Tag Archives: disk

ALMA Achieves Best-Ever Image of Exoplanet Debris Disk

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Using the Atacama Large Millimeter/Submillimeter Array (ALMA), astronomers have unveiled stunning high-resolution images of 24 debris disks—dusty remnants that form after planetary systems complete their formation—showcasing the intricate transitional stages between the birth of planets and fully developed exoplanetary systems.

The ARKS gallery of faint debris disks reveals intricate shapes, including belts with multiple rings and sharp edges. Amber highlights the abundance of dust, while blue indicates carbon monoxide in gas-rich disks. Image credit: Sebastian Marino / Sorcha Mac Manamon / ARKS collaboration.

Young and mature planetary systems feature faint dust belts known as debris disks.

These disks are believed to result from collisions between large planetesimals, given dust’s brief lifespan against radiation and collisions.

Debris disks serve as the extrasolar equivalents of asteroids and the Kuiper Belt in our solar system.

With ages spanning from tens of millions to thousands of years, they offer a unique view into the final assembly of planetary systems.

Furthermore, they enable us to draw connections between protoplanetary disk structures and known mature exoplanetary populations.

Debris disks are significantly darker, appearing hundreds or thousands of times fainter than the luminous, gas-rich disks where planets are born.

Meredith Hughes, an astronomer at Wesleyan University, and her team have surmounted these challenges to produce the most detailed images to date of these disks.

Utilizing ALMA, they captured high-resolution images of 24 debris disks surrounding other stars.

This observation contributes to the ALMA survey aimed at resolving the Outer Kuiper Belt Substructure (ARKS).

“While we’ve often glimpsed ‘baby pictures’ of planet formation, the ‘teenage’ phase has remained elusive,” says Hughes.

Dr. Sebastian Marino, an astronomer at the University of Exeter, noted: “We’re observing genuine diversity—not just simple rings, but multi-ring belts and pronounced asymmetries, illustrating a dynamic and tumultuous phase in planetary history.”

ARKS stands as the largest and highest resolution survey of debris disks, akin to DSHARP, setting a new gold standard in the field.

Approximately one-third of the studied disks display distinct substructures, such as multiple rings and noticeable gaps, suggesting features left over from early planetary formation or shaped by planets over extended timescales.

Some disks retain the complex structure from earlier stages, while others have deteriorated into broad, smooth bands akin to the expected development of our solar system.

Many disks exhibit zones of tranquility and chaos, with vertically raised areas resembling unique objects in our solar system, blending classical Kuiper Belt objects with those disturbed by Neptune’s past migrations.

Some disks maintain gas longer than anticipated. In certain star systems, residual gas can influence the chemistry of developing planets or encourage dust to form extensive halos.

Numerous disks feature bright arcs or eccentric configurations, indicating gravitational effects from unseen exoplanets, scars left by planetary migration, or interactions between gas and dust.

Dr. Luca Matra, an astronomer at Trinity College, Dublin, remarked: “These disks encapsulate a period when planetary orbits were disrupted, akin to the massive impacts that shaped our early solar system.”

“By examining dozens of disks around stars of varying ages and types, ARKS aims to determine if their chaotic features are inherited, influenced by planets, or derived from other cosmic forces.”

“Understanding these nuances may shed light on whether our solar system’s history is unique or part of a common pattern.”

For more on this result, see the latest issue of Astronomy and Astrophysics.

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S. Marino et al. 2026. ALMA surveys to resolve the ExoKuiper belt substructure (ARKS). I. Motivation, sample, data reduction, and results overview. A&A 705, A195; doi: 10.1051/0004-6361/202556489

Source: www.sci.news

Scientists Uncover Largest Protoplanetary Disk Ever Detected Around Young Star

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IRAS 23077+6707: A Turbulent Protoplanetary Disk – Located approximately 1,000 light-years away, this young star exhibits an unexpectedly chaotic and turbulent surrounding protoplanetary disk, with material fragments extending farther than what astronomers have previously observed in similar systems. For more details, check the study here.

This Hubble image showcases the protoplanetary disk surrounding IRAS 23077+6707. Image credit: NASA / ESA / STScI / K. Monsch, CfA / J. DePasquale, STScI.

Protoplanetary disks, rich in dust and gas, form around young stars and serve as primary locations for planet formation.

The disk surrounding IRAS 23077+6707 spans approximately 644 billion km (400 billion miles), making it about 40 times the diameter of our solar system, reaching to the outer Kuiper belt.

This vast disk obscures the star, which scientists suggest could be a massive star or potentially a binary star system.

Not only is this disk the largest known for planet formation, but its unique characteristics also make it exceptionally rare.

“It’s uncommon to capture such fine detail in protoplanetary disks. The new Hubble images suggest that planetary nurseries might be much more dynamic and chaotic than we previously thought,” explained Dr. Christina Monsch, an astronomer at Harvard University and the Smithsonian Center for Astrophysics.

“Observing this disk nearly head-on reveals its delicate upper layers and asymmetrical features,” she added.

Both the NASA/ESA Hubble Space Telescope and the NASA/ESA/CSA James Webb Space Telescope have glimpsed similar structures, but IRAS 23077+6707 allows for unmatched visibility of its substructure in visible light.

This unique perspective makes it an exceptional laboratory for studying planet formation and the environments in which it occurs.

Edge-on, these disks resemble hamburgers, with bright upper and lower layers of glowing dust and gas, separated by a dark central lane.

In addition to its significant height, the new images reveal that vertical filament-like structures only appear on one side of the disk, indicating an uneven distribution of material.

“We were astonished by how asymmetric this disk appeared,” noted Dr. Joshua Bennett Lovell from the Harvard University & Smithsonian Center for Astrophysics.

“Hubble provides us with an exceptional view of the chaotic processes involved in the formation of disks and new planets. This process remains poorly understood, but these insights allow for fresh study opportunities.”

All planetary systems originate from a disk of gas and dust surrounding young stars. Over time, gas is absorbed by the star while planets form from the remaining material.

IRAS 23077+6707 might act as an extended analog to the early Solar System, with an estimated disk mass between 10 to 30 times that of Jupiter, providing sufficient material for multiple gas giant planets.

This and other discoveries make IRAS 23077+6707 an extraordinary case for examining planetary system formation.

“Theoretically, IRAS 23077+6707 could support a vast planetary system,” Dr. Monch stated.

“While planet formation may differ in such expansive conditions, the fundamental processes are likely akin to those in smaller systems.”

“At this point, we have more questions than answers, but these new images serve as a valuable foundation for understanding how planets evolve in diverse environments.”

Findings are set to be published in the Astrophysical Journal and can be accessed here.

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Christina Monche et al. 2025. Hubble reveals the complex multiscale structure of the edge-on protoplanetary disk IRAS 23077+6707. APJ in press. arXiv: 2510.11819

Source: www.sci.news

ALMA Discovers Heavy Water in Planet-Forming Disk Surrounding Distant Protostar

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An astronomer utilizing the Atacama Large Millimeter/Submillimeter Array (ALMA) has discovered double deuterated water (D2O), commonly known as “heavy water,” in the protoplanetary disk surrounding the protostar V883 Orionis, situated 1,300 light-years away in the Orion constellation. This finding indicates that some of the water found in comets—and even on Earth—might predate the stars themselves, offering transformative insights into the history of water in our solar system.

This artist’s impression illustrates the evolution of heavy water molecules, previously detected in giant molecular clouds, planet-forming disks, and comets, before ultimately reaching Earth. Image credit: NSF / AUI / NRAO of NSF / P. Vosteen / B. Saxton.

Investigating the primordial material from the protoplanetary disk that gave rise to our solar system suggests that water may have been transported to Earth via comet or asteroid impacts.

However, it remains uncertain whether the water ice present on these celestial objects formed primarily during the protoplanetary disk phase or if it is considerably older, originating from parent molecular clouds.

“This detection clearly demonstrates that the water found in the planet-forming disk around V883 Orionis predates the central star and must have formed during the early phases of star and planet formation,” stated Dr. Margot Rehmker, an astronomer at the University of Milan.

“This marks a significant leap in our understanding of the journey of water throughout planet formation and how this water potentially reached the solar system, including Earth, through similar mechanisms.”

The chemical fingerprinting of heavy water indicates that these molecules have withstood the turbulent processes of star and planet formation, traversing billions of kilometers through the cosmos and ending up in planetary systems like ours.

Rather than being completely destroyed and reformed within the disk, a significant portion of this water is inherited from the earliest, most frigid stages of star formation, serving as a cosmic remnant that may still exist on Earth today.

“Until now, it was uncertain whether most of the water in comets and planets was newly formed in young disks such as Orionis V883 or whether it was ‘pure’ from ancient interstellar clouds,” remarked Dr. John Tobin, an astronomer at the NSF National Radio Astronomy Observatory.

“The detection of heavy water using sensitive isotopic isomer ratios (D2oh2O) validates that this water is an ancient relic, forming a crucial link between clouds, disks, comets, and planets.”

“This finding is the first direct evidence that water can traverse through stars unaltered and intact, moving from clouds to the materials that constitute planetary systems.”

The team’s paper is published in this week’s edition of Nature Astronomy.

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M. Riemker et al. Primitive ice within a planet-forming disk identified by heavy water. Nat Astron published online October 15, 2025. doi: 10.1038/s41550-025-02663-y

Source: www.sci.news

Astronomers Discover Protoplanets Forming in Disk Gaps Around Young Solar Analogues

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Astronomers have successfully captured direct images of the 4.9 Jupiter Mass Protoplanet using ESO’s Very Large Telescope (VLT) sphere instruments, revealing clear gaps in the multi-ring protoplanetary disk. The star Whispit 2 (TYC 5709-354-1) is a solar analog, approximately 5 million years old, located 133 parsecs (434 light-years) away in the constellation Aquila.

This image taken with the ESO’s Very Large Telescope captures the first clear observation of a protoplanet within a disk featuring multiple rings. Image credit: ESO/Van Capelleveen et al.

A protoplanetary disk is typically accompanied by a ring and is a disc-shaped structure of gas and dust surrounding a young star.

These disks are the birthplaces of planets, with rings often suggesting the presence of hungry planets within the disk.

Initially, particles within the spinning disk begin to accumulate, drawing in more material from the surrounding disk until gravitational forces take hold, leading to the formation of an embryonic planet.

“Discovering Wispit 2B was an extraordinary experience. We were incredibly fortunate,” stated Dr. Richelle Van Capelleveen, an astronomer at the Leiden Observatory.

“Wispit 2, a younger version of our Sun, belongs to a small group of young stars, and we didn’t anticipate uncovering such an impressive system.”

“This system will serve as a benchmark for many years to come.”

“We’ve encountered many instances in our research,” remarked Christian Ginsky, a researcher at Galway University.

“However, in this case, we detected a remarkably unexpected and beautiful multi-ring dust disk.”

“Upon first encountering this multi-ring disk, I realized I had to attempt to detect the planets within it, immediately requesting follow-up observations.”

Astronomer captured a stunning transparent image of Whispit 2B situated in the gap of the disk, confirming that the planet orbits its host star.

“Wispit 2B marks the first clear detection of a planet on a multi-ring disk, providing an ideal setting for studying the interactions of planetary disks and their evolution,” they noted.

The Wispit 2B was observed in near-infrared light, retaining its brightness and heat from the initial formation phase.

The same is true for planets detected in visible light using the 6.5m Magellan Telescope MAGAO-X AO system and the large binocular interferometer (LBTI) Lmircam instrument.

This detection at specific wavelengths indicates that the planet is actively gathering gas as it develops its atmosphere.

“Located within the birth disk, Wispit 2B exemplifies a planet that can be utilized to explore current models of planet formation,” stated PhD student Chloe Lawler from Galway University.

The researchers estimated the radius of the disk surrounding Wispit 2B to be 380 AU (astronomical units) or about 380 times the distance between the Earth and the Sun.

“The discovery of Wispit 2B is remarkable,” commented Jake Byrne, a student pursuing an M.Sc. at Galway University.

The findings are detailed in two papers published in the Astrophysics Journal Letter.

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Richelle F. Van Capelvein et al. 2025. Wide separation planet (Wispit): A gap clear planet Wispit 2 of a multi-ring disc around a young solar-shaped star. apjl 990, L8; doi: 10.3847/2041-8213/ADF721

Laird M. Crows et al. 2025. Wide Separate Planet (Wispit): Discovery of GAPHα Protoplanet Wispit 2B Magao-X. apjl 990, L9; doi: 10.3847/2041-8213/adf7a5

Source: www.sci.news

Pink Floppy Disk and Bittle: Pioneering the Future of AI Music

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Feedback is your go-to source for the latest science and technology news from New Scientist. If you have intriguing stories for our readers, please reach out to us at Feedback@newscientist.com.

Sundown Showdown

Feedback has been aware for a while that there are numerous AI-generated music platforms, such as Spotify. I’ll admit, our familiarity was somewhat limited, as we still have a fondness for CDs.

However, we were surprised when New Scientist introduced us to Timothy Rebel, an indie rock band known as Velvet Sunset. Their track sounds like a blend of Coldplay and the Eagles, and their music appears to be generated by algorithms. The Instagram photos seem reminiscent of discarded concept art for Daisy Jones & Six.

Initially, the band denied any claims of being AI-generated. Their X Account discredited the theory that they are “generated,” insisting that their music was created during a long, sweat-filled night in a California bungalow.

Yet, there are no videos and none of the members have an online presence. Eventually, Rolling Stone interviewed Andrew Freron, identified as the band’s “creator.” He confessed it was all a form of “art hoax,” but then Frelon claimed this was also untrue, and the “band” released a statement distancing themselves from him. By now, Feedback has grown weary of this convoluted drama and simply wishes to express our confusion.

On that note, if you’re planning to create an AI band, consider Tim’s advice: “fully embrace the concept.” And if you decide to use a name reminiscent of Lou Reed, think twice. Tim suggests clever names like Rage I’m A Machine, The Bitles, TL (LM)c. Feedback adds playful ideas like pink floppy disks, Lanadel Array, Capchatonia, Alanis Microsoft, and Velvet.

Finally, the new generation of artists could certainly benefit from satirical acts, like a performer named Ai Yankovic.

Sodom Bomb

Science can be slow-paced, but occasionally, it leads to significant discoveries. Since September 2021, Scientific Report revealed some intriguing research claiming archaeological evidence of events influencing the biblical tales of Sodom and Gomorrah’s destruction.

According to the narrative, these cities were destroyed by divine intervention for their sins. In contrast, this study suggested a “. Tunguska-sized airburst,” akin to the 1908 explosion in Siberia, was responsible for the devastation.

This event purportedly occurred around 3600 years ago, annihilating the Bronze Age city of Elhammaum in present-day Jordan. Evidence included “a thick, carbon-rich destructive layer” across the city, alongside signs of “soot” and “melted metals like platinum, iridium, nickel, gold, silver, zircon, chromite, and quartz.”

However, on April 24th, the journal retracted this paper due to “methodological errors” and “misinterpretations.” Over four years, it faced considerable criticism and multiple revisions, as reported by Retraction Watch. Numerous images were manipulated in “inappropriate” ways, and it was noted that the burned and melted materials could have originated from smelting activities rather than explosions.

We found the comments on Pubpeer particularly amusing, with one commenter stating: “The north arrows and shadows in Figure 44C indicate that the sun is almost north-northeast, which is impossible in the Dead Sea.” This type of expert pedantry resonates with us.

In summary, someone produced a paper regarding two notorious cities, manipulated images contravening guidelines, and failed to properly assess alternate hypotheses. That’s quite the transgression.

Avocadon’t

Feedback receives numerous press releases, but we end up ignoring over 90%—mainly due to their irrelevance, like when we got inundated with wedding dress promotions. The primary issue is that most releases are rather dull.

However, one press release caught our attention on July 2nd with the subject line “Avocado is not an enemy.” This announcement was linked to the Wimbledon Tennis Tournament and addressed the decision to discontinue avocado services. The message contended, “It perpetuates myths unsupported by current data. In fact, avocados are among the most nutritious and environmentally friendly fruits available today.”

The release elaborated that avocados have a minimal water footprint and support small farms in places like Peru and South Africa, being rich in heart-healthy fats, fiber, and essential nutrients.

We found this proclamation rather impressive, and noticed the strong praise avocados receive from the World Avocado Organization.

As M. Rice-Davies once said in 1963, we can only add:

Have you spoken about feedback?

You can share your stories with us via email at feedback@newscientist.com. Don’t forget to include your home address. This week’s and past feedback can be found on our website.

Source: www.newscientist.com

Webb Sheds New Light on the Structural Evolution of Disk Galaxies

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Modern disk galaxies frequently display distinct thin and thick disks. The mechanisms driving the formation of these two discs and the timeline of their emergence are still unanswered questions. To investigate these issues, astronomers examined various epochs (statistical samples of 111 edge-on disk galaxies dating back up to 11 billion years, or approximately 2.8 billion years post-Big Bang) utilizing archived data from the NASA/ESA/CSA James Webb Space Telescope.

Webb/nircam composite images of a quarter of the team’s samples were sorted by increasing redshift. Image credit: Tsukui et al., doi: 10.1093/mnras/staf604.

Present-day disk galaxies often comprise extensive, star-rich outer disks alongside thin, star-like disks.

For instance, the thick discs of the Milky Way reach approximately 3,000 light-years in height, while the thin discs are roughly 1,000 light-years thick.

But what mechanisms lead to the formation of this dual disk structure?

“The thickness of high redshift discs, or unique measurements from the early universe, serve as benchmarks for theoretical research that can only be conducted using Webb,” states Takagi, an astronomer at the Australian National University.

“Typically, older, thicker disk stars are dim, while the younger, thinner disk stars dominate the galaxy.”

“However, Webb’s exceptional resolution allows us to observe and highlight faint older stars, enabling us to distinguish between two disk structures in a galaxy and measure their thickness separately.”

Through an analysis of 111 edge-on targets over cosmological time, astronomers studied both single-disc and double-disc galaxies.

The findings indicate that galaxies initially form a thick disk, which is followed by the formation of a thin disk.

The timing of this process is contingent on the galaxy’s mass: high-mass, single-disk galaxies transitioned to two-disk structures around 8 billion years ago.

In contrast, a thin disk emerged about 4 billion years ago within low-mass, single-disk galaxies.

“This is the first time we’ve resolved a thin star disk at such a high redshift,” remarked Dr. Emily Wysnioski from the Australian National University.

“The novelty becomes evident when observing the onset of thin star disks.”

“It was astonishing to witness a thin star disk from 8 billion years ago, and even further back.”

To elucidate the transition from a single thick disk to a dual-disk structure, as well as the timing differences between high-mass and low-mass galaxies, researchers expanded their investigation beyond the initial edge-on-galaxy samples. They examined data showing the movement of gases from large millimeter/sub-millimeter arrays (ALMAs) in Atacama and ground surveys.

By considering the movement of the galaxy’s gas disks, they found their results aligned with the “turbulent gas disk” scenario.

In this framework, the turbulent gas disks of the early universe catalyze intense star formation, leading to the creation of thick star disks.

As stars form, they stabilize the gas disks, diminishing turbulence and consequently resulting in thinner disks.

Larger galaxies can convert gas into stars more efficiently and thus calm down more quickly than their lower-mass counterparts, leading to the formation of the earlier thin disk.

“This study delineates structural differences between thin and thick discs, but we aim to explore further,” Dr. Tsukui mentioned.

“We look to incorporate the types of information typically acquired from nearby galaxies, such as stellar movement, age, and metallicity.”

“By doing so, we can bridge insights from both nearby and distant galaxies, enhancing our understanding of disk formation.”

Survey results were published in Monthly Notices of the Royal Astronomical Society.

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Takagi Tsukui et al. 2025. The emergence of thin and thick discs of galaxies across the history of the universe. mnras 540(4): 3493-3522; doi: 10.1093/mnras/staf604

Source: www.sci.news

Astronomers Uncover Magnetic Filaments Surrounding the Central Black Hole in Messier 77’s Accretion Disk

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Messier 77 is a relatively nearby and well-known bright spiral galaxy with a supermassive black hole at its center.

Messier 77 concept by artist. It is characterized by its powerful black hole and accretion disk, as well as the polarized light of water masers located outside the Milky Way. Image credit: NSF / AUI / NRAO / S. Dagnello.

Messier 77 is a barred spiral galaxy located 62 million light-years away in the constellation Cetus.

Also known as NGC 1068, LEDA 10266, and Cetus A, it has an apparent magnitude of 9.6.

Messier 77 was discovered in 1780 by French astronomer Pierre Méchain, who initially identified it as a nebula. Méchain then relayed this discovery to his colleague, the French astronomer Charles Messier.

Messier believed that the extremely bright objects he saw were clusters of stars, but as technology advanced, their true status as a galaxy was recognized.

At 100,000 light-years in diameter, Messier 77 is one of the largest galaxies in the Messier catalog, and its gravity is enough to twist and distort other galaxies nearby.

It is also one of the closest galaxies to active galactic nuclei (AGNs).

These active galaxies are among the brightest objects in the universe, emitting light in many if not all wavelengths, from gamma rays and X-rays to microwaves and radio waves.

But Messier 77's accretion disk is hidden by a thick cloud of dust and gas, despite being a popular target for astronomers.

Several light-years in diameter, the outer accretion disk is dotted with hundreds of different water maser sources that have been hinting at deeper structures for decades.

Masers are clear beacons of electromagnetic radiation that shine at microwave or radio wavelengths. In radio astronomy, water masers, observed at a frequency of 22 GHz, are particularly useful because they can shine through many of the dusts and gases that block the wavelengths of light.

Bucknell University astronomer Jack Gallimore and his colleagues began observing Messier 77 with two goals in mind: astronomical mapping of the galaxy's radio continuum and measuring the polarization of water masers.

“Messier 77 is a bit of a VIP among active galaxies,” says Dr. CM Violette Impellizzeri, an astronomer at the Leiden Observatory.

“There's an accretion disk right next to the black hole, and it's unusually powerful. And because it's so close, it's been studied in great detail.”

But the study authors looked at Messier 77 in an entirely new way.

Their observations were recently upgraded High sensitivity array (HSA) consists of the Karl G. Jansky Very Large Array, the Very Long Baseline Array, and NSF's NRAO telescope at the Green Bank Telescope.

By measuring the water maser's polarization and the continuous radio emission from Messier 77, they reveal the compact radio source, now known as NGC 1068*, and the mysterious extended structure of the fainter emission. I created a map to

Mapping the astronomical distribution of galaxies and their water masers reveals that they are spread along structural filaments.

“These new observations reveal that the maser spot filaments are actually arranged like beads on a string,” Dr. Gallimore said.

“We were stunned to see that there was an apparent offset, or displacement angle, between the radio continuum, which describes the structure of the galaxy's core, and the position of the maser itself.”

“The configuration is unstable, so we're probably looking at a magnetically ejected source.”

Measuring the polarization of these water masers with HSA revealed significant evidence of a magnetic field.

“No one has ever seen polarization in water masers outside of our galaxy,” Dr. Gallimore said.

“Similar to the loop structures seen as prominences on the Sun's surface, the polarization patterns of these water masers clearly indicate that there is also a magnetic field at the root of these light-year-scale structures.”

“Looking at the filaments and making sure the polarization vector is perpendicular to the filaments is key to confirming that they are magnetically driven structures. It's exactly what you expected. It’s a thing.”

Previous studies of the region have suggested patterns, usually related to magnetic fields, but such conclusions were until recently beyond the scope of observational techniques.

The discovery reveals evidence for a compact central radio source (the galaxy's supermassive black hole), distinct polarization of water masers indicating structure within Messier 77's magnetic field, and spectacular extended signatures across the radio frequency continuum. It became.

Taken together, these findings indicate that magnetic fields are the underlying driving force for these phenomena.

However, many mysteries remain. For example, within the radio continuum map there is a diffuse, faint protrusion that the team has dubbed the foxtail foxtail, extending northward from the central region.

“When we set out on this, we said to ourselves, 'Let's really push the limits and see if we can get good continuum and polarization data,' and those goals were both It was a success,” Dr. Gallimore said.

“Using the NSF NRAO High Sensitivity Array, we detected the polarization of a water megamaser for the first time. We also created a very surprising continuum map, which we are still trying to understand.”

a paper The results will be explained today. Astrophysics Journal Letter.

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Jack F. Gallimore others. 2024. Discovery of polarized water vapor megamaser emission in molecular accretion disks. APJL 975, L9; doi: 10.3847/2041-8213/ad864f

Source: www.sci.news

Hubble and Webb telescopes examine the planetary debris disk surrounding Vega

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

“Vega discs are smooth. Incredibly smooth.”

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

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

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

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

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

The two papers are astrophysical journal.

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

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

Source: www.sci.news

Astronomers Propose that X-ray and Ultraviolet Radiation Impact the Protoplanetary Disk in Cygnus OB2

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Cygnus OB2 is the giant young stellar association closest to the Sun.

In this new composite image, Chandra data (purple) shows the diffuse X-ray emission and young stars of Cygnus OB2, along with infrared data (red, green, blue, cyan) from NASA's now-retired Spitzer Space Telescope reveals young stars. And it creates cold dust and gas throughout the region. Image credits: NASA / CXC / SAO / Drake others. / JPL-California Institute of Technology / Spitzer / N. Walk.

At a distance of approximately 1,400 parsecs (4,600 light years), Cygnus OB2 It is a huge young body closest to the Sun.

It contains hundreds of double stars and thousands of low-mass stars.

Dr. Mario Giuseppe Guarcero of the National Institute of Astrophysics, Dr. Juan Facundo Albacete Colombo of the University of Rio Negro, and colleagues used NASA's Chandra X-ray Observatory to study various regions of Cygnus OB2. observed.

This deep observation mapped the diffuse X-ray glow between the stars and also provided an inventory of young stars within the cluster.

This inventory was combined with other inventories using optical and infrared data to create the best survey of young stars within the association.

“These dense stellar environments are home to large amounts of high-energy radiation produced by stars and planets,” the astronomers said.

“X-rays and intense ultraviolet radiation can have devastating effects on planetary disks and systems that are in the process of forming.”

The protoplanetary disk around the star naturally disappears over time. Part of the disk falls onto the star, and some is heated by X-rays and ultraviolet light from the star and evaporates in the wind.

The latter process, known as photoevaporation, typically takes 5 million to 10 million years for an average-sized star to destroy its disk.

This process could be accelerated if there is a nearby massive star that produces the most X-rays and ultraviolet light.

researchers Found Clear evidence that protoplanetary disks around stars actually die out much faster when they approach massive stars that produce large amounts of high-energy radiation.

Also, in regions where stars are more densely packed, the disk dies out faster.

In the region of Cygnus OB2, which has less high-energy radiation and fewer stars, the proportion of young stars with disks is about 40%.

In regions with higher-energy radiation and more stars, the proportion is about 18%.

The strongest influence, and therefore the worst location for a star to become a potential planetary system, is within about 1.6 light-years of the most massive star in the cluster.

In another study, the same team I looked into it Characteristics of the diffuse X-ray emission of Cygnus OB2.

They discovered that the high-energy, diffuse radiation originates from regions where winds of gas blown from massive stars collide with each other.

“This causes the gas to become hot and generate X-rays,” the researchers said.

“The low-energy release is likely caused by gas within the cluster colliding with gas surrounding the cluster.”

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MG Guarcero others. 2024. Photoevaporation and close encounters: How does the environment around Cygnus OB2 affect the evolution of the protoplanetary disk? APJS 269, 13; doi: 10.3847/1538-4365/acdd67

JF Albacete vs Colombo others. 2024. Diffuse X-ray emission in the Cygnus OB2 coalition. APJS 269, 14;doi: 10.3847/1538-4365/acdd65

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Astronomers find farthest rotating disk galaxy ever observed: REBELS-25

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According to one researcher, REBELS-25 existed until 700 million years after the Big Bang. paper Published in Royal Astronomical Society Monthly Notices.

This image shows the galaxy REBELS-25, observed by ALMA, superimposed on infrared images of other stars and galaxies. This infrared image was taken by ESO's Visible Infrared Survey Telescope for Astronomy (VISTA). Image credits: ALMA / ESO / National Astronomical Observatory of Japan / NRAO / Roland others. / Dunlop others. / Cas / Kare.

The galaxies we see today are very different from the chaotic, clumpy galaxies that astronomers typically observed in the early universe.

These messy early galaxies merge with each other and evolve into smoother shapes at an incredibly slow pace.

Current theory suggests that it would take billions of years of evolution for galaxies to become as ordered as our Milky Way, a rotating disk with an orderly structure like spiral arms.

However, the detection of REBELS-25 casts doubt on that timescale.

“Our understanding of galaxy formation predicts that most early galaxies appear small and messy,” said Dr Jacqueline Hodge, an astronomer at Leiden University.

In their study, Dr. Hodge and colleagues found that REBELS-25 existed at redshift z = 7.3 (when the universe was only 700 million years old), making it the most distant object ever discovered. They discovered that it was a strongly rotating disk galaxy.

“Seeing galaxies so similar to our own Milky Way and with strong rotational dominance adds to our understanding of how galaxies in the early universe evolved into the ordered galaxies of today's universe. It raises questions,” says Lucy Roland, a PhD student at Leiden University. University.

REBELS-25 was detected by the authors using the Atacama Large Millimeter/Submillimeter Array (ALMA).

To precisely identify the galaxy's structure and motion, they conducted follow-up observations at higher resolution with ALMA, confirming its record-breaking nature.

Surprisingly, the data suggested more developed features similar to the Milky Way, such as an elongated central bar and spiral arms, but more observations are needed to confirm this. Probably.

“Finding further evidence of a more evolved structure would be an interesting discovery, as this would be the most distant galaxy in which such a structure has been observed to date,” Rowland said.

“These future observations from REBELS-25, along with other discoveries of early rotating galaxies, could change our understanding of early galaxy formation and the evolution of the universe as a whole.”

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Lucy E. Rowland others. REBELS-25: Dynamically cold disk galaxy discovered at z = 7.31. MNRASpublished online October 7, 2024. doi: 10.1093/mnras/stae2217

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New study suggests Milky Way’s thinner disk formed within one billion years of the Big Bang

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Use of Data ESA's Gaia mission Astronomers have discovered a number of metal-poor stars that are more than 13 billion years old and in orbits similar to our sun.

Rotational motion of a young (blue) and an older (red) star similar to the Sun (orange). Image credit: NASA / JPL-Caltech / R. Hurt / SSC / Caltech.

“The Milky Way has a large halo, a central bulge and bar, and thick and thin disks,” said Dr Samir Nepal of the Leibniz Institute for Astrophysics Potsdam and his colleagues.

“Most of the stars are found in a thin disk of the so-called Milky Way galaxy, which revolves regularly around the galactic center.”

“Middle-aged stars like our Sun, which is 4.6 billion years old, belong to a thin disk that is generally thought to have begun to form between 8 and 10 billion years ago.”

Astronomers used the new Gaia data set to study stars within about 3,200 light-years of the Sun.

They found a surprisingly large number of very old stars in the thin disk orbit, most of which are over 10 billion years old, with some being over 13 billion years old.

These ancient stars show a wide range of metal compositions: some are very metal-poor (as expected), while others have twice the metal content of the much younger Sun, indicating that rapid metal enrichment occurred early in the evolution of the Milky Way.

“These ancient stars in the disk suggest that the formation of the Milky Way's thin disk began much earlier than previously thought, around 4 to 5 billion years ago,” Dr Nepal said.

“This study also reveals that the Galaxy underwent intense star formation early on, leading to rapid metal enrichment in its inner regions and the formation of a disk.”

“This discovery brings the Milky Way's disk formation timeline into line with that of high-redshift galaxies observed with the NASA/ESA/CSA James Webb Space Telescope and the Atacama Large Millimeter Array (ALMA).”

“This shows that cold disks can form and stabilize very early in the history of the universe, providing new insights into the evolution of galaxies.”

“Our study suggests that the Milky Way's thin disk may have formed much earlier than previously thought and that its formation is closely linked to an early chemical enrichment in the innermost regions of the galaxy,” said Dr Cristina Chiappini, astronomer at the Leibniz Institute for Astrophysics Potsdam.

“The combination of data from different sources and the application of advanced machine learning techniques has allowed us to increase the number of stars with high-quality stellar parameters, which is an important step leading our team to these new insights.”

of paper will be published in journal Astronomy and Astrophysics.

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Samir Nepal others2024. Discovery of local counterparts of disk galaxies at z > 4: The oldest thin disk in the Milky Way using Gaia-RVS. A&Ain press; arXiv: 2402.00561

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MUSE finds peculiar star surrounded by a luminous protoplanetary disk

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Astronomers Multi-unit spectroscopic probe The (MUSE) instrument on ESO’s Very Large Telescope (VLT) in Chile has imaged Propride, an externally illuminated protoplanetary disk around a young star, at 177-341 W. Orion Nebula.

This VLT/MUSE image shows propylid 177-341 W. Image courtesy of ESO / Aru others., doi: 10.1051/0004-6361/202349004.

Young stars are surrounded by a disk of gas and dust that gives rise to planets.

If another very bright and massive star is nearby, its light can heat up the young star’s disk and strip it of some of its material.

“Protoplanetary disks made of gas and dust emerge as a result of star formation processes and are the birth sites for planetary systems,” explained ESO astronomer Marie-Rees-Al and her colleagues.

“The evolutionary path of a protoplanetary disk and its ability to form planets depend on the surrounding environment, and we expect disks to undergo rapid changes in the presence of massive stars.”

“In massive clusters close to OB stars, ultraviolet (UV) radiation can cause the disk to photoevaporate externally, significantly reducing its size, mass, and lifetime.”

Astronomers used the MUSE instrument on ESO’s Very Large Telescope to observe 177-341W and 11 other dwarf stars in the Orion Nebula Cluster, about 400 parsecs away from the Sun.

“The stars encroaching on 177-341 W’s disk drop out of the frame after passing the upper right corner,” the researchers said.

“When that radiation collides with the material around the young star, it creates the bright bow-like structures we see in yellow.”

“The tail extending from the star toward the lower left corner is material being dragged away from 177-341 W by a star outside the field of view.”

“The colours displayed in this image represent different elements, including hydrogen, nitrogen, sulphur and oxygen,” the researchers added.

“But this is only a small part of the total data collected by MUSE. MUSE actually takes thousands of images simultaneously in different colors and wavelengths.”

a paper The findings have been published in the journal Astronomy and Astrophysics.

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M.-L. Al others2024. A kaleidoscope of irradiated disks: Propride MUSE observations of the Orion Nebula Cluster. I. Sample presentation and size of the ionization front. A&Ain press; doi: 10.1051/0004-6361/202349004

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Detecting Iron in the Accretion Disk Around the Supermassive Black Hole of NGC 4151: XRISM Observations

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NGC 4151 is a spiral galaxy located approximately 62 million light-years away in the northern constellation Hanabi.

This artist's concept shows possible locations for iron revealed in NGC 4151's XRISM X-ray spectrum. Image credit: Conceptual Image Lab, NASA's Goddard Space Flight Center.

The X-ray Imaging and Spectroscopy Mission (XRISM), a joint effort between JAXA and NASA, with extensive participation from ESA, launched from Japan's Tanegashima Space Center on September 6, 2023.

After beginning science operations in February 2024, the spacecraft focused on the supermassive black hole at the center of NGC 4151.

“XRISM's Resolve instrument captured a detailed spectrum of the region around the black hole,” said researcher Brian Williams, Ph.D., of NASA's Goddard Space Flight Center.

“The peaks and valleys are like chemical fingerprints that tell us what elements are present and can reveal clues about the fate of matter that approaches a black hole.”

NGC 4151's supermassive black hole holds more than 20 million times the mass of the Sun.

This galaxy is also active, meaning its center is unusually bright and changeable.

Gas and dust swirling toward the black hole forms an accretion disk around it, heated by gravity and frictional forces, creating fluctuations.

Some of the material at the edge of the black hole forms twin jets of particles that shoot out from either side of the disk at nearly the speed of light.

A bulging donut-shaped cloud of material called a torus surrounds the accretion disk.

XRISM's Resolve instrument captured data from the center of NGC 4151. The resulting spectrum reveals the presence of iron with a peak around 6.5 keV and a dip around 7 keV, thousands of times more energetic than the light visible to our eyes. Image credits: JAXA / NASA / XRISM Resolve / CXC / CfA / Wang et al. / Isaac Newton Telescope Group, La Palma Island / Jacobus Kapteyn Telescope / NSF / NRAO / VLA.

“In fact, NGC 4151 is one of the closest known active galaxies,” Dr. Williams and his colleagues said.

“Other missions, such as NASA's Chandra X-ray Observatory and the NASA/ESA Hubble Space Telescope, are conducting research to learn more about the interactions between black holes and their surroundings, allowing scientists to study galaxies. Find out how the supermassive black hole at the center of time grows throughout the universe.

“This galaxy is unusually bright in X-rays, making it an ideal early target for XRISM.”

“The NGC 4151 spectrum in Resolve shows a sharp peak at energies just below 6.5 keV, an iron emission line.”

Astronomers believe that much of the power in active galaxies comes from X-rays emanating from hot, blazing regions near black holes.

When the X-rays reflect off the cold gas inside the disk, the iron there fluoresces, producing a specific X-ray peak.

This allowed for a more accurate depiction of both the disk and the eruptive region much closer to the black hole.

“The spectrum also shows some dips around 7 keV,” the astronomers said.

“The iron present in the torus caused these dips as well, but due to absorption rather than emission of X-rays, because the material there is much cooler than in the disk.”

“All of this radiation is about 2,500 times more energetic than the light we can see with our eyes.”

“Iron is just one of the elements that XRISM can detect. The telescope can also detect sulfur, calcium, argon, and more, depending on the source.”

“Each one tells us something different about the cosmic phenomena that litter the X-ray sky.”

Source: www.sci.news

ALMA observes water vapor in young star’s protoplanetary disk

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Water molecules are key components in the formation of planetary systems. Astronomers using the Atacama Large Millimeter/Submillimeter Array (ALMA) have detected water vapor in the disk around the young star HL Taurus, where planets may be forming. Their analysis suggests that the hard lower limit for water vapor availability within the interior 17 astronomical units of the Taurus HL system is 3.7 Earth Oceans.

This ALMA image shows water vapor (blue tints) in the protoplanetary disk around HL Taurus. Near the center of the disk, where young stars live, the environment is hotter and the gas brighter. The red ring is a previous ALMA observation showing the distribution of dust around the star.Image credits: ALMA / ESO / National Astronomical Observatory of Japan / NRAO / Facchini other.

Water molecules are undoubtedly one of the most important molecular species in the entire universe.

Water is a highly efficient solvent, so it played a key role in the emergence of life as we know it on Earth.

For this reason, chemical characterization of exoplanetary atmospheres often focuses on detecting this specific molecule.

Water, formed from common hydrogen and oxygen atoms, is so abundant in both gas and ice form that it plays a fundamental role in the physics of planetary system formation.

Dr Stefano Facchini, an astronomer at the University of Milan, said: “We never imagined that we would be able to image oceans of water vapor in areas where planets are likely to form.”

The HL Taurus system is believed to be less than 100,000 years old and has a radius of about 17.9 billion km. It is located 450 light years away in the direction of the constellation Taurus.

The protoplanetary disk of HL Taurus is unusually large and bright, making it a perfect place to look for signs of planet formation.

New ALMA observations reveal that there is at least three times more water inside the disk than in Earth's entire ocean.

Dr Leonardo Testi, an astronomer at the University of Bologna, said: “It is truly amazing that we can not only detect water vapor 450 light-years from us, but also obtain detailed images and spatially resolve it.” said.

Spatially resolved observations with ALMA allow astronomers to determine the distribution of water in different regions of the disk.

“Participating in such an important discovery of the iconic HL Taurus disk was beyond my expectations given my first research experience in astronomy,'' said Dr. Mathieu Vander Donk, an astronomer at the University of Liege. he said.

Dr Facchini said: “Our recent images reveal that significant amounts of water vapor are present at distances from the star that include gaps where planets may now be forming.” said.

“This suggests that this water vapor could influence the chemical composition of planets that form in those regions.”

“To date, ALMA is the only facility capable of spatially resolving water in cold planet-forming disks,” said Professor Wouter Bremings, an astronomer at Chalmers University of Technology.

ESO astronomer Dr Elizabeth Humphreys said: “It's really exciting to be able to witness first-hand in photographs the ejection of water molecules from icy dust particles.”

“The dust particles that make up the disk are the seeds for planet formation, colliding and clumping together to form even larger bodies orbiting the star.”

“Our findings show how the presence of water influences the development of planetary systems, similar to our own solar system about 4.5 billion years ago,” Dr. Facchini said.

of findings It was published in the magazine natural astronomy.

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S. Facchini other. HL Resolved ALMA observations of water in the inner astronomical unit of the Tau disk. Nat Astron, published online on February 29, 2024. doi: 10.1038/s41550-024-02207-w

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ALMA discovers earthquake-like ripples in the disk of an old barred spiral galaxy

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astronomer using Atacama Large Millimeter/Submillimeter Array ALMA observed disk bending waves in BRI 1335-0417, the oldest known spiral galaxy, more than 12 billion years old. This unprecedented observation reveals the galaxy’s dynamic growth pattern, showing the motion of a vertically oscillating disk similar to ripples in a pond. This study is the first time such a phenomenon has been detected in an early galaxy.

This simulation shows how the galactic disk is disturbed and seismic ripples propagate throughout the disk. Image credit: Brand-Hawthorne & Tepper-Garcia, University of Sydney.

Bar structures play an important role in driving galaxy evolution and forming disk structures.

In galaxies, axisymmetric stellar bars exert a gravitational torque on the gas, driving it toward the galactic center and forming concentrated stellar structures such as bulges and core disks.

This process may also promote the accretion of gas onto black holes, which are observed as active galactic nuclei.

Bars can also cause radial migration of gas and stars, which is essential for explaining the stellar kinematics observed in galaxies similar to the Milky Way.

“Thanks to a cutting-edge telescope called ALMA, we have been able to observe the ancient galaxy BRI 1335-0417 in greater detail,” said lead author Dr Takafumi Tsukui, an astronomer at the Australian National University.

“In particular, we were interested in how gas moves within and across galaxies.”

“Gas is a key component for star formation and provides important clues about how galaxies actually drive star formation.”

In this case, Dr. Tsukui and his colleagues were not only able to capture the movement of gas around BRI 1335-0417, but also revealed the formation of seismic waves, a first for this type of early galaxy.

The galaxy’s disk moves similar to the ripples in a pond after a stone is thrown into it.

ALMA detected emission from carbon ions in the galaxy BRI 1335-0417. Image credit: ALMA / ESO / NAOJ / NRAO / T. Tsukui & S. Iguchi, doi: 10.1126/science.abe9680.

“The vertical oscillatory motion of the disk is due to external factors, such as new gas flowing into the galaxy or contact with other small galaxies,” Tsukui said.

“Both possibilities would bombard the galaxy with new fuel for star formation.”

“Furthermore, our study revealed rod-like structures within the disk.”

“The galactic rods can destroy gas and transport it towards the center of the galaxy.”

“The bar discovered at BRI 1335-0417 is the most remote known structure of its kind.”

“Taken together, these results point to the dynamic growth of young galaxies.”

“We know that early galaxies formed stars at much faster rates than modern galaxies,” said co-author Dr Emily Wisnioski, also from the Australian National University.

“This is also true for BRI 1335-0417, which has a similar mass to our Milky Way galaxy but forms stars hundreds of times faster.”

“We wanted to understand how gas is supplied to keep up with this rapid rate of star formation.”

“Spiral structures are rare in the early Universe, and exactly how they form remains unknown.”

“This study also provides important information about the most likely scenario.”

“While it is impossible to directly observe the evolution of galaxies, our observations only provide snapshots, so computer simulations can help piece together the story.”

of findings will appear in Royal Astronomical Society Monthly Notices.

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Takafumi Tsukui other. 2024. Disk bending waves detected in a barred spiral galaxy at redshift 4.4. MNRAS 527 (3): 8941-8949; doi: 10.1093/mnras/stad3588

Source: www.sci.news