Showing posts with label Gemini Observatory. Show all posts
Showing posts with label Gemini Observatory. Show all posts

Tuesday, January 13, 2026

NuSTAR helps to identify the source of mysterious massive explosions



View more


Community observing program Shadow the Scientists took the public on a second tour of the famous interstellar visitor with live observations from the Gemini North telescope control room in Hawai‘i

Gemini North captured new images of Comet 3I/ATLAS after it reemerged from behind the Sun on its path out of the Solar System. The data were collected during a Shadow the Scientists session — a unique outreach initiative that invites students around the world to join researchers as they observe the Universe on the world’s most advanced telescopes.

On 26 November 2025, scientists used the Gemini Multi-Object Spectrograph (GMOS) on Gemini North at Maunakea in Hawai‘i to obtain images of the third-ever detected interstellar object, Comet 3I/ATLAS. The new observations reveal how the comet has changed after making its closest approach to the Sun. Gemini North is one half of the International Gemini Observatory, partly funded by the U.S. National Science Foundation (NSF) and operated by NSF NOIRLab.

After emerging from behind the Sun, 3I/ATLAS reappeared in the sky close to Zaniah, a triple-star system located in the constellation Virgo. These observations were taken as part of a public outreach initiative organized by NSF NOIRLab in collaboration with Shadow the Scientists, an initiative created to connect the public with scientists to engage in authentic scientific experiments, such as astronomy observing experiences on world-class telescopes. The scientific program was led by Bryce Bolin, a research scientist from Eureka Scientific.

This image is composed of exposures taken through four filters — blue, green, orange, and red. As exposures are taken, the comet remains fixed in the center of the telescope’s field of view. However, the positions of the background stars change relative to the comet, causing them to appear as colorful streaks in the final image.

In earlier images of the comet, captured during a Shadow the Scientists session hosted at Gemini South in Chile, it appears to have a red hue. However, in the new image released today, it appears to have a faint greenish glow. This is due to light emitted by gases in the comet’s coma that are evaporating as the comet heats up, including diatomic carbon (C2), a highly reactive molecule of two carbon atoms that emits light at green wavelengths.

What remains unknown is how the comet will behave as it leaves the Sun's vicinity and cools down. Many comets have a delayed reaction in experiencing the Sun's heat due to the lag in time that it takes for heat to make its way through the interior of the comet. A delay can activate the evaporation of new chemicals or trigger a comet outburst. Gemini will continue to monitor the comet as it leaves the Solar System and detect changes in its gas composition and outburst behavior.

This collaboration with Shadow the Scientists builds on NOIRLab’s tradition of combining cutting-edge science with public engagement, ensuring that remarkable cosmic events are shared as widely as possible. By involving learners directly in observing sessions and data collection, programs like this one not only advance knowledge but also inspire the next generation of explorers.

“Sharing an observing experience in some of the best conditions available gives the public a truly front-row view of our interstellar visitor,” says Bolin. “Allowing the public to see what we do as astronomers and how we do it also helps demystify the scientific and data collection process, adding transparency to our study of this fascinating object.”




More Information
NSF NOIRLab, the U.S. National Science Foundation center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), NSF Kitt Peak National Observatory (KPNO), NSF Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and NSF–DOE Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona.

The scientific community is honored to have the opportunity to conduct astronomical research on I’oligam Du’ag (K dge the very significant cultural role and reverence of I’oligam Du’ag to the Tohono O’odham Nation, and Maunakea to the Kanaka Maoli (Native Hawaiians) community.


Links


Contacts:
Bryce Bolin
bolin.astro@gmail.com
Research Scientist
Eureka Scientific, Inc
Josie Fenske
josie.fenske@noirlab.edu
Public Information Officer
NSF NOIRLab

Posted by at
Labels: , ,

Saturday, September 13, 2025

Gemini South Aids in Discovery of Elusive Cloud-Forming Chemical on Ancient Brown Dwarf

This artist’s illustration shows a brown dwarf that hosts an atmosphere filled with gas and dust clouds. A new study on an ancient brown dwarf called The Accident has unlocked clues into how clouds like these form on gas giant planets and how the time at which they formed can impact their chemical composition. NOIRLab/NSF/AURA/R. Proctor - Image Processing: M. Zamani (NSF NOIRLab) - Produced in part with SpaceEngine PRO.

Brown dwarfs are more massive than planets but not quite as massive as stars. Generally speaking, they have between 13 and 80 times the mass of Jupiter. A brown dwarf becomes a star if its core pressure gets high enough to start nuclear fusion. Credit: NASA/JPL-Caltech



10-billion-year-old brown dwarf nicknamed The Accident unlocks clues to the chemistry of cloud formation on planets like Jupiter and Saturn

In the first discovery of its kind, astronomers have found silane in the atmosphere of an ancient brown dwarf nicknamed The Accident. This molecule plays an important role in the formation of clouds in gas giant atmospheres, but for decades it has eluded detection in planets like Jupiter and Saturn. The discovery was made possible with complementary observations from the U.S. National Science Foundation-funded Gemini South telescope in Chile and NASA’s James Webb Space Telescope.

Brown dwarfs are peculiar objects that are too massive to be considered planets, but not massive enough to sustain nuclear fusion like a star. Among this curious class of objects, a brown dwarf nicknamed The Accident stands out for its unique mix of physical features, exhibiting characteristics previously seen only in warm, young brown dwarfs and others previously seen only in cool, ancient ones.

The Accident’s properties are highly unusual compared to all other known stars and brown dwarfs, so it slipped past typical detection methods. It was discovered accidentally in 2020 by a citizen scientist participating in the Backyard Worlds: Planet 9 citizen science project. Its strange light profile piqued the interest of astronomers, so they turned to two of the world’s most powerful ground- and space-based telescopes to peer into its atmosphere and better understand its nature and composition.

The investigation began with NSF NOIRLab astronomer Sandy Leggett obtaining near-infrared images of The Accident using the Gemini South telescope in Chile, one half of the International Gemini Observatory, funded in part by the U.S. National Science Foundation (NSF) and operated by NSF NOIRLab. This laid the groundwork for further investigations, led by NOIRLab astronomer Aaron Meisner, using NASA’s James Webb Space Telescope.

“The Accident is extremely faint, and Gemini South remains the only ground-based telescope that’s so far been able to detect it,” says Meisner, co-author on the paper presenting these results in Nature. “The Gemini detection set the stage for observations with JWST by allowing us to estimate the exposure time we would need to probe this enigmatic object’s deep atmospheric layers and get useful near-infrared data about its composition.”

The observations from Webb revealed a surprise. In The Accident’s atmosphere, the team found a conclusive signature of the chemical silane — silicon bonded with four hydrogen atoms. Planetary scientists have long predicted that this molecule exists in gas giants and that it plays an important role in the formation of clouds within their atmospheres. Despite decades of searching, it eluded detection in the atmospheres of our Solar System’s gas giants, Jupiter and Saturn, as well as the thousands of atmospheres scientists have studied on brown dwarfs and gas giants around other stars.

This marks the first discovery of silane in any brown dwarf, exoplanet, or Solar System object. The fact that this molecule hasn’t been detected anywhere except in a single, peculiar brown dwarf suggests something about the chemistry occurring in such ancient environments.

“Sometimes it’s the extreme objects that help us understand what’s happening in the average ones,” says Jackie Faherty, a researcher at the American Museum of Natural History in New York City and lead author on the paper.

Located about 50 light-years from Earth, The Accident likely formed 10–12 billion years ago, making it one of the oldest brown dwarfs ever discovered. The Universe is nearly 14 billion years old, meaning that The Accident formed at a time when the cosmos contained mostly hydrogen and helium, with trace amounts of other elements, including silicon. Over eons, elements like carbon, nitrogen, and oxygen formed in the cores of stars, meaning that planets and stars that formed more recently possess more of those elements.

The presence of silane in The Accident’s atmosphere suggests that, in very old objects, silicon can bond with hydrogen to form a light molecule that can reach the upper layers of a gas giant’s atmosphere. But in objects that formed more recently, like Jupiter and Saturn, the silicon bonds with the more readily available oxygen, creating heavier molecules that sink deep below the surface layers of the atmosphere, where they are undetectable by our telescopes.

The evidence uncovered in The Accident’s atmosphere confirms astronomers’ understanding of how clouds on gas giants form, and offers critical insight into how primordial formation can impact the composition of a planet’s atmosphere. Additionally, it reveals how a world formed billions of years ago can look drastically different than a world formed during the dawn of our Solar System.



More Information
research was presented in a paper titled “Silicate precursor silane detected in cold low-metallicity brown dwarf” appearing in Nature. DOI: 10.1038/s41586-025-09369-1

The team is composed of Jacqueline Faherty (American Museum of Natural History), Aaron Meisner (NSF NOIRLab), Ben Burningham (University of Hertfordshire), Channon Visscher (Dordt University), Genaro Suarez (American Museum of Natural History), Jonathan Gagne (Université de Montréal), Sherelyn Alejandro Merchan (American Museum of Natural History), Austin Rothermich (American Museum of Natural History), Michael Line (Arizona State University), Adam Burgasser (University of California San Diego), Adam Schneider (United States Naval Observatory), Dan Caselden (American Museum of Natural History), Davy Kirkpatrick (California Institute of Technology), Marc Kuchner (NASA Goddard Space Flight Center), Daniella Carolina Bardalez Gagliuffi (Amherst College), Peter Eisenhardt (JPL), Christopher Gelino (California Institute of Technology), Eileen Gonzales (San Francisco State University), Federico Marocco (California Institute of Technology), Sandy Leggett (NSF NOIRLab), Nicolas Lodieu (Instituto de Astrofísica de Canarias), Sarah Casewell (University of Leicester), Pascal Tremblin (Université Paris-Saclay), Michael Cushing (University of Toledo), María Rosa Zapatero Osorio (Center for Astrobiology, CSIC-INTA), Víctor Béjar (Instituto de Astrofísica de Canarias), Bartosz Gauza (University of Zielona Góra), Edward Wright (University of California), Mark Phillips (University of Edinburgh), Jun-Yan Zhang (Instituto de Astrofísica de Canarias), and Eduardo Martín (Instituto de Astrofísica de Canarias).

NSF NOIRLab, the U.S. National Science Foundation center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), NSF Kitt Peak National Observatory (KPNO), NSF Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and NSF–DOE Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona.

The scientific community is honored to have the opportunity to conduct astronomical research on I’oligam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence of I’oligam Du’ag to the Tohono O’odham Nation, and Maunakea to the Kanaka Maoli (Native Hawaiians) community.


Links



 Contacts:

Aaron Meisner
aaron.meisner@noirlab.edu
Astronomer
NSF NOIRLab

Sangy Leggett
sandy.leggett@noirlab.edu
Astronomer
International Gemini Observatory / NSF NOIRLab

Josie Fenske
josie.fenske@noirlab.edu
Public Information Officer
NSF NOIRLab

Posted by at
Labels: , ,

Monday, March 10, 2025

Gemini South Observes Ultra-Hot Nova Erupting With Surprising Chemical Signature

Artist’s Illustration of Extragalactic Recurrent Nova
Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick, M. Zamani

LMC68 Near-Infrared Spectra
Credit: International Gemini Observatory/NOIRLab/NSF/AURA/T. Geballe/J. Pollard




Astronomers uncover extremely hot and violent eruption from first ever near-infrared analysis of a recurrent nova outside of the Milky Way Galaxy

Using the Gemini South telescope, one half of the International Gemini Observatory, partly funded by the U.S. National Science Foundation and operated by NSF NOIRLab, and the Magellan Baade Telescope, astronomers have for the first time observed a recurring nova outside of the Milky Way in near-infrared light. The data revealed highly unusual chemical emissions as well as one of the hottest temperatures ever reported for a nova, both indicative of an extremely violent eruption.

Nova explosions occur in binary star systems in which a white dwarf — the dense remnant of a dead star — continually siphons stellar material from a nearby companion star. As the outer atmosphere of the companion gathers onto the surface of the white dwarf it reaches temperatures hot enough to spark an eruption.

Almost all novae discovered to-date have been observed to erupt only once. But a few have been observed to erupt more than once, and are classified as recurrent novae. The span between eruptions for these novae can vary from as little as one year to many decades [1].

Less than a dozen recurrent novae have been observed within our Milky Way Galaxy, while far more are extragalactic, meaning located outside of the Milky Way. Studying extragalactic novae helps build astronomers’ understanding of how different environments affect nova eruptions.

The first recurrent extragalactic nova to be observed was LMC 1968-12a (LMC68), located in the Large Magellanic Cloud — a satellite galaxy of the Milky Way. This nova has a recurrent timescale of about four years — the third-shortest of any nova — and consists of a white dwarf and a companion red subgiant (a star much larger than the Sun). It was discovered in 1968 and its eruptions have been observed fairly regularly since 1990.

Its most recent eruption, in August 2024, was first captured by the Neil Gehrels Swift Observatory, which has been closely monitoring the nova every month since its 2020 eruption. Given its known recurrent timescale, astronomers were anticipating this eruption, and LMC68 delivered right on cue.

Follow-up observations were conducted nine days after the initial outburst with the Carnegie Institution’s Magellan Baade Telescope, and 22 days after the initial outburst with the Gemini South telescope, one half of the International Gemini Observatory, funded in part by the U.S. National Science Foundation and operated by NSF NOIRLab.

Using the technique of spectroscopy [2], the team observed LMC68’s near-infrared light, which allowed them to study the nova’s ultra-hot phase during which many elements have been highly energized. By studying this phase astronomers can learn about the most extreme processes at play in the eruption. This study is the first ever near-infrared spectroscopic observation of an extragalactic recurrent nova.

After its initial eruption LMC68’s light faded rapidly, but Gemini South’s FLAMINGOS-2 instrument still captured a strong signal from ionized silicon atoms, specifically silicon atoms that have been stripped of nine of their 14 electrons, which requires incredible amounts of energy in the form of radiation or violent collisions.

In the earlier spectrum from Magellan, the near-infrared light from just the ionized silicon alone shined 95 times brighter than the light emitted by the Sun added up across all its wavelengths (X-ray, ultraviolet, visible, infrared, and radio). When Gemini observed the line several days later the signal had faded, but the silicon emission still dominated the spectrum.

“The ionized silicon shining at almost 100 times brighter than the Sun is unprecedented,” says Tom Geballe, NOIRLab emeritus astronomer and co-author of the paper appearing in the Monthly Notices of the Royal Astronomical Society. “And while this signal is shocking, it’s also shocking what’s not there.”

Novae found in the Milky Way typically emit numerous near-infrared signatures from highly-excited elements, but LMC68’s spectra contained only the ionized silicon feature. “We would’ve expected to also see signatures of highly energized sulfur, phosphorus, calcium and aluminum,” says Geballe.

“This surprising absence, combined with the presence and great strength of the silicon signature, implied an unusually high gas temperature, which our modeling confirmed,” adds co-author Sumner Starrfield, Regents Professor of Astrophysics at Arizona State University.

The team estimates that, during the nova’s early post-explosion phase, the temperature of the expelled gas reached 3 million degrees Celsius (5.4 million degrees Fahrenheit), making it one of the hottest novae ever recorded. This extreme temperature suggests a highly violent eruption, which the team theorizes is due to the conditions of the nova’s environment.

The Large Magellanic Cloud and its stars have a lower metallicity than the Milky Way, meaning it contains a lower abundance of elements heavier than hydrogen and helium, referred to as metals by astronomers. In high-metallicity systems, heavy elements trap heat on the white dwarf’s surface such that eruptions occur early in the accretion process. But without these heavy elements, more matter builds up on the white dwarf’s surface before it gets hot enough to ignite, causing the explosion to erupt with far greater violence. Additionally, the expelled gas collides with the atmosphere of the companion red subgiant, causing a huge shock that elevates the temperatures in the collision.

Prior to collecting their data, Starrfield predicted that the accretion of low-metallicity material onto a white dwarf would result in a more violent nova explosion. The observations and analysis presented here are broadly in agreement with that prediction.

“With only a small number of recurrent novae detected within our own galaxy, understanding of these objects has progressed episodically,” says Martin Still, NSF program director for the International Gemini Observatory. “By broadening our range to other galaxies using the largest astronomical telescopes available, like Gemini South, astronomers will increase the rate of progress and critically measure the behavior of these objects in different chemical environments.”



More Information

This research was presented in a paper titled “Near-infrared spectroscopy of the LMC recurrent nova LMCN 1968-12a” appearing in the Monthly Notices of the Royal Astronomical Society. DOI: 10.1093/mnras/stae2711

The team is composed of A. Evans (Keele University), D. P. K. Banerjee (Physical Research Laboratory, Ahmedabad), T. R. Geballe (International Gemini Observatory/NSF NOIRLab), A. Polin (Purdue University), E. Y. Hsiao (Florida State University), K. L. Page (University of Leicester), C. E. Woodward (University of Minnesota), S. Starrfield (Arizona State University).

NSF NOIRLab, the U.S. National Science Foundation center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), NSF Kitt Peak National Observatory (KPNO), NSF Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and NSF–DOE Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona.

The scientific community is honored to have the opportunity to conduct astronomical research on I’oligam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence of I’oligam Du’ag to the Tohono O’odham Nation, and Maunakea to the Kanaka Maoli (Native Hawaiians) community.


Links


Contacts:

Tom Geballe
tom.geballe@noirlab.edu
Emeritus Astronomer
NSF NOIRLab

Sumner Starrfield
sumner.starrfield@gmail.com
Regents Professor of Astrophysics
Arizona State University

Josie Fenske
josie.fenske@noirlab.edu
Jr. Public Information Officer
NSF NOIRLab

Posted by at
Labels: , , , ,

Wednesday, February 19, 2025

A Fiery Rose Captured by Gemini

International Gemini Observatory/NOIRLab/NSF/AURA. Image Processing: J. Miller & M. Rodriguez (International Gemini Observatory/NSF NOIRLab), T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), M. Zamani (NSF NOIRLab)


Videos


The NGC 2040 star cluster fuels the growth of this cosmic flower as the stellar life cycle unfolds within

Displaying wispy layers of red, orange and yellow, the nebula encasing NGC 2040 resembles a vibrant rose in this image captured by the Gemini South telescope, one half of the International Gemini Observatory, which is supported in part by the U.S. National Science Foundation and operated by NSF NOIRLab. This nebulous flower showcases the dramatic story of stellar life, death and rebirth.

NGC 2040 is a young open cluster of stars within the Large Magellanic Cloud, a satellite galaxy of the Milky Way, located about 160,000 light-years from Earth. It is a type of star cluster known as an OB association because it contains more than a dozen stars of the O and B spectral types. These stars lead short lives of only a few million years, during which they burn very hot before exploding as supernovae. The energy released by the explosions of these massive stars feeds the formation of NGC 2040’s structure, while the expelled material seeds the growth of the next generation of stars.

The veiled nebula’s delicate structure, resembling a Valentine’s Day rose, is revealed in this image captured with the Gemini South telescope, one half of the International Gemini Observatory, funded in part by the U.S. National Science Foundation and operated by NSF NOIRLab. The 8-meter optical/infrared telescope is perfectly suited to capturing both the bright stars and the diffuse glow of the cluster.

NGC 2040 contains mostly hydrogen and oxygen atoms. As these atoms are excited by the ultraviolet radiation from nearby massive stars, they emit light. This emitted light spans a range of wavelengths from the ultraviolet, through the visible, and into the infrared. Special filters on Gemini South then allow specific wavelengths, or colors, of this emitted light to pass through, like the deep red and orange of glowing hydrogen and the light blue of glowing oxygen. The bright white represents areas where there is an abundance of both.

NGC 2040 is so named because it is part of the New General Catalogue of deep sky objects, first compiled by John Dryer in 1888. More recent observations have revealed that it is part of a massive structure of interstellar gas known as LH 88, which is one of the largest active star-forming regions in the Large Magellanic Cloud. Over the next million years thousands of new stars will be born in the region.

Most of the stars in the Milky Way, including the Sun, likely formed within open clusters similar to NGC 2040. When the O and B stars end their lives as supernovae they will enrich the cluster with elements such as carbon, oxygen, and iron. Together with the bountiful hydrogen of the cluster, these elements provide the necessary ingredients for the formation of new stars, planets, and perhaps even life.

The bright stars seen in the image are widely separated, but their motions through space are similar, indicating that they have a common origin. The layered nebulous structures in LH 88 are the remnants of stars that have already died. The delicate leaves of the rose were formed by both the shockwaves from supernovae and the stellar winds of the O and B stars.

Taken as a whole, the rose of LH 88 tells a story of death and rebirth, where the dust of dead stars becomes the seeds of new stars and planetary systems. And like a rose the beauty of LH 88 is fleeting. Within a few million years — a brief moment of cosmic time — the gas and dust will be either gathered into young stars or cast off into interstellar space. The stars formed within the cluster will have moved on to their own journeys through their galaxy.



More Information
NSF NOIRLab, the U.S. National Science Foundation center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), NSF Kitt Peak National Observatory (KPNO), NSF Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and NSF–DOE Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona.

The scientific community is honored to have the opportunity to conduct astronomical research on I’oligam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence of I’oligam Du’ag to the Tohono O’odham Nation, and Maunakea to the Kanaka Maoli (Native Hawaiians) community.


Links


 Contacts:

Josie Fenske
josie.fenske@noirlab.edu
Jr. Public Information Officer NSF NOIRLab

Posted by at
Labels: , , , , ,

Wednesday, November 15, 2023

Dwarf galaxies stripped of their stars prove to be the missing link in the formation of rare ultra-compact dwarf galaxies


This illustration shows a dwarf galaxy in the throes of transitioning to an ultra-compact dwarf galaxy as it’s stripped of its outer layers of stars and gas by a nearby larger galaxy. Ultra-compact dwarf galaxies are among the densest stellar groupings in the Universe. Being more compact than other galaxies with similar mass, but larger than star clusters — the objects they most closely resemble — these mystifying objects have defied classification. The missing piece to this puzzle has been a lack of sufficient transitional, or intermediate objects to study. A new galaxy survey, however, fills in these missing pieces to show that many of these enigmatic objects are likely formed from the destruction of dwarf galaxies. Credit:NOIRLab/NSF/AURA/M. Zamani, download Large JPEG

A continuum of galaxies captured at different stages of the transformation process from a dwarf galaxy to an ultra-compact dwarf galaxy (UCD). These objects are located near the supergiant elliptical galaxy M87, the dominant member of the neighboring Virgo Cluster. Credit: NOIRLab/NSF/AURA/NASA/R. Gendler/K. Wang. download Large JPEG

NGC 3628 and an example of an ultra-compact dwarf galaxy (no annotations)
ANGC 3628, sometimes nicknamed the Hamburger Galaxy or Sarah's Galaxy, is an unbarred spiral galaxy about 35 million light-years away in the constellation Leo. Extending to the left of NGC 3628 for around 300,000 light-years is a ‘tidal tail’ — an elongated region of stars that arises as a result of gravitational interaction with another galaxy. Embedded within this tidal tail is the ultra-compact dwarf galaxy known as NGC 3628-UCD1. Credit: CTIO/NOIRLab/DOE/NSF/AURA. Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab), & D. de Martin (NSF’s NOIRLab). download Large JPEG

NGC 3628 and an example of an ultra-compact dwarf galaxy (annotated)
NGC 3628, sometimes nicknamed the Hamburger Galaxy or Sarah's Galaxy, is an unbarred spiral galaxy about 35 million light-years away in the constellation Leo. Extending to the left of NGC 3628 for around 300,000 light-years is a ‘tidal tail’ — an elongated region of stars that arises as a result of gravitational interaction with another galaxy. Embedded within this tidal tail is the ultra-compact dwarf galaxy known as NGC 3628-UCD1. Credit: CTIO/NOIRLab/DOE/NSF/AURA. Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab), & D. de Martin (NSF’s NOIRLab).  download Large JPEG


Astronomers using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, have captured the eroding remains of more than 100 dwarf galaxies as they transition into ultra-compact dwarf galaxies, objects with masses much greater than star clusters yet much smaller than dwarf galaxies. These findings confirm that many ultra-compact dwarf galaxies are likely the fossil remains of normal dwarf galaxies that have been stripped of their outer layers.

Ultra-compact dwarf galaxies (UCDs) are among the densest stellar groupings in the Universe. Being more compact than other galaxies with similar mass, but larger than star clusters — the objects they most closely resemble — these mystifying objects have defied classification. The missing piece to this puzzle has been a lack of sufficient transitional, or intermediate objects to study. A new galaxy survey, however, fills in these missing pieces to show that many of these enigmatic objects are likely formed from the destruction of dwarf galaxies.

The idea that UCDs are remnants of disrupted dwarf galaxies has been proposed since they were discovered over two decades ago. However, previous searches have not revealed the large population of galaxies-in-transition that you would expect to find. So an international team of astronomers conducted a systematic search for these intermediate-stage objects around the Virgo Cluster, a grouping of thousands of galaxies in the direction of the constellation Virgo. Using the Gemini North telescope near the summit of Maunakea in Hawaiʻi, the team identified more than 100 of these missing-link galaxies that show every stage of the transformation process.

“Our results provide the most complete picture of the origin of this mysterious class of galaxy that was discovered nearly 25 years ago,” said NOIRLab astronomer Eric Peng, a co-author on the paper describing these results appearing in the journal Nature. “Here we show that 106 small galaxies in the Virgo cluster have sizes between normal dwarf galaxies and UCDs, revealing a continuum that fills the ‘size gap’ between star clusters and galaxies.”

The team compiled their sample by first looking at images from the Next Generation Virgo Cluster Survey, taken with the Canada-France-Hawaiʻi Telescope. And though they were able to identify hundreds of candidate UCD progenitors, they were unable to confirm their true nature. The obstacle was that UCDs that are surrounded by envelopes of stars are indistinguishable from normal galaxies that are located farther away beyond the Virgo Cluster.

To distinguish the candidate UCD progenitors from the background galaxies, the team performed follow-up spectroscopic studies with Gemini North to obtain more concrete measurements of their distances. These observations allowed the astronomers to eliminate all of the background galaxies from their samples until only the UCDs within the Virgo Cluster remained.

Scattered among this vast survey are many dwarf galaxies that contain ultra-compact central star clusters. These galaxies represent the early stages of the transformation process and suggest that after neighboring massive galaxies strip these dwarfs of their outer layers of stars and gas, what remains will be an object identical to the late-stage UCDs that have already been identified.

The researchers also found many objects with very extended and diffuse stellar envelopes around them, indicating that they are currently in the throes of transitioning as their stars and dark matter is stripped away. Within their extensive sample the team identified objects at several other stages of the evolutionary process that, when placed in sequence, tell a compelling story of the morphology of UCDs. Furthermore, nearly all the candidates were near to massive galaxies, suggesting that their local environment plays an important role in their formation.

“Once we analyzed the Gemini observations and eliminated all the background contamination, we could see that these transition galaxies existed almost exclusively near the largest galaxies. We immediately knew that environmental transformation had to be important,” said Kaixiang Wang, a PhD student at Peking University and lead author of the paper.

Besides identifying the environment UCDs live in, these results also lend valuable insight into how many of these objects there are and what the full sequence of their evolutionary change looks like. “It’s exciting that we can finally see this transformation in action,” said Peng. “It tells us that many of these UCDs are visible fossil remnants of ancient dwarf galaxies in galaxy clusters, and our results suggest that there are likely many more low-mass remnants to be found,” he added.

“This study illustrates how large surveys can improve our understanding of the biggest questions in astronomy, like galaxy evolution,” says Chris Davis, NSF Program Director for NOIRLab. “NSF’s NOIRLab is a world leader in supporting astronomical surveys and — importantly — providing community and public access to the data and the amazing resulting discoveries.”



More information

This research was presented in a paper appearing in Nature. DOI: 10.1038/s41586-023-06650-z
The team is composed of K. Wang (Peking University), E. W. Peng (NSF’s NOIRLab), C. Liu (Shanghai Jiao Tong University), J. Christopher Mihos (Case Western Reserve University), P. Côté (National Research Council of Canada), L. Ferrarese (National Research Council of Canada), M. Taylor (University of Calgary), J. P. Blakeslee (NSF’s NOIRLab), J. Cuillandre (Universite! Paris Diderot), P. Duc (Université de Strasbourg), P. Guhathakurta (University of California Santa Cruz), S. Gwyn (National Research Council of Canada), Y. Ko (Korea Astronomy and Space Science Institute), A. Lançon (Université de Strasbourg), S. Lim (Yonsei University), L. A. MacArthur (Princeton University), T. Puzia (Pontificia Universidad Católica de Chile), J. Roediger (National Research Council of Canada), L. V. Sales (University of California), R. Sanchez-Janssen (Royal Observatory Edinburgh), C. Spengler (Pontificia Universidad Católica de Chile), E. Toloba (University of the Pacific), H. Zhang (University of Science and Technology of China), & M. Zhu (Peking University).

NSF’s NOIRLab, the US center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.



Links


 Contacts:

Eric Peng
NSF’s NOIRLab
Email: eric.peng@noirlab.edu

Kaixiang Wang
Peking University
Email: kaixiang.wang@pku.edu.cn

Josie Fenske
NSF’s NOIRLab Communications
Email: josie.fenske@noirlab.edu

Posted by at
Labels: , , , ,

Friday, July 14, 2023

Rare, Double-Lobe Nebula Resembles Overflowing Cosmic ‘Jug’

A billowing pair of nearly symmetrical loops of dust and gas mark the death throes of an ancient red-giant star, as captured by Gemini South, one half of the International Gemini Observatory, operated by NSF’s NOIRLab. The resulting structure, said to resemble an old style of English jug, is a rarely seen bipolar reflection nebula. Evidence suggests that this object formed by the interactions between the dying red giant and a now-shredded companion star. The image was obtained by NOIRLab’s Communication, Education & Engagement team as part of the NOIRLab Legacy Imaging Program.Credit: International Gemini Observatory/NOIRLab/NSF/AURA Image processing: T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), J. Miller (Gemini Observatory/NSF’s NOIRLab), M. Rodriguez (Gemini Observatory/NSF’s NOIRLab), M. Zamani (NSF’s NOIRLab), download: Large JPEG

Gemini South captures the spectacular end-of-life display of a red-giant star

A billowing pair of nearly symmetrical loops of dust and gas mark the death throes of an ancient red-giant star, as captured by Gemini South, one half of the International Gemini Observatory, operated by NSF’s NOIRLab. The resulting structure, said to resemble an old style of English jug, is a rarely seen bipolar reflection nebula. Evidence suggests that this object formed by the interactions between the dying red giant and a now-shredded companion star.

The glowing nebula IC 2220, nicknamed the Toby Jug Nebula owing to its resemblance to an old English drinking vessel, is a rare astronomical find. This reflection nebula, located about 1200 light-years away in the direction of the constellation Carina (the keel), is a double-lobed, or bipolar, cloud of gas and dust created and illuminated by the red-giant star at its center. This end-of-life phase of red giant stars is relatively brief, and the celestial structures that form around them are rare, making the Toby Jug Nebula an excellent case study into stellar evolution.

This image, captured by the Gemini South telescope, one half of the International Gemini Observatory, operated by NSF’s NOIRLab, showcases the Toby Jug Nebula’s magnificent, nearly symmetrical double-looped structure and glowing stellar heart. These features are unique to red giants transitioning from aging stars to planetary nebulae [1] and therefore offer astronomers valuable insight into the evolution of low- to intermediate-mass stars nearing the end of their lives as well as the cosmic structures they form.

At the heart of the Toby Jug Nebula is its progenitor, the red-giant star HR3126. Red giants form when a star burns through its supply of hydrogen in its core. Without the outward force of fusion, the star begins to contract. This raises the core temperature and causes the star to then swell up to 400 times its original size. Though HR3126 is considerably younger than our Sun — a mere 50 million years old compared to the Sun’s 4.6 billion years — it is five times the mass. This allowed the star to burn through its hydrogen supply and become a red giant much faster than the Sun.

As HR 3126 swelled, its atmosphere expanded and it began to shed its outer layers. The expelled stellar material flowed out into the surrounding area, forming a magnificent structure of gas and dust that reflects the light from the central star. Detailed studies of the Toby Jug Nebula in infrared light have revealed that silicon dioxide (silica) is the most likely compound reflecting HR3126’s light.

Astronomers theorize that bipolar structures similar to those seen in the Toby Jug Nebula are the result of interactions between the central red giant and a binary companion star. Previous observations, however, found no such companion to HR3126. Instead, astronomers observed an extremely compact disk of material around the central star. This finding suggests that a former binary companion was possibly shredded into the disk, which may have triggered the formation of the surrounding nebula. 

In about five billion years from now, when our Sun has burned through its supply of hydrogen, it too will become a red giant and eventually evolve into a planetary nebula. In the very distant future, all that will be left of our Solar System will be a nebula as vibrant as the Toby Jug Nebula with the slowly cooling Sun at its heart.

The image was processed by NOIRLab’s Communication, Education & Engagement team as part of the NOIRLab Legacy Imaging Program. The observations were made with Gemini South on Cerro Pachón in Chile using one of the dual Gemini Multi-Object Spectrographs (GMOS). Though spectrographs are designed to split light into various wavelengths for study, the GMOS spectrographs also have powerful imaging capabilities, as demonstrated by this exceptional view of the Toby Jug Nebula.

Notes

[1] The term “planetary nebulae” is a misnomer; they are unrelated to planets. The term was likely first used in the 1780s by astronomer William Herschel, who noted their seemingly round, planet-like shape when observed through early telescopes. 

NSF’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O'odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

Links

 

Contacts

Travis Rector
NSF's NOIRLab; University of Alaska
Tel: +1 907 786 1242
Email: tarector@alaska.edu

Josie Fenske
NSF’s NOIRLab
Email: josie.fenske@noirlab.edu

Charles Blue
Public Information Officer
NSF’s NOIRLab
Tel: +1 202 236 6324
Email: charles.blue@noirlab.edu

Source: Gemini Observatory

Posted by at
Labels: , , , , , ,

Friday, June 30, 2023

Never-Before-Seen Way to Annihilate a Star


Astronomers studying a powerful gamma-ray burst (GRB) with the International Gemini Observatory, operated by NSF’s NOIRLab, may have observed a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy. Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick/M. Zamani. download: Large JPEG


This artist's impression illustrates how astronomers studying a powerful gamma-ray burst (GRB) with the Gemini South telescope, operated by NSF’s NOIRLab, may have detected a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy. Credit:International Gemini Observatory/NOIRLab/NSF/AURA, M. Garlick, M. Zamani, K. O Chul, ESO/L. Calçada, NASA's Goddard Space Flight Center/CI Lab, N. Bartmann. Music: Stellardrone - Airglow.   Load Video


International Gemini Observatory traces gamma-ray burst to nucleus of ancient galaxy, suggesting stars can undergo demolition-derby-like collisions

Astronomers studying a powerful gamma-ray burst (GRB) with the Gemini South telescope, operated by NSF’s NOIRLab, may have observed a never-before-seen way to destroy a star. Unlike most GRBs, which are caused by exploding massive stars or the chance mergers of neutron stars, astronomers have concluded that this GRB came instead from the collision of stars or stellar remnants in the jam-packed environment surrounding a supermassive black hole at the core of an ancient galaxy.

Most stars in the Universe die in predictable ways, depending on their mass. Relatively low-mass stars like our Sun slough off their outer layers in old age and eventually fade to become white dwarf stars. More massive stars burn brighter and die sooner in cataclysmic supernova explosions, creating ultradense objects like neutron stars and black holes. If two such stellar remnants form a binary system, they also can eventually collide. New research, however, points to a long-hypothesized, but never-before-seen, fourth option.

While searching for the origins of a long-duration gamma-ray burst (GRB), astronomers using the Gemini South telescope in Chile, part of the International Gemini Observatory operated by NSF’s NOIRLab, and other telescopes [1], have uncovered evidence of a demolition-derby-like collision of stars or stellar remnants in the chaotic and densely packed region near an ancient galaxy’s supermassive black hole.

“These new results show that stars can meet their demise in some of the densest regions of the Universe where they can be driven to collide,” said Andrew Levan, an astronomer with Radboud University in The Netherlands and lead author of a paper appearing in the journal Nature Astronomy. “This is exciting for understanding how stars die and for answering other questions, such as what unexpected sources might create gravitational waves that we could detect on Earth.”

Ancient galaxies are long past their star-forming prime and would have few, if any, remaining giant stars, the principal source of long GRBs. Their cores, however, are teeming with stars and a menagerie of ultra-dense stellar remnants, such as white dwarf stars, neutron stars, and black holes.  Astronomers have long suspected that in the turbulent beehive of activity surrounding a supermassive black hole, it would only be a matter of time until two stellar objects collide to produce a GRB. Evidence for that type of merger, however, has been elusive.

The first hints that such an event had occurred were seen on 19 October 2019 when NASA’s Neil Gehrels Swift Observatory detected a bright flash of gamma rays that lasted for a little more than one minute. Any GRB lasting more than two seconds is considered “long.” Such bursts typically come from the supernova death of stars at least 10 times the mass of our Sun — but not always.

The researchers then used Gemini South to make long-term observations of the GRB’s fading afterglow to learn more about its origins. The observations allowed the astronomers to pinpoint the location of the GRB to a region less than 100 light-years from the nucleus of an ancient galaxy, which placed it very near the galaxy’s supermassive black hole. The researchers also found no evidence of a corresponding supernova, which would leave its imprint on the light studied by Gemini South.

“Our follow-up observation told us that rather than being a massive star collapsing, the burst was most likely caused by the merger of two compact objects,” said Levan. “By pinpointing its location to the center of a previously identified ancient galaxy, we had the first tantalizing evidence of a new pathway to ‘kill’ a star.”

In normal galactic environments, the production of long GRBs from colliding stellar remnants such as neutron stars and black holes is thought to be vanishingly rare. The cores of ancient galaxies, however, are anything but normal and there may be a million or more stars crammed into a region just a few light-years across. Such extreme population density may be great enough that occasional stellar collisions can occur, especially under the titanic gravitational influence of a supermassive black hole, which would perturb the motions of stars and send them careening in random directions. Eventually, these wayward stars would intersect and merge, triggering a titanic explosion that could be observed from vast cosmic distances.

It is possible that such events occur routinely in similarly crowded regions across the Universe but have gone unnoticed until this point. A possible reason for their obscurity is that galactic centers are brimming with dust and gas, which could obscure both the initial flash of the GRB and the resulting afterglow. This particular GRB, identified as GRB 191019A, may be a rare exception, allowing astronomers to detect the burst and study its after effects.

The researchers would like to discover more of these events. Their hope is to match a GRB detection with a corresponding gravitational-wave detection, which would reveal more about their true nature and confirm their origins, even in the murkiest of environments. The Vera C. Rubin Observatory, when it comes online in 2025, will be invaluable in this kind of research.

“Studying gamma-ray bursts like these is a great example of how the field is really advanced by many facilities working together, from the detection of the GRB, to the discoveries of afterglows and distances with telescopes like Gemini, through to detailed dissection of events with observations across the electromagnetic spectrum,” said Levan.

“These observations add to Gemini’s rich heritage developing our understanding of stellar evolution,” says Martin Still, NSF’s program director for the International Gemini Observatory. “The time sensitive observations are a testament to Gemini’s nimble operations and sensitivity to distant, dynamic events across the Universe.”



More Information

Reference: Levan, A. J., Malesani, D. B., Gompertz, B. P., et al. (2023) “A long-duration gamma-ray burst of dynamical origin from the nucleus of an ancient galaxy.” Nature Astronomy. DOI: 10.1038/s41550-023-01998-8

[1] Additional observations were made with the Nordic Optical Telescope and the NASA/ESA Hubble Space Telescope.

NSF’s NOIRLab, the US center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.



Links



Contacts:

Andrew Levan
Radboud University
Email: a.levan@astro.ru.nl

Charles Blue
Public Information Officer
NSF’s NOIRLab
Tel: +1 202 236 6324
Email: charles.blue@noirlab.edu
Posted by at
Labels: , , , , , ,

Thursday, June 22, 2023

Gemini North Detects Multiple Rock-Forming Elements in the Atmosphere of a Scorching Exoplanet


Astronomers using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, have made multiple detections of rock-forming elements in the atmosphere of a Jupiter-sized exoplanet, WASP-76b. The so-called “hot Jupiter” is perilously close to its host star, which is heating the planet’s atmosphere to astounding temperatures and vaporized rock-forming elements such as magnesium, calcium and iron, providing insight into how our own Solar System formed.Credit: International Gemini Observatory/NOIRLab/NSF/AURA/J. da Silva/Spaceengine/M. Zamani. download: Large JPEG

Chemistry of so-called ‘hot Jupiter’ provides new insights into the formation of our Solar System

Astronomers using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, have detected multiple rock-forming elements in the atmosphere of a Jupiter-sized exoplanet, WASP-76b. The planet is so perilously close to its host star that rock-forming elements — such as magnesium, calcium, and nickel — become vaporized and dispersed throughout its scorching atmosphere. This intriguing chemical profile provides new insights into the formation of planetary systems, including our own.

WASP-76b is a strange world. Located 634 light-years from Earth in the direction of the constellation of Pisces, the Jupiter-like exoplanet orbits its host star at an exceptionally close distance — approximately 12 times closer than Mercury is to the Sun — which heats its atmosphere to a searing 2000°C. Such extreme temperatures have “puffed up” the planet, increasing its volume to nearly six times that of Jupiter.

At such extreme temperatures, mineral- and rock-forming elements, which would otherwise remain hidden in the atmosphere of a colder gas-giant planet, can reveal themselves. 

Using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, an international team of astronomers has detected 11 of these rock-forming elements in the atmosphere of WASP-76b. The presence and relative amounts of these elements can provide key insights into exactly how giant gas planets form — something that remains uncertain even in our own Solar System. The results are published in the journal Nature. 

Since its discovery in 2013 during the Wide Angle Search for Planets (WASP) program, many astronomers have studied the enigmatic WASP-76b. These studies have led to the identification of various elements present in the hot exoplanet’s atmosphere. Notably, in a study published in March 2020, a team concluded that there could be iron rain on the planet.

Aware of these existing studies, Stefan Pelletier, a PhD student with the Trottier Institute for Research on Exoplanets at the Université de Montréal and lead author on the paper, was inspired to explore the mysteries of this strange exoplanet and the chemistry of its searing atmosphere. 

In 2020 and 2021, using Gemini North’s MAROON-X (a new instrument specially designed to detect and study exoplanets), Pelletier and his team observed the planet as it passed in front of its host star on three separate occasions. These new observations uncovered a number of rock-forming elements in the atmosphere of WASP-76b, including sodium, potassium, lithium, nickel, manganese, chromium, magnesium, vanadium, barium, calcium, and, as previously detected, iron.

Due to the extreme temperatures of WASP-76b’s atmosphere, the elements detected by the researchers,  which would normally form rocks here on Earth, are instead vaporized and thus present in the atmosphere in their gaseous forms. While these elements contribute to the composition of gas giants in our Solar System, those planets are too cold for the elements to vaporize into the atmosphere making them virtually undetectable.

“Truly rare are the times when an exoplanet hundreds of light-years away can teach us something that would otherwise likely be impossible to know about our own Solar System,” said Pelletier. “That is the case with this study.”

The abundance of many of these elements closely match the abundances found in both our Sun and the exoplanet’s host star. This may be no coincidence and provides additional evidence that gas-giant planets, like Jupiter and Saturn, form in a manner more akin to star formation — coalescing out of the gas and dust of a protoplanetary disk — rather than the gradual accretion and collision of dust, rocks, and planetesimals, which go on to form rocky planets, like Mercury, Venus, and Earth.

Another notable result of the study is the first-ever unambiguous detection of vanadium oxide (V2O5) on an exoplanet. “This molecule is of high interest to astronomers because it can have a great impact on the atmospheric structure of hot giant planets,” says Pelletier. “This molecule plays a similar role to ozone being extremely efficient at heating Earth’s upper atmosphere.” 

Pelletier and his team are motivated to learn more about WASP-76b and other ultra-hot planets. They also hope other researchers will leverage what they learned from this giant exoplanet and apply it to better our understanding of our own Solar System planets and how they came to be. 

“Available to astronomers across the globe, the International Gemini Observatory continues to deliver new insights that push our understanding of the physical and chemical structure of other worlds. Through such observational programs we are developing a clearer picture of the wider universe and our own place in it,” said NSF Gemini Observatory program director Martin Still.

“Generations of researchers have used Jupiter, Saturn, Uranus, and Neptune measured abundances for hydrogen and helium to benchmark formation theories of gaseous planets,” says Université de Montréal professor Björn Benneke, a co-author on the study. “Likewise, the measurements of heavier elements such as calcium or magnesium on WASP-76b will help further understanding the formation of gaseous planets.”

Notes

Reference: Pelletier, S, Benneke, B, and Ali-Dib, M, et al. (2023). “Vanadium oxide and a sharp onset of cold-trapping on a giant exoplanet.” Nature.

NSF’s NOIRLab, the US center for ground-based optical-infrared astronomy, operates the International Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.


Links



Contacts:

Stefan Pelletier
Université de Montréal, Montréal, Canada
Email:stefan.pelletier@umontreal.ca

Charles Blue
Public Information Officer
NSF’s NOIRLab
Tel: +1 202 236 6324
Email:charles.blue@noirlab.edu

Josie Fenske
NSF’s NOIRLab
Email: josie.fenske@noirlab.edu


Posted by at
Labels: , , ,
Subscribe to: Posts (Atom)