope to search for small asteroids.

Coincidentally, asteroids orbiting the main asteroid belt are much brighter in infrared wavelengths than in visible wavelengths, making them much easier to detect with Webb's infrared capabilities.

Researchers were able to discover eight known asteroids in the main asteroid belt.

Further investigation subsequently discovered 138 new asteroids around the belt, all within a few tens of meters in diameter, making them the smallest main-belt asteroids ever detected. .

They think several asteroids may be on their way to becoming NEOs, and one of them is probably the Trojans, or Jupiter-tracking asteroids.

“We thought we would only detect a few new objects, but we detected far more objects than we expected, especially small ones,” said Professor Julian de Witt of the Massachusetts Institute of Technology.

“This is an indication that we are exploring a new population regime, where many more small objects are formed by a chain of collisions that very efficiently disintegrates asteroids smaller than about 100 meters. It will be done.”

“This is a completely new and unexplored territory that we are entering, thanks to modern technology,” said Dr. Brudanov.

“This is a great example of what we can do as a field when we look at data from a different perspective. Sometimes the benefits can be huge, and this is one of them.”

“The statistics of these very small main-belt asteroids are very important for modeling asteroid populations,” said Dr. Miroslav Broz, a researcher at Charles University in Prague.

In fact, these are debris ejected during the impact of larger, kilometer-sized asteroids, which are observable and often exhibit similar orbits around the sun, placing them in a “family” of asteroids. Can be grouped. ”

“We never expected that we could use state-of-the-art exoplanet observations to achieve such impactful solar system bonus science,” said Dr. Michael Guillon, a researcher at the University of Liège.

ESA researcher Dr Marco Micheli said: “Thanks to the web, we can now discover these small asteroids even when they are located far from Earth, allowing us to make more accurate orbit determinations. “This is extremely important for planetary defense.” Near Earth Object Coordination Center.

of the team paper Published in today's magazine nature.

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AY Brudanov others. JWST sighting of a 10-meter main belt asteroid and views on the meteorite source. naturepublished online on December 9, 2024. doi: 10.1038/s41586-024-08480-z

Source: www.sci.news

Webb Reveals a Fresh Perspective on the Sombrero Galaxy

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sharp resolution Web’s mid-infrared device (MIRI) focuses on details of the outer ring of the Sombrero Galaxy, providing insight into how dust is distributed.

This web image shows the Sombrero Galaxy. Image credit: NASA/ESA/CSA/STScI.

The Sombrero Galaxy is located approximately 28 million light-years away in the constellation Virgo.

This spiral galaxy, also known as Messier 104, M104, or NGC 4594, was discovered by French astronomer Pierre Méchain on May 11, 1781.

It is about 49,000 light-years in diameter, about one-third the size of our Milky Way galaxy.

The Sombrero galaxy has a very large central bulge and a supermassive black hole.

We are looking directly at the galaxy, at an angle of 6 degrees south of its face. Its dark dusty path dominates the view.

“The clumpy nature of the dust, in which MIRI detects carbon-containing molecules called polycyclic aromatic hydrocarbons, may indicate the presence of young star-forming regions,” Webb astronomers said in a statement.

“But unlike some of the galaxies studied with Webb, such as Messier 82, which has 10 times as many stars as the Milky Way, the Sombrero galaxy is not a special hotbed of star formation.”

“The Sombrero ring produces less than 1 solar mass per year of stars, compared to about 2 solar masses per year for the Milky Way.”

“The supermassive black hole at the center of the Sombrero galaxy, also known as an active galactic nucleus (AGN), is fairly docile, even at a massive 9 billion solar masses,” the researchers noted.

“Classified as a low-luminosity AGN, it slowly chews up material falling from the galaxy while emitting bright and relatively small jets.”

“Also, there are about 2,000 globular clusters within the Sombrero galaxy, which are collections of hundreds of thousands of old stars held together by gravity,” the researchers said.

“This type of system acts as a pseudo-laboratory for astronomers to study stars. There are thousands of stars in one system of the same age but with different masses and other properties, making it difficult to compare It’s an interesting opportunity for research.”

“In the MIRI images, galaxies of different shapes and colors are scattered across the cosmic background.”

“The different colors of these background galaxies can tell astronomers about their properties, such as their distance.”

Source: www.sci.news

Hubble and Webb telescopes examine the planetary debris disk surrounding Vega

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There is no clear evidence that one or more large exoplanets are punching through the frontal debris disk surrounding Vega, one of the brightest stars in the night sky.

Webb used the Mid-Infrared Instrument (MIRI) to obtain images of the circumstellar disk around Vega. Image credits: NASA / ESA / CSA / STScI / S. Wolff, University of Arizona / K. Su, University of Arizona / A. Gáspár, University of Arizona.

Vega is a young, massive star located about 25 light-years away in the constellation Lyra.

This star is classified as type A. This is the name of stars that tend to be larger, younger, and rotate much faster than the Sun.

Vega, also known as Alpharilla, Gliese 721, and HD 172167, is 455 million years old and has a mass equal to two solar masses.

It rotates around its axis every 16 hours. This is much faster than the Sun, which has a rotation period measured in 27 Earth days.

Vega is legendary because it provided the first evidence of matter orbiting a star.

this was the first made a hypothesis However, it took more than 200 years before the first observational evidence was collected in 1984.

A mysterious excess of infrared radiation from warm dust has been detected by NASA's Infrared Astronomy Satellite (IRAS). It was interpreted to be a shell or disk of dust extending from the star to twice Pluto's orbital radius.

In the new study, astronomers analyzed images of Vega's debris disk taken by the NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webb Space Telescope.

“Vega was one of the first typical planetary debris disks to be discovered,” Dr. Kate Hsu of the University of Arizona and colleagues said in their paper. paper Introducing the results of a web survey.

“This opens up a wide field of research, which is now being used to identify relatively low-mass exoplanets that are unreachable with other discovery techniques, as well as to reveal detailed properties of small bodies in other planetary systems. It is used in

“Vega continues to be an anomaly,” added Dr. Schuyler Wolf, an astronomer at the University of Arizona and lead author of the paper. paper Introducing Hubble's discoveries.

“The structure of the Vega system is markedly different from our solar system, where giant planets like Jupiter and Saturn prevent dust from dispersing like Vega.”

“For comparison, there is a nearby star called Fomalhaut, which is about the same distance, age, and temperature as Vega.”

“However, Fomalhaut's circumstellar structure is very different from Vega's. Fomalhaut has three nested debris belts.”

“Exoplanets have been suggested to be bodies that guide the dust around Fomalhaut, which gravitationally compresses it into a ring, but no planets have yet been positively identified.”

“Given the physical similarities between Vega and Fomalhaut's stars, why does Fomalhat appear to be able to form planets, but Vega not?” George Rieke, also of the University of Arizona The doctor said:

“What's the difference? Did the circumstellar environment, or the star itself, make the difference? What's puzzling is that the same physics is at work in both,” Wolff added.

Hubble used the Space Telescope Imaging Spectrograph (STIS) to obtain this image of the circumstellar disk around Vega. Image credits: NASA / ESA / CSA / STScI / S. Wolff, University of Arizona / K. Su, University of Arizona / A. Gáspár, University of Arizona.

Webb observed the infrared glow from a disk of sand-sized particles swirling around a scorching blue-white star that is 40 times brighter than the Sun.

Hubble captures the disk's outer halo, which contains smoke-sized particles that reflect starlight.

The distribution of dust within Vega's debris disk is layered. This is because the pressure of the star's light pushes smaller particles out faster than larger ones.

“Between the Hubble and Webb telescopes, we get a very clear view of Vega,” said Dr. András Gaspard, an astronomer at the University of Arizona and co-author of both papers.

“This is a mysterious system because it is unlike any other circumstellar disk we have observed.”

“Vega discs are smooth. Incredibly smooth.”

The Vega disk has a subtle gap about 60 AU (astronomical units) from the star (twice the distance of Neptune from the Sun), but otherwise it is very smooth the entire time until it disappears into the star's glare. is.

This indicates that there are no planets, at least up to the mass of Neptune, orbiting large orbits like our solar system.

“We are looking in detail at how much diversity there is in the circumstellar disk and how that diversity is tied to the underlying planetary system,” Dr. Hsu said.

“Even if we can't see what the hidden planets are, we’re still discovering a lot about planetary systems.”

“There are still many unknowns about the process of planet formation, but we think these new observations from Vega will help constrain models of planet formation.”

The two papers are astrophysical journal.

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Kate Y.L. Sue others. 2024. Imaging the Vega debris system using JWST/MIRI. APJin press. arXiv: 2410.23636

Skylar G. Wolf others. 2024. Hubble Space Telescope probes deep into the scattered light dust ring around Vega. APJin press. arXiv: 2410.24042

Source: www.sci.news

Webb makes a groundbreaking discovery of a region on a centaur with active outgassing

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Centaur is a former trans-Neptunian object that has been moved within Neptune's orbit by the planet's subtle gravitational influence over the past several million years, and could eventually become a short-period comet.

29P/An artist's concept showing the gas release activity of Schwassmann-Wachmann 1 from the side. Image credit: NASA/ESA/CSA/L. Hustak, STScI.

Centaurs are transitional objects between primitive transsolar system objects and Jupiter-based comets.

Their composition and activity provide fundamental clues about the processes that influence the evolution of and interactions between these small celestial bodies.

“Centaurs are likely part of the remnants of the formation of our planetary system,” said Dr. Sarah Fudge, a researcher at NASA's Goddard Space Flight Center and American University.

“Because they are stored at very low temperatures, they preserve information about the volatiles of the solar system's early stages.”

“The web really opened the door for us to impressive resolution and sensitivity. When we saw the data for the first time, we were excited. We had never seen anything like this before. I've never had one before.”

use Webb's NIRSpec (near infrared spectrometer) deviceDr. Fudge and colleagues observed 29P/Schwasmann Wachmann 1 (29P for short) is a centaur. known This is because very active, quasi-periodic explosions occur.

29P changes in intensity every six to eight weeks, making it one of the most active objects in the outer solar system.

They discovered a new jet of carbon monoxide and a jet of carbon dioxide gas never before seen, giving new clues about the nature of the centaur's core.

No signs of water vapor were detected in 29P's “atmosphere,” but this may be related to the extremely cold temperatures present on this object.

Based on the data collected by Webb, the researchers created a 3D model of the jet to understand its direction and origin.

Through modeling efforts, they discovered that the jets were emitted from different regions of the centaur's core, even though the nucleus itself could not be resolved by the web.

The angle of the jet suggests that the core may be a collection of separate objects with different compositions. However, other scenarios cannot be ruled out yet.

fudge others. collected data for 29P/Schwassmann-Wachmann 1 using Webb's spectrophotographic capabilities. Image credit: NASA/ESA/CSA/L. Hustak, STScI/S. Faggi, NASA's Goddard Space Flight Center and American University.

Dr. Jeronimo Villanueva, a researcher at NASA Goddard Space Flight Center, said: “The fact that there are such dramatic differences in the abundance of carbon monoxide and carbon dioxide across the surface of 29P means that 29P is This suggests that it may be possible.”

“The two parts probably merged to form this centaur, which is a mixture of very different objects that went through separate formation paths.”

“This challenges our ideas about how primitive objects are created and stored in the Kuiper belt.”

The reasons for 29P's brightness outburst and the mechanisms behind its outgassing activity through carbon monoxide and carbon dioxide jets remain two major areas of interest that continue to require further investigation.

In the case of comets, scientists know that their jets are often driven by the release of water gas.

However, Centaur's location means that the nature of its outgassing activity is different from that of comets, as it is too cold for water ice to sublimate.

“We only had time to look at this object once, and it was like a snapshot in time,” said Dr. Adam McKay, a researcher at Appalachian State University.

“I would like to go back and look at 29P over a longer period of time. Is the jet always pointing in that direction? Perhaps there is another carbon monoxide jet that turns on at a different point in the rotation cycle? Is there one?”

“Looking at these jets over time will give us better insight into what is causing these explosions.”

of the team paper Published in a magazine nature.

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S.Fudge others. Inhomogeneous outgassing regions were identified in active centaur 29P/Schwassmann-Wachmann 1. Nat Astronpublished online on July 8, 2024. doi: 10.1038/s41550-024-02319-3

This article is a version of a press release provided by NASA.

Source: www.sci.news

Webb discovers carbon dioxide and hydrogen peroxide found on Charon’s surface

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Using data from near infrared spectrometer (NIRSpec) Astronomers aboard the NASA/ESA/CSA James Webb Space Telescope have detected carbon dioxide (CO2) and hydrogen peroxide (H2O2) The frozen surface of Pluto’s moon Charon. Their findings provide new insights into Charon’s chemical processes and surface composition, and could help understand the origin and evolution of icy objects in the outer solar system.

Protopapa others. Using Webb telescope observations (white), we detected spectral signatures of carbon dioxide and hydrogen peroxide on Charon. This extends the wavelength range of previous New Horizons flyby measurements (pink). Image credit: S. Protopapa / SwRI / NASA / ESA / CSA / STScI / JHUAPL.

Beyond Neptune, there is a collection of fascinating small objects known as trans-solar objects (TNOs) that orbit around the Sun.

These objects act as time capsules, giving planetary scientists a glimpse of the early solar system.

“Charon is unique in that it is the only medium-sized TNO for which geological maps are available, 500 km to 1700 km in diameter, thanks to measurements returned by NASA’s New Horizons mission,” said Sylvia of the Southwest Research Institute. Dr. Protopapa said. And her colleagues.

“Unlike larger TNOs (such as Pluto, Eris, and Makemake), Charon’s surface is not covered by supervolatile ices such as methane, with possible exceptions toward the poles.”

“As a result, Charon serves as an excellent candidate to gain valuable insights into processes such as differentiation, radiation exposure, and cratering within the Kuiper belt.”

“Although Charon has been extensively studied since its discovery in 1978, previous spectral data were limited to wavelengths below 2.5 μm, leaving gaps in our understanding of its surface composition. “

“The presence of water ice, ammonia-containing species, and organic compounds had been previously noted, but the spectral range used was insufficient to detect other compounds.”

Protopapa and his co-authors used Webb’s near-infrared spectrometer to observe Charon at wavelengths between 1.0 and 5.2 μm.

They conducted four observations at different longitudes, and together with laboratory experiments and spectral modeling, they confirmed the presence of crystalline water ice and ammonia, and also identified carbon dioxide and hydrogen peroxide.

“Thanks to Webb’s advanced observational capabilities, our team is able to explore the light scattered from Charon’s surface at longer wavelengths than previously possible, allowing us to explore the complexities of this fascinating object. “We were able to further deepen our understanding of human health,” said Dr. Ian Wong, a scientist at the institute. Space Telescope Science Institute.

The presence of hydrogen peroxide suggests active processing of water ice by irradiation and light at Charon’s surface, while carbon dioxide is present since its formation and is due to subsurface carbon dioxide exposed to the surface by impact events. It is thought to originate from carbon reservoirs.

The detection of carbon dioxide and hydrogen peroxide on Charon represents a step forward in planetary science and provides insight into the moon’s surface chemistry.

This study could lay the foundation for future studies to investigate the dynamics of extrasolar objects, their surface compositions, and the effects of solar radiation.

“Our preferred interpretation is that the upper layer of carbon dioxide originated from within and was exposed to the surface through cratering events,” Dr Protopapa said.

“Carbon dioxide is known to exist in the region of the protoplanetary disk where the Pluto system formed.”

“New insights are made possible by the synergy of Webb observations, spectral modeling, and laboratory experiments, and may be applicable to similar medium-sized objects beyond Neptune.”

of result Posted in today’s diary nature communications.

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S. Protopapa others. 2024. Detection of carbon dioxide and hydrogen peroxide on Charon’s layered surface using JWST. Nat Commune 15, 8247; doi: 10.1038/s41467-024-51826-4

Source: www.sci.news

Webb finds mysterious cosmic question mark in distorted galaxy formation

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Seven billion years ago, the universe’s star formation boom began to slow. What did our Milky Way galaxy look like at that time? Astronomers using the NASA/ESA/CSA James Webb Space Telescope have discovered a clue in the form of a cosmic question mark, the result of an unusual alignment in space spanning several light-years.

Galaxy cluster MACS-J0417.5-1154 is so massive that it warps the fabric of space-time and distorts the appearance of galaxies behind it. This phenomenon is known as gravitational lensing. This natural phenomenon magnifies distant galaxies, sometimes causing them to appear multiple times in the image, as Webb saw here. Two distant interacting galaxies (a spiral galaxy seen face-on and a dusty red galaxy seen edge-on) appear multiple times, tracing a familiar shape across the sky. Active star formation and the remarkably perfect spiral shape of the galaxy seen face-on indicate that these galaxies are just beginning to interact. Image credit: NASA/ESA/CSA/STScI/V. Estrada-Carpenter, Saint Mary’s University.

“There are only three or four known examples of similar gravitational lensing configurations in the observable universe, so this discovery is exciting as it demonstrates the power of Webb and suggests that we may find more like it in the future,” said Dr Guillaume Despres, from St Mary’s University.

The region has previously been observed by the NASA/ESA Hubble Space Telescope, but Webb was the first to spot the dusty red galaxy forming an intriguing question mark shape.

This is because the wavelengths of light that Hubble detects are trapped in space dust, while longer wavelengths of infrared light pass through Webb’s instruments and can be detected.

Astronomers used both telescopes to observe the galaxy cluster. MACS-J0417.5-1154The cluster is so large that it distorts the fabric of space-time, acting like a magnifying glass.

This will allow astronomers to see clearer details of the much more distant galaxies behind the cluster.

But the same gravitational effects that expand galaxies also cause distortions, which can result in galaxies appearing spread out in an arc across the sky, or appearing multiple times.

This optical illusion in space is called gravitational lensing.

The red galaxy Webb uncovered, along with the spiral galaxy it interacts with, previously detected by Hubble, is magnified and distorted in an unusual way that requires a special and rare alignment between the distant galaxy, the lens, and the observer — something astronomers call hyperbolic umbilical gravitational lensing.

This explains five images of the galaxy pair seen in the Webb image, four of which trace the top of the question mark.

The question mark points are, from our perspective, unrelated galaxies that happen to be in the right place and spacetime.

In addition to developing a case study for Webb, Niris Noting the ability of their infrared imaging device and slitless spectrometer to detect star formation locations in galaxies billions of light years away, the research team also couldn’t help but notice the shape of the question mark.

“This is really cool. I got interested in astronomy when I was younger because I saw amazing images like this,” said Dr Marcin Sawicki, also from Saint Mary’s University.

“Knowing when, where and how star formation occurs in galaxies is crucial to understanding how galaxies have evolved throughout the history of the universe,” said Dr Vicente Estrada Carpenter from Saint Mary’s University.

“The results show that star formation is widespread in both. The spectral data also confirm that the newly discovered dusty galaxy is located at the same distance as the frontal spiral galaxy, suggesting that the two are probably starting to interact.”

“Both galaxies in the question mark pair show several dense regions of active star formation, likely the result of the gas in the two galaxies colliding.”

“But neither galaxy seems particularly disturbed, so perhaps we are seeing the beginning of an interaction.”

“These galaxies, seen billions of years ago when star formation was at its peak, are similar in mass to the Milky Way at that time,” Dr Sawicki said.

“Thanks to Webb, we can now study what our galaxy was like in its teenage years.”

Team paper Published in Monthly Bulletin of the Royal Astronomical Society.

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Vicente Estrada Carpenter others2024. CANUCS JWST/NIRISS We will use grism spectroscopy to investigate when, where and how star formation occurs in a pair of galaxies at cosmic noon. MNRAS 532 (1): 577-591; doi: 10.1093/mnras/stae1368

This article is based on a press release provided by NASA.

Source: www.sci.news

Webb finds six free-floating exoplanets in NGC 1333

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How to use Near-infrared imaging device and slitless spectrometer Using the NIRISS instrument on the NASA/ESA/CSA James Webb Space Telescope, astronomers have discovered six new free-floating planet-mass members of NGC 1333, with estimated masses ranging from 5 to 15 times that of Jupiter. One of these objects is five times the mass of Jupiter (about 1,600 times that of Earth), making it likely the lowest-mass object with a dusty planetary orbiting disk.

NIRISS-NGC1333-5 (also known as NN5), with an estimated mass five times that of Jupiter, is the lowest-mass object yet found in NGC 1333 and is likely the lowest-mass object with a disk in any region identified so far. Image credit: Langeveld others., doi:10.3847/1538-3881/ad6f0c.

NGC 1333 is a star-forming cluster located about 1,000 light-years away in the northern constellation Perseus.

Also known as Ced 16 and LBN 741, the star cluster was first discovered in 1855 by German astronomer Eduard Schoenfeld.

NGC 1333 is only 1 to 3 million years old and harbors brown dwarfs equivalent to about half the number of stars, a higher proportion than previously observed.

“We're exploring the limits of the star formation process,” said astrophysicist Adam Langeveld of Johns Hopkins University.

“If we had a young Jupiter-like object, could it become a star under the right conditions? This is important context for understanding the formation of stars and planets.”

Dr. Langeveld and his colleagues used Webb's NIRISS instrument to carry out an extremely deep spectroscopic survey of NGC 1333.

Observations have discovered 19 known brown dwarfs and six free-floating planetary-mass objects with masses between 5 and 10 times that of Jupiter.

This means they are among the most lightweight objects yet discovered that were formed from processes that normally produce stars or brown dwarfs (objects that straddle the boundary between stars and planets, do not undergo hydrogen fusion reactions, and disappear over time).

“We used the Webb Telescope's unprecedented sensitivity at infrared wavelengths to search for the faintest members of young star clusters and answer a fundamental question in astronomy: how can objects form star-like shapes with light?” said Ray Jayawardene, an astrophysicist at Johns Hopkins University.

“The smallest stray objects forming like stars turn out to be comparable in mass to giant exoplanets orbiting nearby stars.”

Webb's observations, despite being sensitive enough to detect such objects, did not find any objects with a mass less than five times that of Jupiter.

This strongly suggests that stars less massive than this threshold are likely to form in the same way as planets.

“Our observations confirm that nature produces planetary-mass objects in at least two different ways: from the collapse of clouds of gas and dust as stars form, and from disks of gas and dust around young stars, such as Jupiter in our own solar system,” Dr Jayawardene said.

The most interesting of the planetary-mass objects is NIRISS-NGC1333-5, which is the lightest, with an estimated mass of five Jupiters.

“The presence of a dust disk means that the object almost certainly formed like a star, because cosmic dust typically revolves around a central object during the early stages of star formation,” Dr Langeveld said.

“Disks are also a prerequisite for planet formation, so our observations could also have important implications for potential small planets.”

“These small objects with masses comparable to the giant planets could potentially form planets themselves,” said Dr Alex Scholz, an astrophysicist at the University of St Andrews.

“This could be a nursery for small planetary systems, much smaller in scale than our solar system.”

Astronomers also discovered a new brown dwarf with a planetary-mass companion, a rare find that calls into question theories about how binary star systems form.

“Such pairs likely formed from a contracting, fragmenting cloud, much like a binary star system,” Dr Jayawardene said.

“The diversity of systems created by nature is astonishing and inspires us to refine our models of star and planet formation.”

of Survey results will be published in Astronomical Journal.

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Adam B. Langefeld others2024. JWST/NIRISS Deep Light Survey of Young Brown Dwarfs and Free-Floating Planets. AJin press; doi: 10.3847/1538-3881/ad6f0c

Source: www.sci.news

Webb discovers unseen elements of Messier 106

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NASA has released a stunning new image of the active center of nearby spiral galaxy Messier 106, taken with the NASA/ESA/CSA James Webb Space Telescope.

This Webb image shows Messier 106, a spiral galaxy 20 million light-years away in the constellation Canes Venatici. Image courtesy of NASA / ESA / CSA / Webb / J. Glenn.

Located more than 20 million light years from Earth in the small northern constellation Canes Venatici, Messier 106 is one of the brightest spiral galaxies and closest to our Milky Way Galaxy.

Also known as M106 or NGC 4258, the galaxy was discovered in 1781 by Charles Messier's observational assistant, Pierre Méchain.

“Despite its name, Messier 106 was neither discovered nor catalogued by the famous 18th century astronomer Charles Messier,” astronomers Webb said in a statement.

“This galaxy was discovered by his assistant Pierre Méchain, but was not catalogued during his lifetime.”

“Messier 106, along with six other objects they discovered but did not record, Messier Catalogue In the 20th century.”

Messier 106 is similar in size and brightness to our galactic neighbor, the Andromeda Galaxy.

Messier 106 measures more than 130,000 light-years from end to end, but because of its great distance from the Milky Way galaxy, it appears very small from Earth's perspective.

At the center of Messier 106 lies an extremely active supermassive black hole with a mass about 40 million times that of the Sun.

Unlike the black hole at the center of our Milky Way galaxy, which only occasionally sucks in gas particles, Messier 106's black hole is actively consuming material.

“As the gas spirals toward Messier 106's black hole, it heats up and emits powerful radiation,” the astronomers said.

New images of Messier 106 Webb's near infrared camera (NIRCam).

“The observations were made as part of a dedicated program to study active galactic nuclei – luminous central regions of galaxies dominated by light emitted by dust and gas falling into a black hole,” the researchers said.

“The blue areas in this image reflect the distribution of stars throughout the central region of the galaxy.”

“Orange areas indicate warmer dust, while more intense reds represent cooler dust.”

“The blue-green, green and yellow tones near the center of the image represent the various gas distributions across the region.”

Messier 106 also has a notable feature: it has two “unusual” extra arms that are visible in radio and x-ray wavelengths, rather than visible light.

“Unlike normal arms, these are made up of hot gas rather than stars,” the scientists said.

“Astronomers think these extra arms are the result of black hole activity, a feedback effect that has been seen in other galaxies.”

“These could be caused by outflows of material produced by the violent churning of gas around the black hole, creating a phenomenon similar to waves rushing out of the ocean when they hit rocks near the shore.”

Source: www.sci.news

Webb captures direct image of a temperate superjupiter orbiting Epsilon Indi A

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Astronomers Webb’s MIRI (Mid-Infrared Instrument) The image was taken of Epsilon Indi Ab, a gas giant several times the mass of Jupiter, located about 12 light years from Earth.

This image of Epsilon Indi Ab was taken with a coronagraph on Webb’s MIRI instrument. Image courtesy NASA / ESA / CSA / Webb / STScI / E. Matthews, Max Planck Institute for Astronomy.

Of the 25 planets that have been directly imaged to date, all are less than 500 million years old, and all but six are less than 100 million years old.

The newly imaged planet orbits Epsilon Indi A (HD 209100, HIP 108870), a K5V type star that is roughly the age of the Sun (3.7 to 5.7 billion years).

“Previous observations of this system have been more indirect measurements of the star, which gave us advance knowledge that there is likely to be a giant planet in the system tugging at the star,” said Dr Caroline Morley, an astronomer at the University of Texas at Austin.

“That’s why our team chose this system as our first observational system at Webb.”

“This discovery is fascinating because the planet is very similar to Jupiter – it’s a little warmer and more massive, but it’s more similar to Jupiter than any other planet imaged so far,” said Dr Elizabeth Matthews, astronomer at the Max Planck Institute for Astronomy.

“The cold planet is very dark and most of its radiation is in the mid-infrared. Webb is ideal for mid-infrared imaging, but it’s very difficult to do from the ground.”

“We also needed good spatial resolution to distinguish planets from stars in the images, and the large Webb mirror helps a lot in this regard.”

Epsilon Indi Ab is one of the coolest exoplanets ever directly detected, with an estimated temperature of 2 degrees Celsius (35 degrees Fahrenheit). This makes it the coolest planet ever imaged outside the solar system, and cooler than all but one free-floating brown dwarf.

The planet is only about 100 degrees Celsius (180 degrees Fahrenheit) warmer than the gas giants in our solar system.

This provides astronomers with a rare opportunity to study the atmospheric composition of a true solar system analogue.

“Astronomers have imagined there could be planets in this system for decades, and fictional planets orbiting Epsilon Indi have been the setting for Star Trek episodes, novels and video games such as Halo,” Dr Morley said.

“It’s exciting to actually see the planet out there and start measuring its properties.”

Epsilon Indi Ab is the 12th closest exoplanet currently known to Earth and the closest planet with a mass greater than Jupiter.

Astronomers chose to study Epsilon Indi A because the system suggested the possibility of planets, using a technique called radial velocity, which measures the back and forth wobble of the host star along the line of sight.

“We expected there to be a planet in this system because the radial velocity suggested its presence, but the planet we found was different to what we expected,” Dr Matthews said.

“It’s about twice as massive, it’s a little farther from its star, and its orbit is different from what we would expect. We don’t yet know what causes this discrepancy.”

“The planet’s atmosphere also seems to differ slightly from what the models predict.”

“So far, only a few atmospheric photometry measurements have been made, making it difficult to draw any conclusions, but the planet is fainter than expected at shorter wavelengths.”

“This could mean that there is a lot of methane, carbon monoxide and carbon dioxide in the planet’s atmosphere, absorbing shorter wavelengths of light. It could also suggest a very cloudy atmosphere.”

a paper The findings were published in the journal. Nature.

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E.C. Matthews othersA temperate superjupiter photographed in mid-infrared by JWST. NaturePublished online July 24, 2024, doi: 10.1038/s41586-024-07837-8

This article has been edited based on the original NASA release.

Source: www.sci.news

Webb verifies persistent temperature contrast on WASP-39b between morning and evening

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Astronomers used the NASA/ESA/CSA James Webb Space Telescope to obtain and analyze morning and evening transmission spectra of the hot Saturn exoplanet WASP-39b, which orbits a star about 700 light-years away in the constellation Virgo. The spectrum is best explained by a model in which the evening boundary is 177 K hotter than the morning boundary.

This diagram shows what WASP-39b might look like, based on our current understanding of planets. Image credit: NASA/ESA/CSA/Webb/J. Olmsted, STScI.

WASP-39b is a hot gas giant that orbits the G7 type star WASP-39 every 4.1 days.

First discovered in 2011, this alien world has roughly the same mass as Saturn, but is 50% larger.

The planet's extreme expansion is due in part to its high temperature (about 900 degrees Celsius or 1,652 degrees Fahrenheit).

“WASP-39b has become a kind of benchmark planet for the Webb mission's exoplanet atmospheric studies,” said Dr. Nestor Espinoza, an astronomer at the Space Telescope Science Institute.

“The planet has a bulging, puffy atmosphere, so the signal coming from the starlight passing through the planet's atmosphere is quite strong.”

Webb spectra of WASP-39b's atmosphere released so far have revealed the presence of carbon dioxide, sulfur dioxide, water vapor, and sodium, and show the entire day/night boundary, without any detailed attempt to distinguish one from the other.

Now, the new analysis constructs two different spectra from the terminator region, essentially splitting the day/night boundary into two semicircles: one from the evening and one from the morning.

According to Webb's data, evenings will be much hotter, reaching a scorching 800 degrees Celsius (1,450 degrees Fahrenheit), before easing into a cooler 600 degrees Celsius (1,150 degrees Fahrenheit) in the morning.

“It's really amazing that we were able to resolve this small difference, and this is thanks to Webb's sensitivity to near-infrared wavelengths and its extremely stable photometric sensor,” said Dr. Espinoza.

“Any movement of the instrument or the observatory while collecting data would severely limit our ability to make this detection. This has to be exceptionally precise, and Webb is just that precise.”

“We don't have a planet like this in our solar system, but most of the planets we observe orbiting distant stars have shorter orbits and are closer to us, like WASP-39b,” said Dr James Kirk, astronomer at Imperial College London.

“Now we can test theories about these planets and, for the first time, directly measure the morning and evening sides of an exoplanet across a wide range of wavelengths.”

This transmission spectrum, taken with Webb's NIRSpec (Near-Infrared Spectrometer) PRISM in Bright Object Time Series mode, shows the amount of different wavelengths (colors) of near-infrared stellar light blocked by WASP-39b's atmosphere. The spectrum shows clear evidence of water and carbon dioxide on the exoplanet, as well as morning and evening temperature variations. Image credit: NASA / ESA / CSA / Webb / R. Crawford, STScI.

Extensive modeling of the resulting data will also allow researchers to investigate the structure of WASP-39b's atmosphere, its cloud cover, and why it's hotter in the evenings.

While the team plans to next investigate how cloud cover affects temperature, and vice versa, the astronomers confirmed that the main cause of WASP-39b's temperature difference is the circulation of gas around the planet.

For highly irradiated exoplanets that orbit relatively close to their stars, like WASP-39b, researchers typically expect gas to shift as the planet rotates around the star: a strong equatorial jet stream should move hotter gas on the dayside from the evening to the nightside.

Because the temperature difference is so large, the pressure difference is also large, resulting in faster wind speeds.

Using the General Circulation Model, a 3-D model similar to those used to predict weather patterns on Earth, the astronomers found that on WASP-39b, prevailing winds tend to move from the nightside across the morning boundary, around the dayside, across the evening boundary, and then back around the nightside.

As a result, the morning side of the boundary is cooler than the evening side.

In other words, the morning side is hit by winds of air cooled by the night side, and in the evening it is hit by winds of air heated by the day side.

The study suggests that wind speeds on WASP-39b could reach thousands of kilometers per hour.

“This analysis is particularly interesting because it provides previously unavailable 3D information about the planet,” Dr Espinoza said.

“The fact that it's hotter on the evening edge means that it's a bit bulging, which means that in theory there's a little swell at the boundary approaching the night side of the planet.”

of study Published in this week's journal Nature.

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N. Espinosa othersThe uneven boundary surface of exoplanet WASP-39b. NaturePublished online July 15, 2024; doi: 10.1038/s41586-024-07768-4

This article is based on press releases from NASA and Imperial College London.

Source: www.sci.news

New Images of Arp 142 Captured by Webb Show Stunning Detail

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope have captured new infrared images of two interacting galaxies. Alp 142.

This Webb image shows two interacting galaxies known as Arp 142. On the left is NGC 2937, nicknamed “The Egg” because of its appearance, and on the right is NGC 2936, nicknamed “The Penguin” because of its appearance. Image courtesy of NASA/ESA/CSA/Webb/STScI.

The interacting pair, Arp 142, is located about 326 million light-years away in the southern constellation Hydra.

This system is ARP Catalog of Peculiar Galaxies It was observed by astronomer Halton C. Earp in the 1960s.

It contains the star-forming spiral galaxy NGC 2936 and its elliptical companion galaxy NGC 2937 at the lower left, which bears a striking resemblance to a penguin guarding its eggs.

The “penguin” part of the pair, NGC 2936, was probably once a relatively ordinary-looking spiral galaxy – flat like a pancake, with smoothly symmetrical spiral arms.

Because of the abundance of newly formed, hot stars, its shape is twisted and distorted by the gravitational forces of nearby stars.

The twin “egg,” NGC 2937, is a collection of much older stars and, in contrast, is largely featureless.

The absence of glowing red dust features indicates that it long ago lost its reservoir of gas and dust from which new stars could form.

“The two asteroids first came close to each other between 25 million and 75 million years ago, triggering 'fireworks' – the formation of new stars – in the constellation of Penguin,” astronomer Webb said in a statement.

“In the most extreme cases, galaxy mergers could result in the formation of thousands of new stars every year for millions of years.”

“In the case of penguins, studies have found that they form around 100-200 stars per year. By comparison, in our own Milky Way galaxy (which is not interacting with a galaxy of a similar size), around six to seven new stars form per year.”

“This gravitational rocking also changed the penguins' appearance,” they noted.

“The spiral arms uncoiled, pulling gas and dust in different directions like confetti.”

“When galaxies interact, it's rare for individual stars to collide (the universe is huge), but the intermingling of galaxies disrupts the orbits of stars.”

“Currently, the centre of the Penguin's galaxy looks like an eye inside its head, and the galaxy has a prominent star trail in the shape of a beak, spine and fanned-out tail. A faint but noticeable dust ribbon stretches from the beak to the tail.”

“Although the Penguin Galaxy appears much larger than the Egg Galaxy, the two galaxies have roughly the same mass,” the astronomers said.

“This is one of the reasons why the tiny looking egg hasn't merged with the penguin yet.”

“Because the elliptical egg is filled with old stars and contains very little gas or dust, it doesn't emit its own 'streams' or tidal tails, and instead maintains its compact elliptical shape.”

“If you look closely, the Egg has four noticeable diffraction spikes – it's glowing because of a high concentration of stars from the galaxy.”

“Now, find the bright, edge-on galaxy in the upper right. It may look like it's crashing the party, but it’s not close by.”

Cataloging No. 1237172It lies nearly 100 million light-years from Earth. It is relatively young and not covered by dust, making it virtually invisible in Webb's mid-infrared images.”

Source: www.sci.news

Webb Observes Four Views of a Gravitationally Lensed Quasar

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The quasar, called RX J1131-1231, lies about 6 billion light-years away in the constellation Crater.

This Webb image shows the galaxy RX J1131-1231 distorted by gravitational lensing into a dark ring. At the top of the ring are three very bright spots next to each other, emitting diffraction spikes. These are copies of a single quasar in the lensed galaxy, duplicated by gravitational lensing. In the center of the ring, the lensing elliptical galaxy appears as a small blue spot. Image credit: NASA / ESA / CSA / Webb / A. Nierenberg.

RXJ1131-1231 The galaxy is thought to be one of the best lensed quasars ever discovered, as the foreground lensing effect blurs the image of the background quasar into a bright arc, creating four celestial images.

“Gravitational lensing effect“This phenomenon, first predicted by Albert Einstein, acts as a natural telescope, magnifying the light from these sources and providing a rare opportunity to study the regions close to the black holes in distant quasars,” astronomer Webb said.

“All matter in the universe distorts the space around it, and the more mass there is, the more pronounced this effect.”

“Around very massive objects like galaxies, light passing nearby travels through this distorted space, appearing to bend visibly from its original path.”

“One of the inevitable effects of gravitational lensing is the magnification of distant objects, allowing astronomers to study objects that would otherwise be too faint or too far away.”

“Measuring the X-ray emission from a quasar can provide an indication of how fast the central black hole is rotating, which could give researchers important clues about how black holes grow over time,” the researchers added.

“For example, if black holes grow primarily through collisions and mergers between galaxies, then the accumulation of material in a stable disk and the steady supply of new material from the disk should cause the black hole to rotate rapidly.”

“On the other hand, if a black hole grows through many small accretion episodes, then material will accumulate from random directions.”

“Observations show that the black hole in RX J1131-1231 is rotating at more than half the speed of light, suggesting that the black hole grew by merging rather than by attracting matter from different directions.”

New images of RX J1131-1231 can be found at Webb's MIRI (Mid-Infrared Instrument) As part of an observational program to study dark matter.

“Dark matter is an invisible substance that makes up most of the mass of the universe,” the researchers said.

“Webb's quasar observations allow us to probe the nature of dark matter on smaller scales than ever before.”

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This article is a version of a press release provided by NASA.

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Webb finds hourglass-shaped molecular cloud surrounding protostar

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Astronomers MIRI (mid-infrared measuring instrument) camera The NASA/ESA/CSA James Webb Space Telescope probe has captured striking new photos of molecular cloud L1527.

L1527, shown in this image from Webb's MIRI instrument, is a molecular cloud enveloping the IRAS 04368+2557 protostar. The more diffuse blue light and filamentary structures in the image come from organic compounds called polycyclic aromatic hydrocarbons (PAHs), while the red in the center of the image is a thick layer of energetic gas and dust that surrounds the protostar. The white intermediate regions are a mix of PAHs, ionized gases, and other molecules. Image courtesy of NASA / ESA / CSA / STScI.

L1527, also known as LDN 1527, is located about 447 light-years from Earth in the constellation Taurus.

The young protostar, called IRAS 04368+2557, is embedded in a molecular cloud that is part of a star-forming region in the constellation Taurus.

IRAS 04368+2557 is a relatively young star, only 100,000 years old.

Given its age and brightness in the far-infrared, the star is likely a class 0 protostar, the earliest stage of star formation.

IRAS 04368+2557 has an edge-on disc with two misaligned parts.

The inner and outer parts of the disk have slightly different orbital planes and are connected at 40 to 60 AU (astronomical units) from the protostar, but the disk is point-symmetric with respect to the location of the protostar.

Webb's previous observations of L1527 showed that NIRCam (Near Infrared Camera)Astronomers were able to peer into the region, where the molecular cloud and protostar appeared in opaque, vibrant colors.

Both NIRCam and MIRI show the effects of outflows that shoot out in opposite directions along the protostar's rotation axis as the protostar consumes gas and dust from the surrounding cloud.

These outflows take the form of bow shock waves relative to the surrounding molecular cloud and appear as filament-like structures throughout the molecular cloud.

They also energize, or excite, the material around them, causing the areas above and below them to glow, imprinting bright hourglass structures in the molecular cloud.

“But unlike NIRCam, which primarily images light reflected from dust, MIRI will be able to probe how these outflows affect the thickest dust and gas in the region,” astronomer Webb said in a statement.

“The blue region that takes up most of the hourglass represents carbonaceous molecules called polycyclic aromatic hydrocarbons.”

“The IRAS 04368+2557 protostar itself is shown in red, along with the dense mixture of dust and gas that surrounds it.”

“Meanwhile, MIRI revealed white regions just above and below the protostar, which are not as clearly visible in the NIRCam view.”

“This region is a mixture of hydrocarbons, ionized neon, and thick dust, indicating that the protostar is consuming material from the disk in a promiscuous manner, pushing this material over great distances.”

“As IRAS 04368+2557 continues to age and emits energetic jets, it will consume, destroy or push aside much of this molecular cloud, and much of the structure seen here will begin to disappear.”

“Eventually, when the accumulation of mass stops, this impressive spectacle will come to an end and the star itself will become more clearly visible to optical telescopes.”

“Combining both near-infrared and mid-infrared analyses will shed light on the overall behavior of this system, including how the central protostar is influencing the surrounding region.”

“Other stars in Taurus, the star-forming region in which L1527 resides, may form in exactly this way, which could lead to the disruption of other molecular clouds, either preventing the formation of new stars or promoting their development.”

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Webb studies the intricate makeup of Jupiter’s ionosphere

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Jupiter’s upper atmosphere consists of a neutral thermosphere and an electrically charged ionosphere. Astronomers using the NASA/ESA/CSA James Webb Space Telescope have discovered unexpected small-scale intensity features, including arcs, bands, and spots, in the low-latitude ionosphere in the region above Jupiter’s Great Red Spot.

This illustration shows the region observed by Webb, first with its location on the NIRCam image of the entire planet (left), and then the region itself as imaged by Webb’s Near-Infrared Spectrometer (NIRSpec) (right). Image credit: NASA / ESA / CSA / Webb / Jupiter ERS Team / J. Schmidt / H. Melin / M. Zamani, ESA and Webb.

Jupiter is one of the brightest objects in the night sky and can be easily seen on a clear night.

Apart from the bright Northern and Southern Lights at Jupiter’s poles, the glow from Jupiter’s upper atmosphere is weak, making details in this region difficult to discern with ground-based telescopes.

But Webb’s infrared sensitivity has allowed scientists to study the upper atmosphere of the infamous Great Red Spot in unprecedented detail.

The upper atmosphere of this gas giant is the interface between the planet’s magnetic field and the atmosphere below it.

Here you can see the bright and vibrant aurora borealis and southern lights, created by volcanic material erupting from Jupiter’s moon Io.

However, as one approaches the equator, the structure of the planet’s upper atmosphere is influenced by incoming sunlight.

Because Jupiter receives only 4% of the sunlight that Earth does, astronomers predicted that this region would be essentially homogeneous.

Astronomer Henrik Melin of the University of Leicester and his colleagues observed the Great Red Spot in July 2022 using an Integral Field Unit. Webb’s near-infrared spectrometer (NIR Spec).

Their early public science observations aimed to investigate whether this region was in fact dull, and the region above the iconic Great Red Spot was the subject of Webb’s observations.

They were surprised to find that the upper atmosphere contains a variety of complex structures, including dark arcs and bright spots across the entire field of view.

“We probably naively thought this area would be really boring. It’s actually just as interesting, if not more so, than the Northern Lights. Jupiter never fails to surprise us,” Dr Melin said.

The light emitted from this region is driven by sunlight, but the team suggests there must be another mechanism that changes the shape and structure of the upper atmosphere.

“One way this structure can be altered is by gravity waves, similar to how waves crashing on the shore create ripples in the sand,” Dr Melin said.

“These waves originate deep within the turbulent lower atmosphere around the Great Red Spot and can rise in altitude to alter the structure and emissions of the upper atmosphere.”

“These atmospheric waves are occasionally observed on Earth, but they are much weaker than those Webb observed on Jupiter.”

“In the future, we hope to carry out follow-up webbed observations of these complex wave patterns and investigate how they move within the planet’s upper atmosphere to improve our understanding of the energy budget of this region and how its features change over time.”

of Investigation result Published in a journal Natural Astronomy.

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H. Melin othersIrregularities in Jupiter’s ionosphere observed by JWST. Nat AstronPublished online June 21, 2024, doi: 10.1038/s41550-024-02305-9

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Webb finds early universe protoglobular cluster

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope have discovered at least five young globular clusters within SPT 0615-JD1 (also known as the Cosmic Gems Arc), a strongly lensed galaxy that existed when the universe was 460 million years old.

These images show the galaxy cluster SPT-CL J0615-5746 (right) and part of this cluster (left), showing two clearly lensed galaxies. The Cosmic Gems arc is shown along with several galaxy clusters. Images courtesy of NASA / ESA / CSA / Webb / L. Bradley, STScI / A. Adamo, Stockholm University / Cosmic Spring Collaboration.

“These galaxies are thought to be the main source of intense radiation that reionized the early universe,” said Dr Angela Adamo, astronomer at Stockholm University and the Oskar Klein Centre.

“What’s special about the Cosmic Gems Ark is that thanks to gravitational lensing, we can actually resolve galaxies down to the parsec scale.”

SPT 0615-JD1 was originally discovered in Hubble Space Telescope images obtained by the RELICS (Reionizing Lensing Cluster Survey) program of the lensing galaxy cluster SPT-CL J0615-5746, located about 7.7 billion light-years away in the constellation of Scorpio.

The Webb telescope will enable Dr Adamo and his colleagues to see where stars are forming and how they are distributed, in a similar way that the Hubble telescope is used to study the local galaxy.

Webb’s observations provide a unique opportunity to study star formation and the internal structure of young galaxies at unprecedented distances.

“The combination of the Webb Telescope’s incredible sensitivity and angular resolution at near-infrared wavelengths, along with gravitational lensing by a large foreground galaxy cluster, made this discovery possible that would not have been possible with any other telescope,” said Dr. Larry Bradley, an astronomer at the Space Telescope Science Institute.

“The surprise and excitement I felt when I first opened the Webb images was overwhelming,” Dr. Adamo said.

“We saw a string of tiny bright dots projected from one side to the other. These cosmic gems are star clusters.”

“Without Webb, we would never have known we were observing star clusters in such a young galaxy.”

Astronomers say the discovery connects different scientific disciplines.

“These results provide direct evidence of the formation of protoglobular clusters in faint galaxies during periods of reionization and help us understand how these galaxies successfully reionized the Universe,” Dr Adamo said.

“This discovery also places important constraints on the formation of globular clusters and their early properties.”

“For example, the high stellar densities found in galaxy clusters provide the first indications of processes occurring within them and give new insights into the possible formation of very massive stars and black hole seeds that are important for the evolution of galaxies.”

In the future, the team hopes to construct a sample of galaxies that can achieve a similar resolution.

“I am convinced that there are more such systems in the early universe waiting to be discovered, which will improve our understanding of early galaxies even further,” said Dr Eros Vanzella, astronomer at the Bologna Observatory for Astrophysics and Space Sciences (INAF).

of Investigation result Published in today’s journal Nature.

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A. Adamo othersA bound star cluster observed in a lensed galaxy 460 million years after the Big Bang. NaturePublished online June 24, 2024, doi: 10.1038/s41586-024-07703-7

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Webb uncovers puzzling alignment of protostellar outflows in the Ophiuchus Nebula

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These protostellar outflows form when jets of gas from the newborn star collide with nearby gas and dust at high speeds, and the objects typically point in different directions within a single region. Serpens NebulaBut like sleet falling during a storm, they all lean in the same direction and to the same degree.

This Webb image shows a collection of outflows from a line of protostars in one small region (upper left corner) of the Ophiuchus Nebula. Image credit: NASA / ESA / CSA / STScI / K. Pontoppidan, NASA Jet Propulsion Laboratory / J. Green, Space Telescope Science Institute.

“So how does the alignment of a stellar jets relate to the star's rotation?” said Webb.

“When interstellar gas clouds collapse to form stars, they rotate faster.”

“The only way for the gas to keep moving inward is to remove some of its spin (called angular momentum).”

“A disk of material forms around the young star, carrying material downward like a vortex around a drain.”

“The swirling magnetic fields within the inner disk cause some of the material to be ejected as twin jets, erupting outward in opposite directions, perpendicular to the disk of material.”

“In Webb's images, these jets are identified by bright red lumpy streaks, which are shock waves created when the jets collide with the surrounding gas and dust.”

“Here, the red color indicates the presence of molecular hydrogen and carbon monoxide.”

“Webb will be able to image these very young stars and their outflows, which have previously been blocked at visible wavelengths of light.”

“There are several forces that can change the direction of the outflow during this period in the young star's life.”

“One way is that the binary stars rotate around each other, causing them to wobble, twisting the direction of the outflow over time.”

The Serpens Nebula is a so-called reflection nebula located about 1,300 light-years away in the constellation Serpens.

The object is estimated to be between 1 and 2 million years old, making it very young in cosmic terms.

“The Serpens Nebula contains a particularly dense cluster of protostellar clusters (approximately 100,000 years old) at the center of this image, some of which will eventually grow to the mass of the Sun,” the astronomers said.

“It's a reflection nebula, meaning it's a cloud of gas and dust that doesn't emit its own light but glows by reflecting light from nearby and internal stars.”

“Thus, throughout the field of this image, the filaments and lint of different hues represent reflected light from protostars still forming within the cloud.”

“In some areas there is dust in front of that reflection, which shows up here as a diffuse shade of orange.”

“There have been several other serendipitous discoveries in the region, including the shadow of a flapping bat, so named because 2020 data from the NASA/ESA Hubble Space Telescope revealed it to be flapping, or migrating. This feature is visible in the centre of the Webb image.”

of Investigation result Published in Astrophysical Journal.

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Joel D. Green others2024. Why are (almost) all of the protostar outflows aligned with Serpens Main? ApJin press.

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Webb Reveals the Inner Workings of the Crab Nebula

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The NASA/ESA/CSA James Webb Space Telescope has provided stunning new images of the Crab Nebula, containing the highest-quality infrared data yet available to help astronomers investigate the detailed structure and chemical composition of this supernova remnant.

Webb's detailed analysis of the Crab Nebula's structure has helped astronomers continue to evaluate the leading theories about the origin of supernova remnants. Image credit: NASA/ESA/CSA/STScI/T. Temim, Princeton University.

The Crab Nebula is the result of a supernova explosion observed in 1054 AD by Chinese, Japanese, Arab and Native American astronomers.

Bright enough to be seen in amateur telescopes, this beautiful nebula lies 6,500 light-years away in the constellation Taurus.

Also known as Messier 1, NGC 1952, or Taurus A, the galaxy was first identified in 1731 by British astronomer, physician, and electrical researcher John Bevis.

In 1758, French astronomer Charles Messier rediscovered the faint nebula while searching for comets, and later added it to his celestial catalog as a “false comet” named Messier 1.

The nebula got its name from an 1844 drawing by Irish astronomer Lord Rosse.

The Crab Nebula is extremely unusual: its atypical composition and extremely low explosion energy had previously led astronomers to believe it was an electron-capture supernova, a rare type of explosion that occurs from a star with a less-evolved core made of oxygen, neon, and magnesium, rather than the more common iron nucleus.

Previous studies have calculated the total kinetic energy of the explosion based on the volume and velocity of the current ejecta.

Astronomers have estimated that the explosion had a relatively low energy (less than one-tenth the energy of a typical supernova) and that the source star's mass was in the range of eight to ten times that of the Sun, lying on the fine line between stars that undergo violent supernova explosions and those that do not.

However, there are contradictions between the electron capture supernova theory and observations of the Scorpio Nebula, especially the observed rapid motion of the pulsar.

In recent years, astronomers have also come to understand more about iron-collapse supernovae, leading them to believe that these types of supernovae could also produce low-energy explosions if the star's mass is low enough.

To reduce uncertainties about the nature of the Crab Nebula's protostar and explosion, Tee Temim of Princeton University and his colleagues used Webb's spectroscopy capabilities to zero in on two regions within the Crab Nebula's inner filament.

Theory predicts that due to the different chemical composition of the cores of electron capture supernovae, the abundance ratio of nickel to iron (Ni/Fe) should be much higher than that measured in the Sun, which contains these elements from earlier generations of stars.

Studies in the 1980s and early 1990s used optical and near-infrared data to measure the Ni/Fe ratios in the Crab Nebula and recorded high Ni/Fe abundances that seemed to favor an electron capture supernova scenario.

With its sensitive infrared capabilities, the Webb Telescope is currently advancing research into the Crab Nebula.

The study authors leveraged Webb's spectroscopic capabilities. Milli (mid-infrared instrument) to measure nickel and iron emission lines to get a more reliable estimate of the Ni/Fe abundance ratio.

They found that while this ratio is still high compared to the Sun, it is only slightly higher and much lower than previous estimates.

The revised value is consistent with electron capture, but does not exclude the possibility of iron-collapse explosions from low-mass stars as well.

High-energy explosions from more massive stars would produce Ni/Fe ratios closer to the solar abundance.

Further observational and theoretical work will be needed to distinguish between these two possibilities.

Webb extracted spectral data from two small regions within the Crab Nebula to measure abundances, and also observed the remnant's larger environment to understand the details of synchrotron radiation and dust distribution.

The images and data collected by MIRI allowed astronomers to isolate dust emissions within the Crab Nebula and map them in high resolution for the first time.

“By mapping the warm dust emissions with Webb and combining it with data on cold dust particles from NASA's Herschel Space Telescope, we have created a comprehensive picture of the dust distribution, with the outermost filaments containing relatively warm dust and cold particles spread out near the center,” the team said.

a paper The paper on the survey results is Astrophysical Journal Letters.

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Teatemimu others2024. JWST analysis of the Crab Nebula: Ni/Fe abundance constraints on pulsar winds, dust filaments, and explosion mechanisms. Apu JL 968, L18; Source: 10.3847/2041-8213/ad50d1

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Webb discovers massive collision in Beta Pictoris star system

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope discovered a giant asteroid impact around Beta Gactris, the second brightest star in the constellation Scorpio.

Chen othersBeta Pictoris has a dynamic circumstellar environment, suggesting that periods of active collisions could produce large dust clouds that could blow through the planetary system and increase dust accretion to the giant planets Beta Pictoris b and c. Image credit: Roberto Molar Candanosa / Johns Hopkins University / Lynette Cook / NASA.

Beta Pictoris is an A5 type star located in the constellation Pictoris, approximately 63 light years from Earth.

The star has a mass about 1.8 times that of the Sun and is only 20 million years old.

It contains a circumstellar disk of gas and dust, numerous comet-like objects, and two giant planets, Beta Pictoris b and Beta Pictoris c.

Beta Pictoris b is a gas giant with a mass about 9-13 times that of Jupiter. It orbits its parent star at a distance of 9.8 astronomical units (AU) and completes one revolution around its parent star every 22 years.

Beta Pictoris c has a mass 8.2 times that of Jupiter and is located quite close to its star, orbiting it at a distance of 2.7 AU with an orbital period of about 1,200 days.

“Beta Pictoris is at an age where terrestrial planetary belt planet formation is still ongoing due to giant asteroid impacts, so what we're seeing here is essentially how rocky planets and other objects are forming in real time,” said Dr Christine Chen, an astronomer at Johns Hopkins University.

By comparing the new data with data from the Webb Space Telescope in 2004 and 2005, Dr Chen and his colleagues found a significant change in the energy characteristics emitted by the dust particles around Beta Pictoris.

Webb's detailed measurements allowed the researchers to track the composition and size of dust particles in the very region that Spitzer had previously analyzed.

The researchers focused on heat given off by crystalline silicates – minerals commonly found around young stars, on Earth and other celestial bodies – and found no trace of the particles observed in 2004 and 2005.

“This suggests that a catastrophic collision occurred between the asteroid and another object about 20 years ago, shattering the asteroid into microscopic dust particles smaller than pollen or powdered sugar,” Dr Chen said.

“We believe the dust is the same as that first observed in Spitzer data in 2004 and 2005.”

“The best explanation given by Webb's new data is that we have in fact witnessed the aftermath of a rare catastrophe between large, asteroid-sized objects, completely changing our understanding of this solar system.”

The new data suggests that dust dispersed outward by radiation from the system's central star can no longer be detected.

Initially, dust near the star heated up and emitted thermal radiation that Spitzer's instruments identified.

Now, as the dust cools away from the star, it no longer emits its thermal properties.

When Spitzer collected its previous data, scientists assumed that small objects abrading the ground would stir up the dust and steadily replenish it over time.

But Webb's new observations showed that the dust had disappeared and not been replaced.

“The amount of dust kicked up is about 100,000 times the size of the asteroid that wiped out the dinosaurs,” Dr Chen said.

The authors, Investigation result this week's 244th Meeting of the American Astronomical Society In Madison, Wisconsin.

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Christine Chen others2024. Spectroscopic evidence of a recent giant impact around Beta. 224 AustraliaAbstract number 313

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Webb uncovers high levels of hydrocarbons in protoplanetary disks surrounding ultra-low-mass stars

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Very low-mass stars orbit rocky exoplanets more frequently than other types of stars. The composition of these planets is poorly understood, but it is thought to be related to the protoplanetary disk in which they form. In the new study, astronomers used the NASA/ESA/CSA James Webb Space Telescope to investigate the chemical composition of the planet-forming disk around ISO-ChaI 147, a red dwarf star just one-tenth the mass of the Sun. They identified emission from 13 carbon-containing molecules, including ethane and benzene.

This is an artist's impression of a young star surrounded by a disk of gas and dust. Image courtesy of NASA/JPL.

ISO-ChaI 147 It is a red dwarf star with a mass 0.11 times that of the Sun, located about 639 light years away in the constellation Chamaeleon.

The star was observed as part of the MIRI Mid-Infrared Disk Survey (MINDS), which aims to bridge the gap between the chemical composition of the disk and the properties of exoplanets.

These observations provide insight into the environments and fundamental elements for the formation of such planets.

Astronomers discovered that the gas in ISO-ChaI 147's planet-forming region is rich in carbon.

This could be due to carbon being removed from the solid material from which rocky planets form, which could explain why Earth is relatively carbon-poor.

“WEBB has greater sensitivity and spectral resolution than conventional infrared space telescopes,” said Dr Aditya Arabavi, an astronomer at the University of Groningen.

“These observations are not possible from Earth because the radiation is blocked by the atmosphere.”

“So far we have only been able to identify acetylene emissions from this object.”

“But Webb's high sensitivity and spectral resolution allowed us to detect faint emissions from fewer molecules.”

“Thanks to Webb, we now know that these hydrocarbon molecules are not only diverse, but abundant as well.”

The spectrum of ISO-ChaI 147 shows the richest hydrocarbon chemical composition ever observed in a protoplanetary disk, consisting of 13 carbon-containing molecules. Image credit: NASA/ESA/CSA/Ralf Crawford, STScI.

The spectrum of ISO-ChaI 147 is Webb's mid-infrared measuring instrument (MIRI) displays the richest hydrocarbon chemical composition ever observed in a protoplanetary disk, consisting of 13 carbon-containing molecules up to benzene.

This includes the first extrasolar detection of ethane, the largest fully saturated hydrocarbon detected outside the solar system.

Fully saturated hydrocarbons are expected to form from more basic molecules, so detecting them here can give researchers clues about their chemical environment.

Astronomers also detected ethylene, propyne, and methyl radicals in a protoplanetary disk for the first time.

“These molecules have already been detected in our solar system, for example in comets such as 67P/Churyumov-Gerasimenko and C/2014 Q2 (Lovejoy),” Dr. Arababi said.

“It's amazing that we can now see these molecules dancing in the cradle of the planet.”

“This is a completely different environment to how we normally think of planet formation.”

The team note that these results have significant implications for the astrochemistry within 0.1 AU and the planets that form there.

“This is very different to the composition found in disks around solar-type stars, where oxygen-containing molecules (such as carbon dioxide and water) dominate,” said Dr Inga Kamp, also from the University of Groningen.

“This object proves that these are unique classes of objects.”

“It's incredible that we can detect and quantify the amount of a molecule that's well known on Earth, such as benzene, in an object more than 600 light years away,” said Dr Agnes Perrin, an astronomer at the French National Center for Scientific Research.

Team result Published in today's journal Science.

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AM Arabavi other2024. Abundant hydrocarbons present in a disk around a very low-mass star. Science 384, 6700: 1086-1090; doi: 10.1126/science.adi8147

Source: www.sci.news

Webb finds the farthest galaxy ever recorded

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Astronomers NIR Specs The NASA/ESA/CSA James Webb Space Telescope (Near-Infrared Spectrometer) instrument Obtained Spectrum of the record-breaking galaxy JADES-GS-z14-0, observed just 290 million years after the Big Bang. Redshift It’s about 14, a measure of how much the galaxy’s light has been stretched by the expansion of the universe.

This infrared image from Webb’s NIRCam shows the record-breaking galaxy JADES-GS-z14-0. Image credit: NASA / ESA / CSA / STScI / B. Robertson, UC Santa Cruz / B. Johnson, CfA / S. Tacchella, Cambridge / P. Cargile, CfA.

JADES-GS-z14-0, located in the constellation Fornax, JWST: Advanced Deep Extragalactic Exploration (Jade).

The galaxy is much brighter than expected, with a resolved radius of 260 parsecs (848 light years).

The discovery proves that luminous galaxies were already in existence 300 million years after the Big Bang, and that they are more common than expected before Webb.

“The Webb instrument is designed to discover and understand the oldest galaxies, and in its first year of observing as part of JADES, it has found hundreds of candidate galaxies spanning the first 650 million years after the Big Bang,” said Dr. Stefano Carniani of the École Normale Supérieure in Pisa, Italy, and Dr. Kevin Hainline of the University of Arizona, Tucson.

“Early in 2023, we discovered a galaxy in our data with strong evidence of being at a redshift greater than 14. This was very exciting, but some properties of its source made us wary.”

“The source was incredibly bright, something not expected in such a distant galaxy, and it was so close to another galaxy that the two appeared to be part of a single, larger object.”

“When Webb observed the source again in October 2023 as part of the JADES Origins Field, NIR Cam (Near-infrared camera) filters further supported the high-redshift hypothesis.”

“We knew we needed a spectrum, because anything we learn would be of immense scientific importance, either as a new milestone in Webb’s study of the early universe or as a mysterious outlier in a middle-aged galaxy.”

“In January 2024, NIRSpec observed JADES-GS-z14-0 for almost 10 hours, and when the spectrum was first processed, there was unequivocal evidence that the galaxy is indeed at redshift 14.32, breaking the previous record for the most distant galaxy, JADES-GS-z13-0.”

“Seeing this spectrum was very exciting for the whole team, given that its source remained a mystery.”

“This discovery was not just a new distance record for our team. The most important thing about JADES-GS-z14-0 is that it shows that at this distance, this galaxy must be intrinsically very luminous.”

“The images show that the source is more than 1,600 light-years in diameter, proving that the light we are seeing is coming primarily from young stars, and not from the vicinity of a growing supermassive black hole.”

“This much starlight suggests that the galaxy’s mass is hundreds of millions of times that of the Sun!”

“This raises the question: How could nature create such a bright, massive and large galaxy in less than 300 million years?”

“The data reveal other important aspects of this remarkable galaxy,” the astronomers said.

“We found that the galaxy’s color is not inherently blue, which indicates that even at its very earliest stages, some of its light is being reddened by dust.”

They also confirmed that JADES-GS-z14-0 was detected at Webb’s longer wavelengths. Milli (mid-infrared observation instrument), a remarkable achievement considering its distance.

MIRI’s observations cover wavelengths of light emitted in the visible range that are redshifted and cannot be seen by Webb’s near-infrared instrument.

According to the analysis, the brightness of the source suggested by the MIRI observations exceeds that estimated from measurements by other Webb instruments, indicating the presence of strong ionized gas emission in the galaxy in the form of bright emission lines from hydrogen and oxygen.

The presence of oxygen so early in the galaxy’s life was surprising, suggesting that several generations of very massive stars had already died before the galaxy was observed.

“Taken together, all these observations show that JADES-GS-z14-0 is different from the types of galaxy predicted to exist in the early universe by theoretical models and computer simulations,” the researchers said.

“Given the observed luminosity of a source, we can predict how it will grow over cosmic time. So far, we have not found a suitable analogue among the hundreds of other galaxies we have observed at high redshifts in our survey.”

“Because the region of sky we searched to find JADES-GS-z14-0 is relatively small, its discovery has a significant impact on the predicted number of luminous galaxies seen in the early universe, as discussed in a separate, concurrent JADES study.”

“Webb’s observations will enable astronomers to discover many more such luminous galaxies over the next decade, and perhaps sooner.”

“We’re excited to see the incredible diversity of galaxies present in Cosmic Dawn!”

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Stefano Carniani others2024. A shining cosmic dawn: spectroscopic confirmation of two luminous galaxies at z ∼ 14. arXiv:2405.18485

Source: www.sci.news

Webb focuses on irregular galaxy NGC 4449

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope have captured stunning new photos of NGC 4449, located in the constellation Canes Venatici.

This Webb/MIRI/NIRCam image shows the center of irregular galaxy NGC 4449. Image credit: NASA / ESA / CSA / Webb / A. Adamo, Stockholm University / FEAST JWST Team.

NGC 4449 It is located about 12.5 million light years away in the constellation Canes Venatici.

Also known as Caldwell 21, LEDA 40973, and UGC 7592, the galaxy has a diameter of about 20,000 light-years.

NGC 4449 discovered It was discovered on April 27, 1788 by German-born British astronomer William Herschel.

It is part of the M94 galaxy group, lie It is near the Local Group that hosts our Milky Way galaxy.

“NGC 4449 has been forming stars for billions of years, but star formation is occurring at a much higher rate today than in the past,” astronomer Webb said.

“Such unusually explosive and intense star formation activity is called a starburst, and NGC 4449 is therefore known as a starburst galaxy.”

“Indeed, at the current rate of star formation, the gas supply required for star formation will last only another billion years or so.”

“Starbursts typically occur in the centres of galaxies, but NGC 4449 shows more widespread star formation activity, with very young stars observed both in the galaxy's core and in the outflow that surrounds it.”

“The current widespread starburst is likely caused by an interaction or merger with a smaller companion star.”

“Indeed, star formation in NGC 4449 is likely influenced by interactions with several nearby stars.”

“NGC 4449 resembles a primitive star-forming galaxy that grew by merging and accreting with smaller stellar systems,” the researchers added.

“NGC 4449 is close enough for us to observe it in great detail, making it an ideal laboratory for studying what happened during the formation and evolution of galaxies in the early universe.”

This Webb/NIRCam image shows the irregular galaxy NGC 4449. Image courtesy of NASA / ESA / CSA / Webb / A. Adamo, Stockholm University / FEAST JWST Team.

NGC 4449 was observed as part of the FEAST (Feedback in Emerging extrAgalactic Star cluSTers) survey.

The image is MIRI on the Web (mid-infrared measuring instrument) and NIR Cam (Near infrared camera) equipment.

“Infrared observations reveal the galaxy's crawling tentacles of gas, dust and stars,” the astronomers said.

“The bright blue dots reveal countless individual stars, while the bright yellow regions spread across the galaxy show concentrated active stellar nurseries where new stars are forming.”

“The orange-red areas show the distribution of a type of carbon-based compound known as polycyclic aromatic hydrocarbons (PAHs). The MIRI F770W filter is particularly well suited to imaging these important molecules.”

“The bright red spots correspond to hydrogen-rich regions that have been ionized by radiation from newly formed stars.”

“The diffuse gradient of blue light around the central region indicates the distribution of old stars.”

“The compact light blue regions within the red ionized gas are concentrated mainly in the outer regions of the galaxy and represent the distribution of young star clusters.”

Source: www.sci.news

Webb captures stunning image of the Horsehead Nebula

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope have captured the most detailed images ever of the Horsehead Nebula, one of the most distinctive objects in our sky.

At the bottom of this Web/NIRCam image, a small portion of the Horsehead Nebula is visible up close as a curved wall of thick, smoky gas and dust. Above the nebula, various distant stars and galaxies can be seen all the way to the top of the image. Image credits: NASA / CSA / ESA / Webb / K. Misselt, University of Arizona / A. Abergel, IAS, Université Paris-Saclay, CNRS.

The Horsehead Nebula is located in the constellation Orion, about 1,500 light-years from Earth.

Also known as Barnard 33, this nebula is visible only because its indistinct dust is silhouetted against the brighter nebula IC 434.

The Horsehead Nebula is just one small feature of the Orion Molecular Cloud Complex, with the glowing Flame Nebula dominating the center of this view.

The nebula was first recorded by Scottish astronomer Williamna Fleming on February 6, 1888.

The object is formed by a collapsing cloud of interstellar matter and shines in the light of a nearby hot star.

The gas cloud surrounding the horsehead has now disappeared, but the protruding columns are made of stronger material that is less erodible.

Astronomers estimate that the Horsehead Formation has about 5 million years left to collapse.

The new image from the web focuses on the upper illuminated edge of the nebula’s characteristic dust and gas structures.

This Webb/MIRI image is more than half filled from bottom to top with a small section of the Horsehead Nebula. Image credits: NASA / CSA / ESA / Webb / K. Misselt, University of Arizona / A. Abergel, IAS, Université Paris-Saclay, CNRS.

“The Horsehead Nebula is well known. photodissociation region (PDR),” astronomer Webb said.

“In such regions, ultraviolet light from young massive stars creates a region of warm, nearly neutral gas and dust between the fully ionized gas around the massive star and the clouds they are born into. .”

“This UV radiation has a strong effect on the gas chemistry in these regions and acts as the most important heat source.”

“These regions occur where the interstellar gas is concentrated enough to remain neutral, but not dense enough to prevent the transmission of deep ultraviolet light from massive stars.”

“Light emitted from such PDRs will be used to study the physical and chemical processes that drive the evolution of the interstellar medium in our galaxy and throughout the universe from the early days of active star formation to the present day. We provide unique tools for

“The Horsehead Nebula, due to its close proximity and near-edge-on geometry, provides an opportunity for astronomers to study the physical structure of the PDR and the evolution of the chemical properties of gas and dust within their respective environments and transition regions. is an ideal target for “among them. “

“This is considered one of the best objects to study how radiation interacts with the interstellar medium.”

“Thanks to Mr. Webb. mm (mid-infrared measuring instrument) and NIRCam “We used (near-infrared camera) equipment to reveal for the first time small-scale structures at the end of an illuminated horsehead,” they said.

“We also detected a network of stripes extending perpendicular to the PDR front and containing dust particles and ionized gas entrained in the nebula's photoevaporative flow.”

“These observations allowed us to investigate the effects of dust attenuation and ejection, and to better understand the multidimensional shape of the nebula.”

“Next, we will study the spectroscopic data obtained from the nebula to demonstrate the evolution of the physical and chemical properties of the material observed throughout the nebula.”

of result appear in the diary astronomy and astrophysics.

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A. Abergel other. 2024. His JWST observations of the horsehead photon-dominated region I. First results from multiband near-infrared and mid-infrared imaging. A&A, in press. doi: 10.1051/0004-6361/202449198

Source: www.sci.news

Cool brown dwarf emits methane detected by Webb

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Astronomers using the NASA/ESA/CSA James Webb Space Telescope detected methane emissions from the. CWISEP J193518.59-154620.3 (W1935 for short) is an isolated brown dwarf star with a temperature of about 482 K. Their findings also suggest that W1935 could produce auroras similar to those seen on our planet, Jupiter, and Saturn.

Artist's impression of the brown dwarf W1935. Image credit: NASA/ESA/CSA/L. Hustak, STScI.

W1935 is located about 47 light-years away in the constellation Sagittarius.

This brown dwarf was co-discovered by Backyard Worlds: Planet 9 citizen science volunteer Dan Caselden and NASA's CatWISE team.

W1935's mass is not well known, but it is probably in the range of 6 to 35 times the mass of Jupiter.

After observing numerous brown dwarfs observed by Webb, Dr. Jackie Faherty Researchers at the American Museum of Natural History found W1935 to be similar, with one notable exception. It was emitting methane, which had never been seen before in brown dwarfs.

“Methane gas is expected to be present in giant planets and brown dwarfs, but we typically see it absorbing light rather than absorbing it,” Faherty said.

“At first we were confused by what we were seeing, but eventually it turned into pure excitement when it was discovered.”

Computer modeling provided another surprise. W1935 may have a temperature inversion, a phenomenon in which the atmosphere becomes warmer as altitude increases.

Temperature inversions easily occur in planets orbiting stars, but brown dwarfs are isolated and have no obvious external heat source.

“We were pleasantly shocked when the model clearly predicted a temperature inversion,” said Dr Ben Burningham, an astronomer at the University of Hertfordshire.

“But we also needed to figure out where that extra upper atmosphere heat was coming from.”

To find out, astronomers turned to our solar system. In particular, they focused on the study of Jupiter and Saturn. Both show methane release and temperature inversions.

Since the aurora is likely the cause of this feature on the solar system's giants, the researchers speculated that they had discovered the same phenomenon in W1935.

Planetary scientists know that one of the main drivers of Jupiter and Saturn's auroras are high-energy particles from the sun that interact with the planets' magnetic fields and atmospheres, heating the upper layers.

This is also the reason for the aurora borealis we see on Earth. Auroras are most unusual near the poles, so they are commonly referred to as aurora borealis or southern lights.

However, W1935 does not have a host star, so solar wind cannot contribute to the explanation.

There's another fascinating reason why auroras occur in our solar system.

Both Jupiter and Saturn have active moons that occasionally eject material into space, interacting with the planets and enhancing the auroral footprints of those worlds.

Jupiter's moon Io is the most volcanically active world in the solar system, spewing fountains of lava tens of miles high. Also, Saturn's moon Encereadus spews water vapor from geysers that freeze and boil as soon as they reach space.

Although more observations are needed, researchers speculate that one explanation for W1935's aurora may be an active moon that has yet to be discovered.

“Every time astronomers point an object at the Webb, new and surprising discoveries can occur,” Dr. Faherty said.

“When we started this project, we weren't concerned about methane emissions, but now that we know that methane emissions can exist and the explanations are very attractive, we're always paying attention. That's part of how science moves forward.”

a paper The survey results were published in a magazine Nature.

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JK Faherty other. 2024. Methane emission from cool brown dwarfs. Nature 628, 511-514; doi: 10.1038/s41586-024-07190-w

Source: www.sci.news