Webb studies the intricate makeup of Jupiter’s ionosphere

Posted on June 26, 2024 by Igor Mitreski

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

Source: www.sci.news

Webb finds early universe protoglobular cluster

Posted on June 24, 2024 by Igor Mitreski

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

Source: www.sci.news

Webb uncovers puzzling alignment of protostellar outflows in the Ophiuchus Nebula

Posted on June 21, 2024 by Igor Mitreski

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.

Source: www.sci.news

Webb Reveals the Inner Workings of the Crab Nebula

Posted on June 19, 2024 by Igor Mitreski

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

Source: www.sci.news

Webb discovers massive collision in Beta Pictoris star system

Posted on June 12, 2024 by Igor Mitreski

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

Source: www.sci.news

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

Posted on June 7, 2024 by Igor Mitreski

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

Posted on June 1, 2024 by Igor Mitreski

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

Posted on May 30, 2024 by Igor Mitreski

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

Posted on April 30, 2024 by Igor Mitreski

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

Posted on April 18, 2024 by Igor Mitreski

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

Webb delves into the mysterious depths of Messier 82

Posted on April 4, 2024 by Igor Mitreski

Astronomers using the NASA/ESA/CSA James Webb Space Telescope discovered the central starburst of Messier 82 (M82, NGC 3034, or Cigar Galaxy), a starburst irregular galaxy 12 million light-years away in the constellation A new image of the area was taken. of Ursa Major.

Messier 82 was observed by the NASA/ESA Hubble Space Telescope in 2006, showing a spiral disk, shredded clouds, and hot hydrogen gas right next to the galaxy. The NASA/ESA/CSA James Webb Space Telescope observed the center of Messier 82, capturing the structure of the galactic wind in unprecedented detail and revealing the characteristics of individual stars and star clusters. Image credits: NASA / ESA / CSA / Hubble / Webb / STScI / A. Bolatto, UMD.

Messier 82 is located approximately 12 million light years away. It can be seen high in the northern sky in spring, in the direction of Ursa Major in the north.

First discovered by German astronomer Johann Erath Bode in 1774, this galaxy is approximately 40,000 light-years in diameter.

Messier 82 is also called the Cigar Galaxy because of its elongated elliptical shape caused by the tilt of its star-like disk with respect to our line of sight.

This galaxy is famous for its unusually high rate of new star formation, with stars being born 10 times faster than the Milky Way.

Astronomer Alberto Borat and his colleagues at the University of Maryland led Webb's research. NIRCam (Near Infrared Camera) We will aim our instrument at the center of Messier 82 to closely observe the physical conditions that promote the formation of new stars.

“Messier 82 is thought to be the prototype of a starburst galaxy and has attracted a variety of observations over the years,” Borat said.

“Both the Spitzer Space Telescope and the Hubble Space Telescope have observed this target. With Webb's size and resolution, we can observe this star-forming galaxy and see all of this beautiful new detail.”

“Star formation remains a mystery because it is shrouded by a curtain of dust and gas, which poses an obstacle to observing this process.”

“Fortunately, Webb's ability to see into the infrared can help us navigate these ambiguous situations.”

“Furthermore, these NIRCam images of the center of the starburst were obtained using instrumental mode, which prevents very bright light sources from overwhelming the detector.”

“Even in this infrared image, dark brown dust tendrils are visible throughout Messier 82's bright white core, but Webb's NIRCam has revealed a level of detail that was historically hidden.”

“If you look closely toward the center, small green specks indicate areas of concentrated iron, most of which are supernova remnants.”

“The small red spots indicate regions where hydrogen molecules are illuminated by radiation from nearby young stars.”

“This image shows the Webb's force,” said Dr. Rebecca Levy, an astronomer at the University of Arizona.

“All the white dots in this image are stars or star clusters. We can start to distinguish between all of these small point sources, which will allow us to get an accurate count of all the star clusters in this galaxy. Masu.”

If you look at Messier 82 at slightly longer infrared wavelengths, you'll see clumpy tendrils, shown in red, extending up and down the galactic plane. These gaseous streamers are galactic winds blowing out from the starburst's center.

One of the research team's areas of focus was understanding how this galactic wind, caused by rapid star formation and subsequent supernovae, originates and affects the surrounding environment.

By resolving Messier 82's central region, astronomers were able to investigate where the winds originate and gain insight into how hot and cold components interact in the wind. .

Webb's NIRCam instrument was well-suited to tracking the structure of the galactic wind via radiation from sooty chemical molecules known as polycyclic aromatic hydrocarbons (PAHs).

PAHs can be thought of as very small dust particles that survive at low temperatures but are destroyed at high temperatures.

Much to the team's surprise, Webb's observations about PAH emissions highlight previously unknown fine structures in the galactic wind.

This emission, depicted as a red filament, moves away from the central region where the center of star formation is located.

Another unexpected finding was the similarity between the structure of the PAH emission and the structure of the hot ionized gas.

“It was unexpected that the release of PAHs resembled ionized gases,” Dr. Borat said.

“PAHs are not thought to survive very long when exposed to such strong radiation fields, so they are probably constantly being replenished.”

“This casts doubt on our theory and indicates the need for further investigation.”

team's paper will be published in astrophysical journal.

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Alberto D. Borat other. 2024. Observation of starbursts by JWST: Emission of polycyclic aromatic hydrocarbons at the root of the M 82 galactic wind. APJ, in press. arXiv: 2401.16648

Source: www.sci.news

Webb discovers complex organic compounds in interstellar ice approaching dual protostars

Posted on March 15, 2024 by Igor Mitreski

astronomer using Mid-infrared measuring instrument The NASA/ESA/CSA James Webb Space Telescope's (MIRI) detected molecules ranging from relatively simple ones like methane to complex compounds like ethanol (alcohol) and acetic acid. interstellar ice One low-mass protostar and one high-mass protostar: toward NGC 1333 IRAS 2A and IRAS 23385+6053, respectively.

This image taken by Webb's MIRI instrument shows the region near the IRAS 23385+6053 protostar. Image credit: NASA/ESA/CSA/WRM Rocha, LEI.

Complex organic molecules (COM) are molecules with six or more atoms, including at least one carbon atom.

These materials are the raw material for future exoplanetary systems and are therefore of essential importance in understanding the chemical complexity developed in star-forming regions.

If this material becomes available in a primitive planetary system, it could facilitate the planet's habitability.

In a new study, astronomers Will Rocha, Harold Linnaerts and colleagues at Leiden University used Webb's mid-infrared instrument to determine the extent of COM ice in two protostars, NGC 1333 IRAS 2A and IRAS 23385+6053. We investigated the characteristics.

They were able to identify a variety of COMs, including ethanol (alcohol) and perhaps acetic acid (a component of vinegar).

“Our discovery contributes to one of the long-standing questions in astrochemistry,” Dr. Rocha said.

“What is the origin of COM in the Universe?” Are they created in the gas phase or in ice? Detection of COM in ice is based on the solid phase at the surface of cold dust particles It suggests that chemical reactions can build complex types of molecules. ”

“Some COMs, including those detected in the solid phase in our study, were previously detected in the warm gas phase, so they are now thought to originate from ice sublimation.”

“Sublimation is the change from a solid directly to a gas without becoming a liquid.”

“Therefore, we have hope that detecting COM in ice will improve our understanding of the origins of other, larger molecules in the universe.”

This figure shows the spectrum of the NGC 1333 IRAS 2A protostar. Image credit: NASA/ESA/CSA/Leah Hustak, STScI.

The researchers also detected simpler molecules such as formic acid, methane, formaldehyde, and sulfur dioxide.

“Sulfur-containing compounds, such as sulfur dioxide, played an important role in promoting metabolic reactions on early Earth,” the researchers said.

“Of particular interest is that one of the investigated origins, NGC 1333 IRAS 2A, is characterized as a low-mass protostar.”

“NGC 1333 IRAS 2A may resemble the early stages of our solar system.”

“Therefore, the chemicals identified around this protostar may have been present during the earliest stages of the development of the solar system and were later delivered to the proto-Earth.”

“All of these molecules could become part of comets, asteroids, and ultimately new planetary systems as icy material is transported inside planet-forming disks as protostar systems evolve.” '' said Dr. Ewain van Dyschoek, an astronomer at Leiden University.

“We look forward to using more web data in the coming years to follow this astrochemical trajectory step by step.”

of the team paper It was published in the magazine astronomy and astrophysics.

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WRM Rocha other. 2024. JWST Young Protostar Observation (JOYS+): Detection of icy complex organic molecules and ions. I.CH._FourSo₂,HCOO⁻,OCN⁻,H₂Colorado, Cooh, Switzerland₃CH₂Oh, CH₃Cho, channel₃Ocho and CH₃Coo. A&A 683, A124; doi: 10.1051/0004-6361/202348427

Source: www.sci.news

Webb observations provide new insights into the enigma of “Hubble tension”

Posted on March 13, 2024 by Igor Mitreski

When you’re trying to solve one of the biggest puzzles in cosmology, you need to triple-check your homework. The mystery, called the Hubble tension, is that the universe is currently expanding faster than astronomers expect based on the initial conditions of the universe and our current understanding of its evolution. Astronomers using the NASA/ESA Hubble Space Telescope and many other telescopes are constantly discovering numbers that don’t match predictions based on observations from ESA’s Planck mission. Does this discrepancy require new physics to resolve, or is it a result of measurement errors between the two different methods used to determine the rate of expansion of space?

NGC 5468 is an image of a galaxy located approximately 142 million light-years away in the constellation Virgo, combining data from Hubble and Webb. Image credit: NASA / ESA / CSA / STScI / A. Riess, JHU & STScI.

One of the scientific justifications for building Hubble was to use its observational capabilities to provide accurate values for the rate of expansion of the universe.

Before Hubble’s launch in 1990, ground-based telescope observations were subject to large uncertainties. Depending on what we infer from the expansion rate, the age of the universe could be between 10 and 20 billion years old.

Over the past 34 years, Hubble has reduced this measurement to less than 1% accuracy, dividing the difference by an age value of 13.8 billion years.

This was achieved by improving the so-called “cosmic distance ladder” by measuring important milepost markers known as Cepheid variable stars.

However, the Hubble value does not match other measurements that suggest the universe expanded faster after the Big Bang.

These observations were made by mapping the Cosmic Microwave Background (CMB) radiation by ESA’s Planck satellite.

A simple solution to this dilemma would be that the Hubble observations are wrong as a result of some inaccuracy creeping into the measurements of the deep space yardstick.

Then the James Webb Space Telescope came along, allowing astronomers to cross-check Hubble’s results.

Webb’s infrared observations of Cepheids were consistent with Hubble’s optical data.

Webb confirmed that Hubble’s keen observations were correct all along and dispelled any lingering doubts about Hubble’s measurements.

The bottom line is that the Hubble tension between what’s happening in the nearby universe and the expansion of the early universe remains a perplexing puzzle for cosmologists.

“There may be something woven into the fabric of the universe that we don’t yet understand,” the astronomers said.

“Do we need new physics to resolve this contradiction? Or is it the result of measurement errors between the two different methods used to determine the rate of expansion of space?”

Hubble and Webb are now working together to make the final measurements, making it even more likely that something else, not measurement error, is influencing the rate of expansion.

Dr. Adam Rees, a physicist at Johns Hopkins University and leader of the SH0ES (Dark Energy Equation of State Supernova “This is a very real and interesting possibility.” ) Team.

As a cross-check, the first Webb observations in 2023 confirmed that Hubble’s measurements of the expanding universe were accurate.

But in hopes of softening the Hubble tension, some scientists have speculated that invisible measurement errors may grow and become visible as we look deeper into the universe.

In particular, star crowding can systematically affect measurements of the brightness of more distant stars.

The SH0ES team obtained additional observations by Webb of an object that is a Cepheid variable star, an important cosmic milepost marker. This can now be correlated with Hubble data.

“We now have the entire range observed by Hubble and can rule out measurement errors as a cause of the Hubble tension with very high confidence,” Dr. Rees said.

The team’s first few Webb observations in 2023 succeeded in showing that Hubble is on the right track in firmly establishing the fidelity of the first rung of the so-called cosmic distance ladder.

Astronomers use different methods to measure relative distances in space, depending on the object they are observing.

These techniques are collectively known as the space distance ladder. Each stage or measurement technique relies on previous steps for calibration.

But some astronomers believe that the cosmic distance ladder could become unstable as we move outward along the second rung, as Cepheid measurements become less accurate with distance. suggested.

Such inaccuracies can occur because the Cepheid’s light can mix with the light of neighboring stars. This effect can become more pronounced at greater distances, as stars become denser in the sky and harder to distinguish from each other.

The observational challenge is that past Hubble images of these more distant Cepheid variable stars show that as the distance between us and our host galaxy grows ever greater, they appear to overlap more closely with their neighbors. Therefore, this effect needs to be carefully considered.

Intervening dust makes reliable measurements in visible light even more difficult.

The web cuts through the dust, naturally isolating the Cepheid cluster from its neighboring stars. The reason is that its view is clearer at infrared wavelengths than the Hubble Cluster.

“Combining Webb and Hubble gives us the best of both worlds. We find that the reliability of Hubble measurements remains as we climb further along the cosmic distance ladder,” Dr. Rees said.

The new Webb observations include five host galaxies consisting of eight type Ia supernovae containing a total of 1,000 Cepheids, and are located 130 million light-years away, the most distant galaxy in which Cepheids have been sufficiently measured. NGC 5468 is also reached in the distance.

“This spans the entire range measured by Hubble, so we’ve reached the end of the second rung of the cosmic distance ladder,” said Dr. Gagandeep Anand, an astronomer at the Space Telescope Science Institute. Told.

of the team paper Published in Astrophysics Journal Letter.

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Adam G. Reese other. 2024. JWST observations refute unrecognized crowding of Cepheid photometry as an explanation for the Hubble tension with 8σ confidence. APJL 962, L17; doi: 10.3847/2041-8213/ad1ddd

Source: www.sci.news

Webb discovers unique helium cloud surrounding GN-z11 in its Halo

Posted on March 6, 2024 by Igor Mitreski

GN-z11 is an extremely bright galaxy that existed just 420 million years ago, making it one of the oldest and most distant galaxies ever observed.

This two-part diagram shows evidence of a gaseous mass of helium in the halo surrounding galaxy GN-z11. The small box at the top right corner shows her GN-z11 in the galaxy. The box in the center shows a magnified image of the galaxy. The left-most box shows a map of helium gas in GN-z11's halo. This also includes clumps that are not visible in the infrared colors shown in the center panel. The spectrum in the bottom half of the graphic shows a distinct “fingerprint” of helium within the halo. The full spectrum shows no evidence of other elements, so the helium blob must be fairly pure, made from leftover hydrogen and helium gas from the Big Bang, with little contamination from heavier elements produced by stars. It suggests that there is no. Theory and simulations near particularly massive galaxies of these epochs predict that pockets of primordial gas must remain within the halo, and that these may collapse to form Population III clusters. doing. Image credit: NASA/ESA/CSA/Ralf Crawford, STScI.

GN-z11 is an early but moderately massive galaxy located in the constellation Ursa Major.

First discovered by the NASA/ESA Hubble Space Telescope in 2016, the galaxy is estimated to be just 420 million years old, or 3% of its current age.

GN-z11 is about 25 times smaller than the Milky Way, with only 1% of the mass of stars in our galaxy.

Remarkably, this galaxy is home to a supermassive black hole of approximately 1.6 million solar masses that is rapidly accreting matter.

using, near infrared spectrometer Astronomer Roberto Maiorino of the University of Cambridge and colleagues detected gaseous clumps of helium in the halo surrounding GN-z11 using the NASA/ESA/CSA James Webb Space Telescope's (NIRSpec) instrument.

“The fact that we don't see anything but helium suggests that this mass must be fairly pure,” Maiorino said.

“This is what was predicted by theory and simulations near particularly massive galaxies of these times. There should be pockets of primordial gas left in the halo, and these collapse into population III. They may form star clusters.”

Finding never-before-seen “Population III stars” (first generation stars formed almost entirely of hydrogen and helium) is one of the most important goals of modern astrophysics.

These stars are expected to be very massive, very bright, and very hot.

Their expected characteristics are the presence of ionized helium and the absence of chemical elements heavier than helium.

The formation of the first stars and galaxies marked a fundamental change in the history of the universe, during which the universe went from a dark and relatively simple state to the highly structured and complex state we see today. It has evolved into an environment.

“In future Webb observations, we hope to probe GN-z11 more deeply and strengthen our case for Population III stars potentially forming within the halo,” the astronomers said.

The survey results are journal astronomy and astrophysics.

Source: www.sci.news

Webb unveils stunning new images of NGC 1559

Posted on February 29, 2024 by Igor Mitreski

NASA/ESA/CSA’s James Webb Space Telescope has captured new images of barred spiral galaxy NGC 1559.

This Webb image shows barred spiral galaxy NGC 1559, located approximately 32 million light-years away in the constellation Reticulata. Image credits: NASA / ESA / CSA / Webb / A. Leroy / J. Lee / PHANGS Team.

NGC 1559 is situated about 32 million light-years away in the southern constellation Rechi.

Also known as LEDA 14814, ESO 84-10, and IRAS 04170-6253, this galaxy was first observed in 1826 by Scottish astronomer James Dunlop.

NGC 1559 features extensive spiral arms filled with star formation and is receding from us at a speed of approximately 1,300 km/s.

It has a mass of around 10 billion solar masses, which may seem substantial, but it’s almost 100 times less than the mass of our Milky Way galaxy.

“NGC 1559 exhibits a massive spiral arm of active star formation moving away from us at 1,300 kilometers per second,” explained the Webb astronomers.

“Although NGC 1559 appears to be close to the Large Magellanic Cloud, one of the nearest clouds in the sky, this is merely a perspective illusion.”

“In reality, NGC 1559 is not physically near the Large Magellanic Cloud in space. It is actually isolated, lacking any nearby galactic companions or members of galaxy clusters.”

Images of NGC 1559 are composed of data from Webb’s two instruments: Mid-infrared measuring instrument (Miri) and near infrared camera (NIRCam).

“MIRI captures the glow of interstellar dust particles that trace the interstellar medium fueling future star formation,” the astronomers elaborated.

“NIRCam reflects starlight and reveals young stars hidden behind vast amounts of dust.”

“This instrument also detects emission from ionizing nebulae around young stars.”

The image of NGC 1559 was taken by the PHANGS team as part of Webb’s observation of 55 galaxies using instruments such as the Atacama Large Millimeter/Submillimeter Array (ALMA) and the NASA/ESA Hubble Space Telescope.

“By combining Webb’s unique view of dust and stars with data from these other facilities, we can delve into the detailed processes of star birth, life, and death in galaxies across the universe. Our goal is to gain new insights into this phenomenon,” stated the researchers.

“This program is also part of a Treasury Department initiative, allowing immediate access to the data for the scientific community and the general public,” they added.

“This enables us to conduct more research at a faster pace.”

Source: www.sci.news

Webb uncovers incredible black hole in the ancient cosmos

Posted on February 28, 2024 by Igor Mitreski

Using the NASA/ESA/CSA James Webb Space Telescope, astronomers observed a very red quasar-like object. A2744-QSO1 Its color suggests that A2744-QSO1's black hole lies behind a thick veil of dust obscuring much of its light. The researchers also measured the black hole's mass (40 million solar masses) and found it to be much more massive compared to its host galaxy than what has been seen in more localized examples. . This discovery suggests that it may represent the missing link between black hole seeds and the first luminescent quasars.

A composite color image of A2744-QSO1. Image credit: Furutaku other, doi: 10.1038/s41586-024-07184-8.

“We were very excited when Webb started transmitting its first data,” said Dr. Lukas Furtak, a postdoctoral researcher at Ben-Gurion University of the Negev.

“As we were scanning the data coming in for the UNCOVER program, three very compact objects with red flowers stood out to us.”

“Because of its 'red dot' appearance, we immediately suspected it to be a quasar-like object.”

“Using a numerical lensing model we built for the Abell 2744 galaxy cluster, we found that the three red dots are multiples of the same background light source seen when the universe was just 700 million years old. “We determined that it must be an image of Adi Zitlin, also from Ben-Gurion University in the Negev.

“Analysis of the object's color shows that it is not a typical star-forming galaxy,” said Professor Rachel Bezanson, an astronomer at the University of Pittsburgh.

“This further supports the supermassive black hole hypothesis.”

“Together with its compact size, it became clear that this was probably a supermassive black hole, but it was still different from other quasars discovered earlier.”

The astronomers then analyzed the JWST/NIRSpec spectrum of A2744-QSO1.

“The spectrum was just shocking,” said Professor Ivo Rabe of Swinburne University of Technology.

“The spectrum obtained by combining the signals from the three images and the lens magnification corresponds to 1,700 hours that Webb observed the object without a lens, making it the deepest spectrum Webb obtained for a single object in the early universe. Masu.”

“Using the spectrum, we were able to not only confirm that this red compact object is a supermassive black hole and measure its precise redshift, but also estimate its mass based on the width of its emission line. We were able to get a solid estimate,” Dr. Furtak said.

“The gas orbits the black hole's gravitational field, achieving extremely high velocities not seen in other parts of the galaxy.”

“Due to the Doppler shift, the light emitted from the accreting material is redshifted on one side and blueshifted on the other side, depending on its velocity.”

“This makes the emission lines in the spectrum wider.”

But this measurement brought yet another surprise. The black hole's mass appears to be disproportionately large compared to the mass of its host galaxy.

“All the light in that galaxy would have to fit within a small region about the size of a modern star cluster,” said Dr. Jenny Green, an astronomer at Princeton University.

“The source's gravitational lensing magnification provided an exquisite constraint on size.”

“Even if you pack all possible stars into such a small region, the black hole will end up being at least 1% of the total mass of the system.”

“In fact, it has now been discovered that several other supermassive black holes in the early Universe exhibit similar behavior, which provides insight into the growth of black holes and host galaxies, and the interactions between them. This provides some interesting insights, but this is not well understood.”

Astronomers do not know whether such supermassive black holes grow from the remains of stars, for example, or perhaps from material that collapsed directly into black holes in the early universe.

“In some ways, this is an astrophysical chicken-and-egg problem,” says Professor Zitlin.

“Currently we don't know whether galaxies or black holes formed first, how big the first black holes were, and how they grew.”

“Recently, many more such 'little red dots' and other active galactic nuclei have been detected in the Webb, so we hope to have a better idea soon.”

of the team result appear in the diary Nature.

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LJ Furutak other. High black hole-to-host mass ratio in the lensed AGN of the early Universe. Nature, published online on February 14, 2024. doi: 10.1038/s41586-024-07184-8

Source: www.sci.news

Webb Observatory detects radiation from the neutron star remnant of supernova 1987A

Posted on February 24, 2024 by Igor Mitreski

SN 1987A is the only supernova visible to the naked eye in the past 400 years and the most studied supernova in history. This event was a nuclear collapse supernova, meaning that the compressed remains of its core formed either a neutron star or a black hole. Evidence for such compact objects has long been sought, and while indirect evidence for the existence of neutron stars has been found before, most likely the effects of high-energy emissions from young neutron stars have not been detected. This is the first time I have done so.

Webb observed the best evidence to date for radiation from neutron stars in SN 1987A. Image credits: NASA / ESA / CSA / STScI / C. Fransson, Stockholm University / M. Matsuura, Cardiff University / MJ Barlow, University College London / PJ Kavanagh, Maynooth University / J. Larsson, KTH Royal Institute of Technology.

SN 1987A was first observed on February 23, 1987 at the edge of the Large Magellanic Cloud, about 163,000 light-years away.

This was the first supernova to be observed with the naked eye since Johannes Kepler witnessed one more than 400 years ago.

About two hours before the first visible light observation of SN 1987A, three observatories around the world detected a burst of neutrinos that lasted just a few seconds.

The two different types of observations were associated with the same supernova event and provided important evidence that informs theories about how nuclear collapse supernovae occur.

This theory included the expectation that supernovae of this type would form neutron stars or black holes.

Since then, astronomers have been searching for evidence of these compact objects at the center of expanding debris.

Indirect evidence for the presence of neutron stars at the center of remnants has been discovered in recent years, with observations of much older supernova remnants such as the Crab Nebula showing that neutron stars have been found in many supernova remnants. has been confirmed.

However, until now no direct evidence of neutron star formation in the aftermath of SN 1987A has been observed.

“Theoretical models of SN 1987A suggest that the 10-second burst of neutrinos observed just before the supernova explosion led to the formation of a neutron star or black hole,” said lead author of the study. said Claes Fransson, an astronomer at Stockholm University.

“However, no convincing signs of such a newborn object due to a supernova explosion have been observed.”

“With this observatory, we found direct evidence of ejection caused by a newborn compact object, likely a neutron star.”

In the study, Dr. Franson et al. mm and NIR spec Instruments on NASA/ESA/CSA's James Webb Space Telescope observed SN 1987A at infrared wavelengths, showing that a heavy mass whose outer electrons have been stripped (i.e., atoms have become ionized) near where the star exploded occurred. They found evidence of argon and sulfur atoms. .

They modeled a variety of scenarios in which these atoms could be driven solely by ultraviolet or They discovered that it could have been ionized only by the wind. (Pulsar wind nebula).

If the former scenario were true, the neutron star's surface would be about 1 million degrees Celsius, cooling from about 100 billion degrees Celsius at the moment it formed at its collapse center more than 30 years ago.

Professor Mike Barlow of University College London said: “The detection of strong ionizing argon and sulfur emission lines from the very center of the nebula surrounding SN1987A using Webb's MIRI and NIRSpec spectrometers suggests a central source of ionizing radiation. This is direct evidence of the existence of .

“Our data can only match neutron stars as the power source of ionizing radiation.”

“This radiation is not only emitted from the multi-million-degree surface of a hot neutron star, but also from the pulsar winds that may be produced when a neutron star spins rapidly, dragging charged particles around it. It can also be emitted from nebulae.”

“The mystery surrounding whether neutron stars are hidden in dust has been going on for more than 30 years, so we are very happy to have solved it.”

“Supernovae are the main source of the chemical elements that make life possible, so we want to accurately derive the supernova model.”

“No other object like the neutron star SN 1987A is so close to us and formed so recently. The surrounding material is expanding, so we'll see more of it over time. It will be.”

“It was clear that there had to be a high-energy radiation source at the center of the SN 1987A debris to produce the ions observed in the ejecta,” Dr. Franson said.

“The paper discusses a variety of possibilities, but we found that only a few scenarios are likely, and all of them involve newly formed neutron stars.”

of paper Published in the February 22, 2024 edition of the Journal science.

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C. Franson other. 2024. Emission lines from ionizing radiation from a compact object in the remains of supernova 1987A. science 383 (6685): 898-903; doi: 10.1126/science.adj5796

Source: www.sci.news

Webb uncovers massive inactive galaxy with mature stars in the ancient cosmos

Posted on February 17, 2024 by Igor Mitreski

The formation of galaxies through the stepwise hierarchical coassembly of baryons and cold dark matter halos is a fundamental paradigm underpinning modern astrophysics and predicts a significant decline in the number of giant galaxies in the early Universe. . Very massive quiescent galaxies have been observed 1 to 2 billion years after the Big Bang. These form between 300 million and 500 million years ago and are very limiting for theoretical models, as only some models can form massive galaxies this early. The spectrum of newly discovered quiescent galaxy ZF-UDS-7329 reveals features typical of much older stellar populations. Detailed modeling shows that the stellar population formed about 1.5 billion years ago, when dark matter halos with sufficient host mass had not yet assembled in the standard scenario. This observation may indicate the existence of an undetected early population of galaxies and potentially large gaps in our understanding of the nature of early stellar populations, galaxy formation, and/or dark matter.

This web image shows ZF-UDS-7329, a rare massive galaxy that formed very early in the universe. Image credit: Glazebrook other., doi: 10.1038/s41586-024-07191-9.

Galaxy formation is a fundamental paradigm underpinning modern astrophysics, and a significant decrease in the number of massive galaxies in the early universe is predicted.

Very large quiescent galaxies have been observed 1 to 2 billion years after the Big Bang, casting doubt on previous theoretical models.

Professor Carl Glazebrook, from Swinburne University of Technology, said: “We have been tracking this galaxy for seven years, observing it for hours with two of the largest telescopes on Earth to find out its age.” Ta.

“But it was too red and too faint to be measured. In the end, we had to go outside Earth and use the web to see its properties.”

“This was truly a team effort, from the infrared sky survey that began in 2010 to identifying this galaxy as an anomaly, and the many hours spent with the Keck Telescope and the Very Large Telescope. But we couldn’t confirm it, and finally, last year, we spent a lot of effort trying to figure out how to process the web data and analyze this spectrum.”

“We are now beyond the realm of possibility to have identified the oldest giant stationary monster deep in the universe,” said Dr Temmiya Nanayakkara, an astronomer at Swinburne University of Technology.

“This pushes the limits of our current understanding of how galaxies form and evolve.”

“The key question now is how do stars form so quickly, so early in the universe, and how do they form at a time when other parts of the universe are forming stars? “What kind of mysterious mechanism could cause it to suddenly stop forming?”

“Galaxy formation is determined primarily by how dark matter is concentrated.”

“The presence of these extremely massive galaxies in the early universe poses significant challenges to our standard model of cosmology.”

“This is because dark matter structures large enough to accommodate these massive galaxies are unlikely to have formed yet.”

“More observations are needed to help us understand how common these galaxies are and how massive they really are.”

“This could open new doors in our understanding of the physics of dark matter,” Professor Glazebrook said.

“Webb continues to discover evidence that massive galaxies form early.”

“This result sets a new record for this phenomenon. It’s very impressive, but it’s just one object. But we want to discover more. If I If we were to do this, it would seriously disrupt our understanding of galaxy formation.”

This finding is reported in the following article: paper Published in this week’s magazine Nature.

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K. Glazebrook other. A huge galaxy that formed stars at z ~ 11. Nature, published online on February 14, 2024. doi: 10.1038/s41586-024-07191-9

Source: www.sci.news

Webb discovers evidence of hydrothermal activity within Ellis and Makemake

Posted on February 16, 2024 by Igor Mitreski

Methane ice of unknown origin exists on the surfaces of the icy dwarf planets Eris and Makemake. Analysis of data from the NASA/ESA/CSA James Webb Space Telescope shows that Ellis and Makemake have rocky cores that have undergone significant radiation heating and are still hot/hot enough to produce methane. There is a possibility.

grain other. Researchers have discovered evidence of hydrothermal or metamorphic activity deep within the icy dwarf planets Eris and Makemake. Image courtesy of Southwest Research Institute.

“We're seeing some interesting signs of a hot period in a cool place,” said Dr. Christopher Grein, a planetary researcher at the Southwest Research Institute.

“I approached this project thinking that because the cold surfaces of large Kuiper Belt Objects (KBOs) can store volatile materials like methane, they should have ancient surfaces with material inherited from the proto-solar nebula. I participated.”

“Instead, Webb had a surprise for us! We found evidence of a thermal process producing methane from inside Ellis and Makemake.”

Dr. Grein and his colleagues used the Webb to observe isotope molecules on the surfaces of Ellis and Makemake for the first time.

These so-called isotopologues are molecules containing atoms with different numbers of neutrons. These provide data that helps us understand the evolution of planets.

The astronomers measured the composition of the dwarf planet's surface, specifically the ratio of deuterium (deuterium, D) to hydrogen (H) in methane.

Deuterium is thought to have formed in the Big Bang, and hydrogen is the most abundant atomic nucleus in the universe.

The D/H ratio of planetary bodies provides information about the origin, geological history, and formation routes of hydrogen-containing compounds.

“The moderate D/H ratio observed by Mr. Webb discredits the existence of primordial methane on the ancient Earth's surface. The D/H ratio of primordial methane would be much higher,” Dr. Grein said. I did.

“Instead, the D/H ratio indicates the geochemical origin of the methane produced deep inside. The D/H ratio is like a window. You can use it to look into the subsurface.”

“Our data suggest that temperatures in the cores of these world rocks could increase and methane could be cooked.”

“Nitrogen molecule (N₂) may be generated as well, and this has also been confirmed in Eris. ”

“Hot cores may also indicate a potential source of liquid water beneath the surface of the ice.”

“If Eris and Makemake harbored, or perhaps still harbor, warm or hot geochemistry in their rocky cores, then the surface of these planets is probably geologically recent, due to cryogenic volcanic activity. could be supplied with methane,” said Dr. Will Grundy. Astronomer at Lowell Observatory.

“We discovered the carbon isotope ratio (¹³C/¹²C) suggests that the surface has been resurfaced relatively recently. ”

“Following NASA's New Horizons flyby of the Pluto system, and with this discovery, the Kuiper Belt turns out to be much more alive than we imagined in terms of hosting a dynamic world.” said Dr. Grein.

“It's not too early to start thinking about sending spacecraft to fly close to other of these objects to put Webb's data into geological context. I'm sure we'll see the surprises that lie ahead. I think you’ll be surprised!”

of study It was published in the magazine Icarus.

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Christopher R. Grein other. 2024. Moderate D/H ratios in the Ellis and Makemake methane ices indicate evidence of hydrothermal or metamorphic processes in the interior: a geochemical analysis. Icarus 412: 115999; doi: 10.1016/j.icarus.2024.115999

Source: www.sci.news

New discoveries from the Webb telescope shed light on the origins of supermassive black holes and galaxies

Posted on February 7, 2024 by Igor Mitreski

New insights from the NASA/ESA/CSA James Webb Space Telescope overturn theories about how black holes shape the universe, reversing the classical theory that black holes formed after the first stars and galaxies appeared. It challenges our understanding. In fact, black holes may have accelerated the birth of new stars during the universe's first 50 million years.

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.

“We know that these monster black holes exist in the centers of galaxies near the Milky Way, but now the big surprise is that they were also present at the beginning of the universe, and that they were like building blocks or seeds of early galaxies. It was something,” he said. Professor Joseph Silk, an astronomer at Johns Hopkins University and the Sorbonne Institute of Astrophysics;

“They've really enhanced everything, including giant amplifiers for star formation. This completely overturns what we previously thought was possible, and how galaxies form. It has the potential to completely shake up our understanding of what happens.”

“The distant galaxies observed by Webb in the early universe appear much brighter than scientists expected, revealing an unusually large number of young stars and supermassive black holes.”

“Conventional wisdom holds that black holes formed after the collapse of supermassive stars, and that galaxies formed after the first stars illuminated the dark early universe.”

But the team's analysis suggests that for the first 100 million years, black holes and galaxies coexisted, influencing each other's fate.

“We argue that the outflow of the black hole crushed the gas clouds and turned them into stars, greatly accelerating the rate of star formation,” Professor Silk said.

“Otherwise, it's very difficult to understand where these bright galaxies came from, because they are typically smaller in the early Universe. Why on earth did they become stars so quickly? Do I need to create one?”

“A black hole is a region of space where gravity is so strong that not even light can escape its attraction.”

“Thanks to this force, they generate powerful magnetic fields that cause violent storms, eject turbulent plasma, and ultimately act like giant particle accelerators.”

“This process may be why Webb's detectors found more black holes and brighter galaxies than scientists expected.”

“We can't fully see these ferocious winds and jets so far away, but we know they must exist because many black holes have been seen in the early universe. I am.”

“The huge wind blowing from the black hole crushes nearby gas clouds, turning them into stars.”

“This is the missing link that explains why these first galaxies are much brighter than we expected.”

According to the research team, there were two stages of the young universe.

In the first stage, star formation was accelerated by high-velocity outflow from the black hole, while in the second stage, the outflow slowed down.

“Hundreds of millions of years after the Big Bang, a supermassive black hole magnetic storm caused gas clouds to collapse and new stars to form at a rate far exceeding that observed in normal galaxies billions of years later,” Professor Silk said. Ta.

“These powerful outflows moved into energy conservation states, reducing the amount of gas available to form stars within the galaxy, thus slowing star formation.”

“We originally thought that galaxies formed when giant gas clouds collapsed,” Professor Silk said.

“The big surprise was that there was a seed in the middle of that cloud, a large black hole, that helped rapidly turn the inside of that cloud into a star at a much faster rate than we expected. So the first galaxies are incredibly bright.”

of study Published in Astrophysics Journal Letter.

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joseph silk other. 2024. Which came first, a supermassive black hole or a galaxy? Insights from JWST. APJL 961, L39; doi: 10.3847/2041-8213/ad1bf0

Source: www.sci.news

Oldest black hole detected by Webb

Posted on January 19, 2024 by Igor Mitreski

NASA/ESA/CSA Astronomers using the James Webb Space Telescope have discovered a small, active galaxy within GN-z11, an extremely bright galaxy that existed just 420 million years after the Big Bang, more than 13 billion years ago. detected a black hole. The existence of this multi-million solar mass black hole in the early universe challenges current assumptions about how black holes form and grow.

GN-z11, shown in the inset, was 13.4 billion years ago, just 400 million years after the Big Bang. Image credits: NASA / ESA / P. Oesch, Yale University / G. Brammer, STScI / P. van Dokkum, Yale University / G. Illingworth, University of California, Santa Cruz.

Astronomers believe that supermassive black holes found at the centers of galaxies like the Milky Way have grown to their current size over billions of years.

But the size of this newly discovered black hole suggests that black holes may form in another way. That means black holes could be “born big,” or eat matter five times faster than previously thought.

According to the Standard Model, supermassive black holes form from the remains of dead stars, which can collapse to form black holes about 100 times the mass of the Sun.

If this newly detected black hole grows as expected, it will take about a billion years to grow to its observed size.

However, when this black hole was detected, the universe was less than 1 billion years old.

Dr Roberto Maiolino, an astronomer at the University of Cambridge, said: “Since the last time such a massive black hole has been observed was in the very early days of the universe, we need to consider other ways in which black holes could form.'' Ta.

“Very early galaxies were so rich in gas that they would have been a buffet for black holes.”

Like all black holes, GN-z11's young black hole is accreting matter from its host galaxy to fuel its growth.

But it turns out that this ancient black hole gulped down matter much more energetically than its later cousins.

GN-z11 is a compact galaxy, about 100 times smaller than the Milky Way, but a black hole may be having a negative impact on its development.

When a black hole consumes too much gas, it pushes it away like a super-fast wind.

This “wind” could stop the star formation process and slowly kill the galaxy, but it would also kill the black hole itself, because it would also cut off its source of “food.”

“This is a new era. The huge leap in sensitivity, especially in the infrared, is like upgrading from Galileo's telescope to a modern telescope overnight,” Dr. Maiorino said.

“Before Mr. Webb came online, I thought the universe beyond what the NASA/ESA Hubble Space Telescope could see might not be all that interesting.”

“But that wasn't the case at all. The universe is very generous with what it shows us, and this is just the beginning.”

“Webb's sensitivity means that even older black holes may be discovered in the coming months or years,” he added.

“We hope to use Webb's future observations to find smaller 'seeds' of black holes. We hope to find out the different ways in which black holes form – do they start out large? “It may help us understand the different ways black holes can form, such as whether they grow rapidly or whether they grow quickly.”

a paper The survey results were published in a magazine Nature.

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R. Maiolino other. A small, active black hole that existed in the early universe. Nature, published online on January 17, 2023. doi: 10.1038/s41586-024-07052-5

Source: www.sci.news

New Observations by Webb Show Significant Conflict in Beta Pictoris

Posted on January 11, 2024 by Igor Mitreski

Dr. Christopher Stark and colleagues at NASA Goddard Space Flight Center present new coronagraphic images from Earth NIRCam (near infrared camera) and mm (Mid-Infrared Instrument) instruments aboard the NASA/ESA/CSA James Webb Space Telescope reveal never-before-seen structures in the debris disk around the young star Beta Pictoris.

Pictoris Beta is a young planetary system located approximately 63 light-years from Earth.

Estimated to be only 20 million years old, it is known to be home to the gas giant Beta Pictoris b.

In the new study, Stark and co-authors used Webb's NIRCam and MIRI instruments to investigate the composition of Beta Pictoris' primary and secondary debris disks.

“Pictoris Beta is an all-inclusive debris disk. It has a very bright and close star that we can study well, a multicomponent disk, an exocomet, and two imaged “There is a complex circumstellar environment that includes exoplanets,” the Astrobiology Center said. astronomer Isabel Rebolido;

“There have been ground-based observations in this wavelength range before, but this feature was not detected because we did not have the sensitivity and spatial resolution of the current web.”

Even with Webb, peering into Beta Pictoris in the right wavelength range was crucial to detecting the never-before-seen dust trail, which resembles a cat's tail. This is because it only appeared in MIRI data.

Webb's mid-infrared data also revealed differences in temperature between Beta Pictoris' two disks. This is probably due to differences in composition.

“We didn't expect Webb to reveal that there are two different types of material surrounding Beta Pictoris, but MIRI clearly shows that the material in the secondary disk and cat's tail is hotter than the main disk. Dr. Stark said.

“The dust that forms its disk and tail must be so dark that it is not easily visible at visible wavelengths, but it glows in the mid-infrared.”

This artist's impression shows an exocomet orbiting the star Pictoris Beta. Image credit: L. Calçada / ESO.

To explain the higher temperatures, astronomers speculated that the dust could be a porous “organic refractory” similar to the material found on the surfaces of comets and asteroids in our solar system. .

For example, preliminary analysis of material collected from the asteroid Bennu by NASA's OSIRIS-REx mission revealed very dark, carbon-rich material similar to what MIRI detected on Beta Pictoris.

But big questions still remain. What explains the shape of the cat's tail, a uniquely curved feature unlike those seen in disks around other stars?

Researchers modeled various scenarios to mimic a cat's tail and uncover its origins.

Although more research and experiments are needed, the researchers offer a strong hypothesis that cat tails are the result of a dust-producing phenomenon that occurred just 100 years ago.

“Something happens, like a collision, and it creates a lot of dust,” says Dr. Marshall Perrin, an astronomer at the Space Telescope Science Institute.

“At first, the dust follows the same trajectory as its source, but then it starts to spread out.”

“Light from the star pushes the smallest, fluffiest dust particles away from the star faster, while larger particles move less, creating long dust tendrils.”

“The characteristics of a cat's tail are so unusual that it has been difficult to reproduce the curvature in mechanical models,” Dr. Stark said.

“Our model requires dust to be pushed out of the system very quickly, which also suggests it is made of organic refractory materials.”

“The model we have recommended explains the sharp angle of the tail away from the disk as a simple optical illusion.”

“Our perspective, combined with the curved shape of the tail, creates the observed tail angle, but in reality, the arc of material is only pointing away from the disk at a 5-degree inclination.”

“Considering the brightness of the tail, we estimate that the amount of dust in the cat's tail is equivalent to a large main-belt asteroid spanning 10 billion miles.”

Recent dust production events within Beta Pictoris' debris disk may also explain the newly observed asymmetric spreading of the tilted inner disk, shown in the MIRI data and only seen on the opposite side of the tail. there is.

“Our study suggests that Beta pictris may be even more active and chaotic than previously thought,” Dr. Stark said.

“The Webb continues to amaze us even when looking at the most well-studied celestial objects. We have a whole new window into these planetary systems.”

of result This week, it was announced in AAS243243rd Meeting of the American Astronomical Society, New Orleans, USA.

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christopher stark other. 2024. A new view of JWST's Beta Pictris suggests recent bursts of dust production from an eccentric, tilted secondary debris disk. AAS243Abstract #4036

Source: www.sci.news

Webb observes auroras on cold brown dwarf star

Posted on January 10, 2024 by Igor Mitreski

Using NASA/ESA/CSA’s James Webb Space Telescope, astronomers detected a brown dwarf with infrared emissions from methane, likely due to energy in the upper atmosphere. The heating of the upper atmosphere that drives this emission is associated with auroras. The brown dwarf, named W1935, is located 47 light-years away.

Artist’s impression of the brown dwarf W1935. Image credit: NASA/ESA/CSA/L. Hustak, STScI.

On Earth, auroras occur when energetic particles blasted into space from the sun are captured by Earth’s magnetic field.

They cascade into the atmosphere along magnetic field lines near the Earth’s poles, colliding with gas molecules and creating eerie, dancing curtains of light.

Jupiter and Saturn have similar auroral processes that involve interaction with the solar wind, but also receive auroral contributions from nearby active moons, such as Io (for Jupiter) and Enceladus (for Saturn). Masu.

“For an isolated brown dwarf like W1935, the absence of a stellar wind that contributes to auroral processes and accounts for the extra energy in the upper atmosphere required for methane emission is puzzling,” American Airlines astronomers said. said Dr. Jackie Faherty. Natural History Museum and colleagues.

Faherty and his colleagues used Webb to observe a sample of 12 cool brown dwarf stars.

These included object W1935, discovered by citizen scientist Dan Caselden who collaborated on the Backyard Worlds Zooniverse project, and object W2220, discovered using NASA’s Wide Field Infrared Survey Explorer.

Webb revealed in great detail that W1935 and W2220 appear to be close clones of each other in composition.

Also, the brightness, temperature, and spectral characteristics of water, ammonia, carbon monoxide, and carbon dioxide were similar.

A notable exception is that W1935 showed emission from methane, in contrast to the expected absorption feature observed for W2220. This was observed at infrared wavelengths, to which Webb is uniquely sensitive.

“We expected methane to be present because it’s everywhere in these brown dwarfs,” Faherty said.

“But instead of absorbing light, we found just the opposite. The methane was glowing. My first thought was, what the hell? Why is this object emitting methane?” Do you want it?

Astronomers used computer models to deduce what might be behind the emission.

Modeling work showed that W2220 has a predictable energy distribution in its atmosphere, becoming colder with increasing altitude.

On the other hand, W1935 produced surprising results. The best models supported a temperature inversion, where the atmosphere becomes warmer as altitude increases.

“This temperature inversion is really puzzling,” says Dr. Ben Burningham, an astronomer at the University of Hertfordshire.

“We’ve seen this kind of phenomenon on planets with nearby stars that can heat the stratosphere, but it’s outrageous to see something like this on a celestial body with no obvious external heat source. .

In search of clues, researchers looked to our backyard: the planets of our solar system.

The gas giant planet could serve as a proxy for what is seen happening 47 light-years away in the atmosphere of 1935 AD.

Scientists have noticed that planets like Jupiter and Saturn have significant temperature inversions.

Research is still ongoing to understand the causes of stratospheric heating, but leading theories about the solar system include external heating by auroras and internal energy transport from deep in the atmosphere, with the former being the leading explanation. ).

According to the research team, W1935 is the first aurora candidate outside the solar system with the signature of methane emission.

It is also the coldest aurora candidate outside the solar system, with an effective temperature of about 200 degrees Celsius (400 degrees Fahrenheit).

In our solar system, the solar wind is the main contributor to the auroral process, and active satellites like Io and Enceladus play the role of planets like Jupiter and Saturn, respectively.

W1935 does not have any companion stars, so stellar winds cannot contribute to this phenomenon. It is not yet known whether an active moon is responsible for her W1935's methane emissions.

“W1935 provides a spectacular expansion of solar system phenomena without any explanatory stellar illumination,” Faherty said.

“With Webb, we can actually ‘lift the lid’ on chemistry and figure out how auroral processes are similar or different outside of our solar system.”

The authors announced that findings this week’s AAS243243rd Meeting of the American Astronomical Society, New Orleans, USA.

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Jacqueline Faherty other. 2024. JWST exhibits the auroral features of frigid brown dwarfs. AAS243Abstract #4359

Source: www.sci.news

Webb finds small, free-floating brown dwarf in star-forming cluster IC 348

Posted on December 18, 2023 by Igor Mitreski

The newly discovered brown dwarf is estimated to have a mass three to four times that of Jupiter, making it a strong candidate for the lowest mass free-floating brown dwarf ever directly imaged.

This image from Webb’s NIRCam instrument shows the central portion of star cluster IC 348. Image credits: NASA / ESA / CSA / STScI / K. Luhman, Pennsylvania State University / C. Alves de Oliveira, ESA.

Brown dwarfs are cold, dark objects that are between the size of gas giant planets and Sun-like stars.

These objects, also known as failed stars, have star-like properties even though they are too small to sustain hydrogen fusion reactions in their cores.

Typically, their masses are between 11 and 16 Jupiter (the approximate mass that can sustain deuterium fusion) and 75 and 80 Jupiter (the approximate mass that can sustain hydrogen fusion).

“One of the basic questions you’ll find in any astronomy textbook is: What is the smallest star? That’s what we’re trying to answer,” said Kevin, an astronomer at Penn State University.・Dr. Luman said.

The newly discovered brown dwarf resides in IC 348, a star cluster 1,000 light-years away in the constellation Perseus.

The cluster, also known as Collinder 41, Gingrich 1, and Theia 17, contains nearly 400 stars and is about 5 million years old.

IC 348 is part of the larger Perseus star-forming region, and although it is normally invisible to the naked eye, it shines brightly when viewed at infrared wavelengths.

Dr. Luhmann and his colleagues used the following method to image the center of the star cluster. Webb’s NIRCam device Identify brown dwarf candidates based on their brightness and color.

They followed up on the most promising targets using: Webb’s NIRSpec microshutter array.

This process created three interesting targets with masses between three and eight Jupiters and surface temperatures between 830 and 1,500 degrees Celsius.

Computer models suggest that the smallest of these weighs just three to four times as much as Jupiter.

ESA astronomer Dr Catalina Alves de Oliveira said: “With current models, it is very easy to create a giant planet in a disk around a star.”

“But in this cluster, the object is unlikely to form as a disc, but instead as a star, with three Jupiters having a mass 300 times less than the Sun.”

“Then we have to ask how the star formation process takes place at such a very small mass.”

Two of the brown dwarfs identified by the research team exhibit spectral signatures of unidentified hydrocarbons, molecules that contain both hydrogen and carbon atoms.

The same infrared signature was detected in the atmospheres of Saturn and its moon Titan by NASA’s Cassini mission.

It has also been observed in the interstellar medium, the gas between stars.

“This is the first time this molecule has been detected in the atmosphere of an object outside our solar system,” Dr de Oliveira said.

“Models for brown dwarf atmospheres do not predict their existence. We are observing objects that are younger and have lower masses than ever before, and we are seeing something new and unexpected.” .”

a paper Regarding the survey results, astronomy magazine.

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KL Luman other. 2023. JWST survey of planetary mass brown dwarfs in IC 348. A.J. 167, 19; doi: 10.3847/1538-3881/ad00b7

Source: www.sci.news

NASA’s Webb and Hubble team up to capture the most vivid image of the universe

Posted on November 10, 2023 by Igor Mitreski

This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from NASA’s James Webb Space Telescope with visible-light data from NASA’s Hubble Space Telescope. Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)https://chat.openai.com/c/de5c3def-7d31-49b0-bd44-3d61675a3ae5

The result is a vivid landscape of the galaxy and more than a dozen newly discovered time-changing objects.

When the two flagship observatories come together, they reveal a wealth of new details that are only possible through their combined power. Webb and Hubble collaborated on studying MACS0416, a galaxy cluster about 4.3 billion light-years from Earth. Combining these data yields a prismatic panorama of blue and red. These colors provide clues to the galaxy’s distance. While the images themselves are surprising, researchers are already using these observations to fuel new scientific discoveries, such as identifying gravitationally expanded supernovae and ordinary stars.

This side-by-side comparison of galaxy cluster MACS0416 seen in optical light from the Hubble Space Telescope (left) and infrared light from the James Webb Space Telescope (right) reveals different details. Both images show hundreds of galaxies, but the Webb image shows galaxies that are invisible or only barely visible in the Hubble image. This is because Webb’s infrared vision can detect galaxies that are too far away or covered in dust to be seen by Hubble. (Light from distant galaxies is redshifted due to the expansion of the universe.) Webb’s total exposure time was about 22 hours, while the exposure time of the Hubble image was his 122 hours. Credit: NASA, ESA, CSA, STScI

NASA’s Webb Space Telescope and Hubble Space Telescope combine to create the most colorful view of the universe. NASA’s james webb space telescope and hubble space telescope They teamed up to study a vast galaxy cluster known as MACS0416. The resulting panchromatic images combine visible and infrared light to assemble one of the most comprehensive views of the universe ever captured. MACS0416, located approximately 4.3 billion light-years from Earth, is a pair of colliding galaxy clusters that will eventually merge to form an even larger cluster. Details revealed by the combination of stretching and contraction forces

This image reveals a wealth of detail only possible by combining the power of both space telescopes. This includes an abundance of galaxies outside the cluster and a scattering of light sources that change over time, possibly due to gravitational lensing (distortion and amplification of light from distant background sources). It is.

The galaxy cluster was the first in a series of unprecedented cosmic views into ultra-deep space from an ambitious joint Hubble program called Frontier Fields, launched in 2014. Hubble pioneered the search for some of the faintest and youngest galaxies ever detected. Webb’s infrared vision greatly enhances this deep observation by going even deeper into the early universe with its infrared vision.

This image of galaxy cluster MACS0416 highlights gravitational lensing background galaxies that existed about 3 billion years after the Big Bang. The galaxy contains an ephemeral object that the scientific team has named Mothra, whose brightness changes over time. Mothra is a star that is magnified at least 4,000 times. The researchers believe that Mothra is magnified not only by the gravity of the galaxy cluster MACS 0416, but also by an object known as a millilens, which weighs about the same as the globular cluster. Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)

Roger Windhorst of Arizona State University, principal investigator of the PEARLS program (Extragalactic Field for Reionization and Lensing Science), which carried out the Webb observations, said: “We are looking at objects that are farther away and fainter. “By doing so, we are building on Hubble’s legacy.”Understand image color and scientific goals

To create the images, the shortest wavelengths of light were generally color-coded as blue, the longest wavelengths as red, and the intermediate wavelengths as green. The wide range of wavelengths from 0.4 to 5 microns provides particularly vivid galactic landscapes.

These colors provide clues to the galaxy’s distance. The bluest galaxies, as most commonly detected by Hubble, are relatively nearby and often exhibit intense star formation, while the redder galaxies, as detected by Webb, tend to be more distant. Some galaxies appear very red because they contain large amounts of cosmic dust that tends to absorb bluer-colored starlight.

“Until we combine the Webb data with the Hubble data, we won’t get the full picture,” Windhorst said.Scientific discoveries and the “Christmas Tree Galaxy Cluster”

New Webb observations contribute to this aesthetic view, but they were taken for a specific scientific purpose. The research team combined his three epochs, each conducted a few weeks apart, with his fourth epoch by the CANUCS (Canadian NIRISS Unbiased Cluster Survey) research team. The goal was to search for objects that change in brightness observed over time, known as transients.

They identified 14 such transients across the visual field. Twelve of these transients are located in three galaxies that are highly magnified by gravitational lensing, and may be individual stars or star systems that are temporarily highly magnified. The remaining two transients are in more moderately expanded background galaxies and may be supernovae.

“We call MACS 0416 the Christmas Tree Galaxy Cluster, both because it is so colorful and because of the flashing lights found within it. Transients are seen everywhere. ” said Haojing Yang of the University of Missouri-Columbia, lead author of a paper describing the scientific results.

Among the transients the team identified, one in particular stood out. It is located in a galaxy that existed about 3 billion years after the Big Bang and has been magnified by at least 4,000 times. The research team nicknamed the system “Mothra” for its “monstrous nature” of being extremely bright and highly magnified. It joins another lensed star that researchers previously identified and named “Godzilla.” (Godzilla and Mothra are both giant monsters known as kaiju in Japanese movies.)

Interestingly, Mothra can also be seen in Hubble observations taken nine years ago. This is unusual because zooming in on stars this much requires a very specific alignment between the foreground galaxy cluster and the background stars. The mutual motion of stars and star clusters should eventually dissolve the alignment.

Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)”

Source: scitechdaily.com

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Tag Archives: Webb

Webb studies the intricate makeup of Jupiter’s ionosphere

Webb finds early universe protoglobular cluster

Webb uncovers puzzling alignment of protostellar outflows in the Ophiuchus Nebula

Webb Reveals the Inner Workings of the Crab Nebula

Webb discovers massive collision in Beta Pictoris star system

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

Webb finds the farthest galaxy ever recorded

Webb focuses on irregular galaxy NGC 4449

Webb captures stunning image of the Horsehead Nebula

Cool brown dwarf emits methane detected by Webb

Webb delves into the mysterious depths of Messier 82

Webb discovers complex organic compounds in interstellar ice approaching dual protostars

Webb observations provide new insights into the enigma of “Hubble tension”

Webb unveils stunning new images of NGC 1559

Webb uncovers incredible black hole in the ancient cosmos

Webb Observatory detects radiation from the neutron star remnant of supernova 1987A

Webb uncovers massive inactive galaxy with mature stars in the ancient cosmos

Webb discovers evidence of hydrothermal activity within Ellis and Makemake

New discoveries from the Webb telescope shed light on the origins of supermassive black holes and galaxies

Oldest black hole detected by Webb

New Observations by Webb Show Significant Conflict in Beta Pictoris

Webb observes auroras on cold brown dwarf star

Webb finds small, free-floating brown dwarf in star-forming cluster IC 348

NASA’s Webb and Hubble team up to capture the most vivid image of the universe