2 min read
This NASA/ESA Hubble Space Telescope image features a stormy and highly active spiral galaxy named NGC 1792. Located over 50 million light-years from Earth in the constellation Columba (the Dove), the bright glow of the galaxy’s center is offset by the flocculent and sparkling spiral arms swirling around it.
NGC 1792 is just as fascinating to astronomers as its chaotic look might imply. Classified as a starburst galaxy, it is a powerhouse of star formation, with spiral arms rich in star-forming regions. In fact, it is surprisingly luminous for its mass. The galaxy is close to a larger neighbor, NGC 1808, and astronomers think the strong gravitational interaction between the two stirred up the reserves of gas in this galaxy. The result is a torrent of star formation, concentrated on the side closest to its neighbor, where gravity has a stronger effect. NGC 1792 is a perfect target for astronomers seeking to understand the complex interactions between gas, star clusters, and supernovae in galaxies.
Hubble studied this galaxy before. This new image includes additional data collected throughout 2025, providing a deeper view of the tumultuous activity taking place in the galaxy. Blossoming red lights in the galaxy’s arms mark Hydrogen-alpha (H-alpha) emission from dense clouds of hydrogen molecules. The newly forming stars within these clouds shine powerfully with ultraviolet radiation. This intense radiation ionizes the hydrogen gas, stripping away electrons which causes the gas to emit H-alpha light. H-alpha is a very particular red wavelength of light and a tell-tale sign of new stars.
Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
4 min read
For the first time, scientists have made a clear X-ray detection of chlorine and potassium in the wreckage of a star using data from the Japan-led XRISM (X-ray Imaging and Spectroscopy Mission) spacecraft.
The Resolve instrument aboard XRISM, pronounced “crism,” discovered these elements in a supernova remnant called Cassiopeia A or Cas A, for short. The expanding cloud of debris is located about 11,000 light-years away in the northern constellation Cassiopeia.
“This discovery helps illustrate how the deaths of stars and life on Earth are fundamentally linked,” said Toshiki Sato, an astrophysicist at Meiji University in Tokyo. “Stars appear to shimmer quietly in the night sky, but they actively forge materials that form planets and enable life as we know it. Now, thanks to XRISM, we have a better idea of when and how stars might make crucial, yet harder-to-find, elements.”
A paper about the result published Dec. 4 in Nature Astronomy. Sato led the study with Kai Matsunaga and Hiroyuki Uchida, both at Kyoto University in Japan. JAXA (Japan Aerospace Exploration Agency) leads XRISM in collaboration with NASA, along with contributions from ESA (European Space Agency). NASA and JAXA also codeveloped the Resolve instrument.
Stars produce almost all the elements in the universe heavier than hydrogen and helium through nuclear reactions. Heat and pressure fuse lighter ones, like carbon, into progressively heavier ones, like neon, creating onion-like layers of materials in stellar interiors.
Nuclear reactions also take place during explosive events like supernovae, which occur when stars run out of fuel, collapse, and explode. Elemental abundances and locations in the wreckage can, respectively, tell scientists about the star and its explosion, even after hundreds or thousands of years.
Some elements — like oxygen, carbon, and neon — are more common than others and are easier to detect and trace back to a particular part of the star’s life.
Other elements — like chlorine and potassium — are more elusive. Since scientists have less data about them, it’s more difficult to model where in the star they formed. These rarer elements still play important roles in life on Earth. Potassium, for example, helps the cells and muscles in our bodies function, so astronomers are interested in tracing its cosmic origins.
The roughly circular Cas A supernova remnant spans about 10 light-years, is over 340 years old, and has a superdense neutron star at its center — the remains of the original star’s core. Scientists using NASA’s Chandra X-ray Observatory had previously identified signatures of iron, silicon, sulfur, and other elements within Cas A.
In the hunt for other elements, the team used the Resolve instrument aboard XRISM to look at the remnant twice in December 2023. The researchers were able to pick out the signatures for chlorine and potassium, determining that the remnant contains ratios much higher than expected. Resolve also detected a possible indication of phosphorous, which was previously discovered in Cas A by infrared missions.
“Resolve’s high resolution and sensitivity make these kinds of measurements possible,” said Brian Williams, the XRISM project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Combining XRISM’s capabilities with those of other missions allows scientists to detect and measure these rare elements that are so critical to the formation of life in the universe.”
The astronomers think stellar activity could have disrupted the layers of nuclear fusion inside the star before it exploded. That kind of upheaval might have led to persistent, large-scale churning of material inside the star that created conditions where chlorine and potassium formed in abundance.
The scientists also mapped the Resolve observations onto an image of Cas A captured by Chandra and showed that the elements were concentrated in the southeast and northern parts of the remnant.
This lopsided distribution may mean that the star itself had underlying asymmetries before it exploded, which Chandra data indicated earlier this year in a study Sato led.
“Being able to make measurements with good statistical precision of these rarer elements really helps us understand the nuclear fusion that goes on in stars before and during supernovae,” said co-author Paul Plucinsky, an astrophysicist at the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts. “We suspected a key part might be asymmetry, and now we have more evidence that’s the case. But there’s still a lot we just don’t understand about how stars explode and distribute all these elements across the cosmos.”
By Jeanette Kazmierczak
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Media Contact:
Claire Andreoli
301-286-1940
NASA’s Goddard Space Flight Center, Greenbelt, Md.
2 min read
Today’s NASA/ESA Hubble Space Telescope image features the spiral galaxy NGC 4535, which is situated about 50 million light-years away in the constellation Virgo (the Maiden). Through a small telescope, this galaxy appears extremely faint, giving it the nickname ‘Lost Galaxy’. With a mirror spanning nearly eight feet (2.4 meters) across and its location above Earth’s light-obscuring atmosphere, Hubble can easily observe dim galaxies like NGC 4535 and pick out features like its massive spiral arms and central bar of stars.
This image features NGC 4535’s young star clusters, which dot the galaxy’s spiral arms. Glowing-pink clouds surround many of these bright-blue star groupings. These clouds, called H II (‘H-two’) regions, are a sign that the galaxy is home to especially young, hot, and massive stars that blaze with high-energy radiation. Such massive stars shake up their surroundings by heating their birth clouds with powerful stellar winds, eventually exploding as supernovae.
The image incorporates data from an observing program designed to catalog roughly 50,000 H II regions in nearby star-forming galaxies like NGC 4535. Hubble released a previous image of NGC 4535 in 2021. Both the 2021 image and this new image incorporate observations from the PHANGS observing program, which seeks to understand the connections between young stars and cold gas. Today’s image adds a new dimension to our understanding of NGC 4535 by capturing the brilliant red glow of the nebulae that encircle massive stars in their first few million years of life.
Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
4 min read
Astronomers have revolutionized our understanding of a collection of stars in the northern sky called the Pleiades. They used data from NASA’s TESS (Transiting Exoplanet Survey Satellite) and other observatories as NASA explores the secrets of the universe for the benefit of all, from the Moon to Mars and beyond.
By examining the rotation, chemistry, and orbit around the Milky Way of members of several different nearby stellar groups, the scientists identified a continuum of more than 3,000 stars arcing across 1,900 light-years. This Greater Pleiades Complex triples the number of stars associated with the Pleiades and opens new approaches for discovering similar dispersed star clusters in the future.
“The Pleiades are very well studied — we often use them as a benchmark in astronomical observations,” said Andrew Boyle, a graduate student at the University of North Carolina at Chapel Hill. “When I started this research, I didn’t expect the cluster to balloon to the size that it did. It really touches on a human note. In the Northern Hemisphere, we’ve been looking up at the Pleiades and telling stories about them for thousands of years, but there’s so much more to them than we knew.”
A paper about the result, led by Boyle, published Wednesday, Nov. 12, in the Astrophysical Journal.
The Pleiades is a bright cluster of stars, also known as Messier 45. This loose grouping of about 1,000 members was born roughly 100 million years ago from the same molecular cloud, a cold dense patch of gas and dust.
About six of the stars in the cluster are visible to the unaided eye during evenings from October to April in the northern constellation Taurus. This collection has also been known since antiquity as the Seven Sisters, although the seventh star is no longer visible.
Boyle and his team initially identified over 10,000 stars that could be related to the Pleiades. These stars were orbiting at a similar rate around our Milky Way galaxy according to data from ESA’s (European Space Agency) Gaia satellite.
They narrowed down that collection using stellar rotation data from TESS.
NASA’s TESS mission scans a wide swath of the sky for about a month at a time, looking for variations in the light from stars to spot orbiting planets. This technique also allows TESS to identify and monitor asteroids out to large distances, determining their spin and refining their shape. Such observations improve our understanding of asteroids in our solar system, which can aid in planetary defense.
Scientists can also use TESS data to determine how fast the stars are rotating by looking at regular fluctuations in their light caused when dark surface features called star spots come in and out of view. Because stellar rotation slows as stars age, the researchers were able to pick out the stars that were about the same age as the Pleiades.
The team also looked at the chemical abundances in potential members using data from ground-based missions like the Sloan Digital Sky Survey, which is led by a consortium of institutions.
“The core of the Pleiades is chemically distinct from the average star in a few elements like magnesium and silicon,” said Luke Bouma, a co-author and fellow at the Carnegie Science Observatories in Pasadena, California. “The other stars that we propose are part of the Greater Pleiades are chemically distinct in the same way. The combination of these three major lines of evidence — Milky Way orbits, ages, and chemistry — tells me that we’re on the right path when making these connections.”
The team members think that all the stars in the Greater Pleiades Complex formed in a tighter collection, like the stars in the young Orion cluster, about 100 million years ago. Over time, the cluster dispersed due to the explosive forces of internal supernovae and from the tidal forces of our galaxy’s gravity.
The result is a stream of stars arcing across the sky from horizon to horizon.
Boyle and Bouma are now working on what they call the TESS All-Sky Rotation Survey. This database will allow researchers to access the rotation information for over 8 million stars to discover even more hidden stellar connections like the Greater Pleiades Complex.
“Thanks to TESS, this team was able to shed new light on a fixture of astronomy,” said Allison Youngblood, the TESS project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “From distant stars and planets to asteroids in our solar system and machine learning models here on Earth, TESS continues to push the boundaries of what we can accomplish with large datasets that capture just a part of the complexity of our universe.”
By Jeanette Kazmierczak
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Media Contact:
Claire Andreoli
301-286-1940
NASA’s Goddard Space Flight Center, Greenbelt, Md.
2 min read
Stars of all ages are on display in this NASA/ESA Hubble Space Telescope image of the sparkling spiral galaxy called NGC 6000, located 102 million light-years away in the constellation Scorpius.
NGC 6000 has a glowing yellow center and glittering blue outskirts. These colors reflect differences in the average ages, masses, and temperatures of the galaxy’s stars. At the heart of the galaxy, the stars tend to be older and smaller. Less massive stars are cooler than more massive stars, and somewhat counterintuitively, cooler stars are redder, while hotter stars are bluer. Farther out along NGC 6000’s spiral arms, brilliant star clusters host young, massive stars that appear distinctly blue.
Hubble collected the data for this image while surveying the sites of recent supernova explosions in nearby galaxies. NGC 6000 hosted two recent supernovae: SN 2007ch in 2007 and SN 2010as in 2010. Using Hubble’s sensitive detectors, researchers can discern the faint glow of supernovae years after the initial explosion. These observations help constrain the masses of supernovae progenitor stars and can indicate if they had any stellar companions.
By zooming in to the right side of the galaxy’s disk in this image, you can see a set of four thin yellow and blue lines. These lines are an asteroid in our solar system that was drifting across Hubble’s field of view as it gazed at NGC 6000. The four lines are due to four different exposures recorded one after another with slight pauses in between. Image processors combined these four exposures to create the final image. The lines appear dashed with alternating colors because each exposure used a filter to collect very specific wavelengths of light, in this case around red and blue. Having these separate exposures of particular wavelengths is important to study and compare stars by their colors — but it also makes asteroid interlopers very obvious!
Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
NASA’s James Webb Space Telescope has provided the first direct measurements of the chemical and physical properties of a potential moon-forming disk encircling a large exoplanet. The carbon-rich disk surrounding the world called CT Cha b, which is located 625 light-years away from Earth, is a possible construction yard for moons, although no moons are detected in the Webb data.
The results published today in The Astrophysical Journal Letters.
The young star the planet orbits is only 2 million years old and still accreting circumstellar material. However, the circumplanetary disk discovered by Webb is not part of the larger accretion disk around the central star. The two objects are 46 billion miles apart.
Observing planet and moon formation is fundamental to understanding the evolution of planetary systems across our galaxy. Moons likely outnumber planets, and some might be habitats for life as we know it. But we are only now entering an era where we can witness their formation.
This discovery fosters a better understanding of planet and moon formation, say researchers. Webb’s data is invaluable for making comparisons to our solar system’s birth over 4 billion years ago.
“We can see evidence of the disk around the companion, and we can study the chemistry for the first time. We’re not just witnessing moon formation — we’re also witnessing this planet’s formation,” said co-lead author Sierra Grant of the Carnegie Institution for Science in Washington.
“We are seeing what material is accreting to build the planet and moons,” added main lead author Gabriele Cugno of the University of Zürich and member of the National Center of Competence in Research PlanetS.
Infrared observations of CT Cha b were made with Webb’s MIRI (Mid-Infrared Instrument) using its medium resolution spectrograph. An initial look into Webb’s archival data revealed signs of molecules within the circumplanetary disk, which motivated a deeper dive into the data. Because the planet’s faint signal is buried in the glare of the host star, the researchers had to disentangle the light of the star from the planet using high-contrast methods.
“We saw molecules at the location of the planet, and so we knew that there was stuff in there worth digging for and spending a year trying to tease out of the data. It really took a lot of perseverance,” said Grant.
Ultimately, the team discovered seven carbon-bearing molecules within the planet’s disk, including acetylene (C2H2) and benzene (C6H6). This carbon-rich chemistry is in stark contrast to the chemistry seen in the disk around the host star, where the researchers found water but no carbon. The difference between the two disks offers evidence for their rapid chemical evolution over only 2 million years.
A circumplanetary disk has long been hypothesized as the birthplace of Jupiter’s four major moons. These Galilean satellites must have condensed out of such a flattened disk billions of years ago, as evident in their co-planar orbits about Jupiter. The two outermost Galilean moons, Ganymede and Callisto, are 50% water ice. But they presumably have rocky cores, perhaps either of carbon or silicon.
“We want to learn more about how our solar system formed moons. This means that we need to look at other systems that are still under construction. We’re trying to understand how it all works,” said Cugno. “How do these moons come to be? What are their ingredients? What physical processes are at play, and over what timescales? Webb allows us to witness the drama of moon formation and investigate these questions observationally for the first time.”
In the coming year, the team will use Webb to perform a comprehensive survey of similar objects, to better understand the diversity of physical and chemical properties in the disks around young planets.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
To learn more about Webb, visit:
Read more: NASA’s Webb Finds Planet-Forming Disks Lived Longer in Early Universe
Explore more: ViewSpace Detecting Other Worlds: Direct Imaging
Explore more: How to Study Exoplanets: Webb and Challenges
Read more: Webb’s Star Formation Discoveries
Laura Betz
NASA’s Goddard Space Flight Center
Greenbelt, Maryland
laura.e.betz@nasa.gov
Ray Villard
Space Telescope Science Institute
Baltimore, Maryland
Christine Pulliam
Space Telescope Science Institute
Baltimore, Maryland
NASA’s James Webb Space Telescope has provided the first direct measurements of the chemical and physical properties of a potential moon-forming disk encircling a large exoplanet. The carbon-rich disk surrounding the world called CT Cha b, which is located 625 light-years away from Earth, is a possible construction yard for moons, although no moons are detected in the Webb data.
The results published today in The Astrophysical Journal Letters.
The young star the planet orbits is only 2 million years old and still accreting circumstellar material. However, the circumplanetary disk discovered by Webb is not part of the larger accretion disk around the central star. The two objects are 46 billion miles apart.
Observing planet and moon formation is fundamental to understanding the evolution of planetary systems across our galaxy. Moons likely outnumber planets, and some might be habitats for life as we know it. But we are only now entering an era where we can witness their formation.
This discovery fosters a better understanding of planet and moon formation, say researchers. Webb’s data is invaluable for making comparisons to our solar system’s birth over 4 billion years ago.
“We can see evidence of the disk around the companion, and we can study the chemistry for the first time. We’re not just witnessing moon formation — we’re also witnessing this planet’s formation,” said co-lead author Sierra Grant of the Carnegie Institution for Science in Washington.
“We are seeing what material is accreting to build the planet and moons,” added main lead author Gabriele Cugno of the University of Zürich and member of the National Center of Competence in Research PlanetS.
Infrared observations of CT Cha b were made with Webb’s MIRI (Mid-Infrared Instrument) using its medium resolution spectrograph. An initial look into Webb’s archival data revealed signs of molecules within the circumplanetary disk, which motivated a deeper dive into the data. Because the planet’s faint signal is buried in the glare of the host star, the researchers had to disentangle the light of the star from the planet using high-contrast methods.
“We saw molecules at the location of the planet, and so we knew that there was stuff in there worth digging for and spending a year trying to tease out of the data. It really took a lot of perseverance,” said Grant.
Ultimately, the team discovered seven carbon-bearing molecules within the planet’s disk, including acetylene (C2H2) and benzene (C6H6). This carbon-rich chemistry is in stark contrast to the chemistry seen in the disk around the host star, where the researchers found water but no carbon. The difference between the two disks offers evidence for their rapid chemical evolution over only than 2 million years.
A circumplanetary disk has long been hypothesized as the birthplace of Jupiter’s four major moons. These Galilean satellites must have condensed out of such a flattened disk billions of years ago, as evident in their co-planar orbits about Jupiter. The two outermost Galilean moons, Ganymede and Callisto, are 50% water ice. But they presumably have rocky cores, perhaps either of carbon or silicon.
“We want to learn more about how our solar system formed moons. This means that we need to look at other systems that are still under construction. We’re trying to understand how it all works,” said Cugno. “How do these moons come to be? What are their ingredients? What physical processes are at play, and over what timescales? Webb allows us to witness the drama of moon formation and investigate these questions observationally for the first time.”
In the coming year, the team will use Webb to perform a comprehensive survey of similar objects, to better understand the diversity of physical and chemical properties in the disks around young planets.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
To learn more about Webb, visit:
Read more: NASA’s Webb Finds Planet-Forming Disks Lived Longer in Early Universe
Explore more: ViewSpace Detecting Other Worlds: Direct Imaging
Explore more: How to Study Exoplanets: Webb and Challenges
Read more: Webb’s Star Formation Discoveries
3 min read
The NASA Community College Network (NCCN) and the American Astronomical Society (AAS) have teamed up to provide an exciting and impactful program that brings top astronomy researchers into the classrooms of community colleges around the United States.
The Harlow Shapley Visiting Lectureship Program, named for astronomer Harlow Shapley (1885-1972), has a history dating back to the 1950s, when it provided support for a scientist to give a series of astronomy-themed lectures at a college or university, coupled with a public talk to the local community. In 2024, AAS partnered with NCCN to broaden the impact of the Shapley lectureship program to community colleges, making use of NCCN’s existing network of 260 college instructors across 44 states and 120 participating Subject Matter Experts (SME) to “matchmake” community colleges with astronomers.
NCCN has supported the teaching of astronomy at community college since 2020. Community colleges serve a vital role in STEM education, with one-third of their students being first-generation college attendees and 64% being part-time students working jobs and raising families. Factor in that up to 40% of students taking introductory astronomy courses nationally each year do so at a community college, and the motivation behind NCCN and the initiatives of the AAS become clear.
In 2024, the pilot collaboration between NCCN and the AAS matched two community colleges — Chattanooga State Community College in Tennessee and Modesto Junior College in California — with SMEs from University of Virginia and Stanford University. In 2025, nine NCCN subject matter experts are engaging with 14 community colleges in six states. They are:
Joe Masiero (Caltech) at Grossmont Community College CA
Vivian U (Caltech) at Scottsdale & Chandler Gilbert Community Colleges AZ
Dave Leisawitz (NASA) & Michael Foley (Harvard) at Elgin Community College IL
Michael Rutkowski (MN State) at Dallas Area Colleges (five colleges) TX
Joe Masiero (Caltech) at Mt. San Jacinto College, Menifee Campus CA
Quyen Hart (STScI) at Casper College WY
Nathan McGregor (UCSC) at Yakima Valley College WA
Patrick Miller (Hardin-Simmons) at Evergreen Valley College CA
Kim Arcand (Harvard-Smithsonian) at Anne Arundel Community College MD
Natasha Batalha (NASA) at Modesto Junior College CA
Each visit of an AAS Shapley Lecturer is unique. The center of each event is the public Shapley Lecture, which is broadly advertised to the local community. Beyond the Shapley Lecture itself, host institutions organize a variety of local engagement activities – ranging from star parties and classroom visits to meeting with college deans and faculty – to make the most of their time with the Shapley Lecturer.
Astronomy instructor James Espinosa from Weatherford College said, “[The visiting Shapley Lecturer’s] visit made a permanent change in how my classes will be taught, in the sense that ‘honors’ projects will be available for ambitious students. I intend to keep in touch with him for several years to come, which is a big impact for our present and future students.”
Dr. Tom Rice, AAS Education Program Manager and AAS lead on the partnership with NCCN, stated, “The AAS’s Harlow Shapley Visiting Lectureship Program represents one of the most impactful ways that astronomers can share our scientific understanding with the widest possible audience, and I am very proud that we have partnered with the SETI Institute and NASA to bring astronomers to their network of community colleges.”
NCCN is supported by NASA under cooperative agreement award number 80NSSC21M0009 and is part of NASA’s Science Activation Portfolio. Learn more about how Science Activation connects NASA science experts, real content, and experiences with community leaders to do science in ways that activate minds and promote deeper understanding of our world and beyond: https://science.nasa.gov/learn/about-science-activation/.
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
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2 min read
This NASA/ESA Hubble Space Telescope image features a galaxy that’s hard to categorize. The galaxy in question is NGC 2775, which lies 67 million light-years away in the constellation Cancer (the Crab). NGC 2775 sports a smooth, featureless center that is devoid of gas, resembling an elliptical galaxy. It also has a dusty ring with patchy star clusters, like a spiral galaxy. Which is it: spiral or elliptical — or neither?
Because we can only view NGC 2775 from one angle, it’s difficult to say for sure. Some researchers classify NGC 2775 as a spiral galaxy because of its feathery ring of stars and dust, while others classify it as a lenticular galaxy. Lenticular galaxies have features common to both spiral and elliptical galaxies.
Astronomers aren’t certain of exactly how lenticular galaxies come to be, and they might form in a variety of ways. Lenticular galaxies might be spiral galaxies that merged with other galaxies, or that have mostly run out of star-forming gas and lost their prominent spiral arms. They also might have started out more like elliptical galaxies, then collected gas into a disk around them.
Some evidence suggests that NGC 2775 merged with other galaxies in the past. Invisible in this Hubble image, NGC 2775 has a tail of hydrogen gas that stretches almost 100,000 light-years around the galaxy. This faint tail could be the remnant of one or more galaxies that wandered too close to NGC 2775 before being stretched apart and absorbed. If NGC 2775 merged with other galaxies in the past, it could explain the galaxy’s strange appearance today.
Most astronomers classify NGC 2775 as a flocculent spiral galaxy. Flocculent spirals have poorly defined, discontinuous arms that are often described as “feathery” or as “tufts” of stars that loosely form spiral arms.
Hubble previously released an image of NGC 2775 in 2020. This new version adds observations of a specific wavelength of red light emitted by clouds of hydrogen gas surrounding massive young stars, visible as bright, pinkish clumps in the image. This additional wavelength of light helps astronomers better define where new stars are forming in the galaxy.
Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
NASA’s James Webb Space Telescope has revealed a colorful array of massive stars and glowing cosmic dust in the Sagittarius B2 molecular cloud, the most massive and active star-forming region in our Milky Way galaxy.
“Webb’s powerful infrared instruments provide detail we’ve never been able to see before, which will help us to understand some of the still-elusive mysteries of massive star formation and why Sagittarius B2 is so much more active than the rest of the galactic center,” said astronomer Adam Ginsburg of the University of Florida, principal investigator of the program.
Sagittarius B2 is located only a few hundred light-years from the supermassive black hole at the heart of the galaxy called Sagittarius A*, a region densely packed with stars, star-forming clouds, and complex magnetic fields. The infrared light that Webb detects is able to pass through some of the area’s thick clouds to reveal young stars and the warm dust surrounding them.
However, one of the most notable aspects of Webb’s images of Sagittarius B2 are the portions that remain dark. These ironically empty-looking areas of space are actually so dense with gas and dust that even Webb cannot see through them. These thick clouds are the raw material of future stars and a cocoon for those still too young to shine.
The high resolution and mid-infrared sensitivity of Webb’s MIRI (Mid-Infrared Instrument) revealed this region in unprecedented detail, including glowing cosmic dust heated by very young massive stars. The reddest area on the right half of MIRI’s image, known as Sagittarius B2 North, is one of the most molecularly rich regions known, but astronomers have never seen it with such clarity. (Note: North is to the right in these Webb images.)
The difference longer wavelengths of light make, even within the infrared spectrum, are stark when comparing the images from Webb’s MIRI and NIRCam (Near-Infrared Camera) instruments. Glowing gas and dust appear dramatically in mid-infrared light, while all but the brightest stars disappear from view.
In contrast to MIRI, colorful stars steal the show in Webb’s NIRCam image, punctuated occasionally by bright clouds of gas and dust. Further research into these stars will reveal details of their masses and ages, which will help astronomers better understand the process of star formation in this dense, active galactic center region. Has it been going on for millions of years? Or has some unknown process triggered it only recently?
Astronomers hope Webb will shed light on why star formation in the galactic center is so disproportionately low. Though the region is stocked with plenty of gaseous raw material, on the whole it is not nearly as productive as Sagittarius B2. While Sagittarius B2 has only 10 percent of the galactic center’s gas, it produces 50 percent of its stars.
“Humans have been studying the stars for thousands of years, and there is still a lot to understand,” said Nazar Budaiev, a graduate student at the University of Florida and the co-principal investigator of the study. “For everything new Webb is showing us, there are also new mysteries to explore, and it’s exciting to be a part of that ongoing discovery.”
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
To learn more about Webb, visit:
Read more: NASA’s Webb Reveals New Features in Heart of Milky Way
Explore: ViewSpace interactive image tour of the center of the Milky Way
Explore: ViewSpace interactive views of the Eagle Nebula in different forms of light
Read more: Webb’s Star Formation Discoveries
Read more: Star formation in the Cat’s Paw Nebula
See what different wavelengths of infrared light reveal and conceal. Near-infrared light, which is nearest to visible red, comes from some gas and an abundance of colorful stars. The longer wavelengths of mid-infrared light are emitted by warm dust and only the brightest stars….
Laura Betz
NASA’s Goddard Space Flight Center
Greenbelt, Maryland
laura.e.betz@nasa.gov
Leah Ramsay
Space Telescope Science Institute
Baltimore, Maryland
Christine Pulliam
Space Telescope Science Institute
Baltimore, Maryland
2 min read
This NASA/ESA Hubble Space Telescope image reveals new details in Messier 82 (M82), home to brilliant stars whose light is shaded by sculptural clouds made of clumps and streaks of dust and gas. This image features the star-powered heart of the galaxy, located just 12 million light-years away in the constellation Ursa Major (the Great Bear). Popularly known as the Cigar Galaxy, M82 is considered a nearby galaxy.
It’s no surprise that M82 is packed with stars. The galaxy forms stars 10 times faster than the Milky Way. Astronomers call it a starburst galaxy. The intense starbirth period that grips this galaxy gave rise to super star clusters in the galaxy’s heart. Each of these super star clusters holds hundreds of thousands of stars and is more luminous than a typical star cluster. Researchers used Hubble to home in on these massive clusters and reveal how they form and evolve.
Hubble’s previous views of the galaxy captured ultraviolet and visible light in 2012 and near-infrared and visible light in 2006 to celebrate Hubble’s 16th anniversary. NASA’s Chandra X-ray Observatory and Spitzer Space Telescope also imaged this starburst galaxy. Combining the visible and near-infrared light Hubble data with Chandra’s x-ray and Spitzer’s deeper infrared view provides a detailed look at the galaxy’s stars, along with the dust and gas from which stars form. More recently the NASA/ESA/CSA James Webb Space Telescope turned its eye toward the galaxy, producing infrared images in 2024 and earlier this year. These multiple views at different wavelengths of light provide us with a more accurate and complete picture of this galaxy so that we can better understand its environment. Each of these NASA observatories delivers unique and complementary information about the galaxy’s physical processes. Combining their data yields insights that enhance our understanding in a way that no single observatory could accomplish alone. This image features something not seen in previously released Hubble images of the galaxy: data from the High Resolution Channel of the Advanced Camera for Surveys.
Media Contact:
Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight Center, Greenbelt, MD
A black hole is growing at one of the fastest rates ever recorded, according to a team of astronomers. This discovery from NASA’s Chandra X-ray Observatory may help explain how some black holes can reach enormous masses relatively quickly after the big bang.
The black hole weighs about a billion times the mass of the Sun and is located about 12.8 billion light-years from Earth, meaning that astronomers are seeing it only 920 million years after the universe began. It is producing more X-rays than any other black hole seen in the first billion years of the universe.
The black hole is powering what scientists call a quasar, an extremely bright object that outshines entire galaxies. The power source of this glowing monster is large amounts of matter funneling around and entering the black hole.
While the same team discovered it two years ago, it took observations from Chandra in 2023 to discover what sets this quasar, RACS J0320-35, apart. The X-ray data reveal that this black hole appears to be growing at a rate that exceeds the normal limit for these objects.
“It was a bit shocking to see this black hole growing by leaps and bounds,” said Luca Ighina of the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts, who led the study.
When matter is pulled toward a black hole it is heated and produces intense radiation over a broad spectrum, including X-rays and optical light. This radiation creates pressure on the infalling material. When the rate of infalling matter reaches a critical value, the radiation pressure balances the black hole’s gravity, and matter cannot normally fall inwards any more rapidly. That maximum is referred to as the Eddington limit.
Scientists think that black holes growing more slowly than the Eddington limit need to be born with masses of about 10,000 Suns or more so they can reach a billion solar masses within a billion years after the big bang — as has been observed in RACS J0320-35. A black hole with such a high birth mass could directly result from an exotic process: the collapse of a huge cloud of dense gas containing unusually low amounts of elements heavier than helium, conditions that may be extremely rare.
If RACS J0320-35 is indeed growing at a high rate — estimated at 2.4 times the Eddington limit — and has done so for a sustained amount of time, its black hole could have started out in a more conventional way, with a mass less than a hundred Suns, caused by the implosion of a massive star.
“By knowing the mass of the black hole and working out how quickly it’s growing, we’re able to work backward to estimate how massive it could have been at birth,” said co-author Alberto Moretti of INAF-Osservatorio Astronomico di Brera in Italy. “With this calculation we can now test different ideas on how black holes are born.”
To figure out how fast this black hole is growing (between 300 and 3,000 Suns per year), the researchers compared theoretical models with the X-ray signature, or spectrum, from Chandra, which gives the amounts of X-rays at different energies. They found the Chandra spectrum closely matched what they expected from models of a black hole growing faster than the Eddington limit. Data from optical and infrared light also supports the interpretation that this black hole is packing on weight faster than the Eddington limit allows.
“How did the universe create the first generation of black holes?” said co-author Thomas of Connor, also of the Center for Astrophysics. “This remains one of the biggest questions in astrophysics and this one object is helping us chase down the answer.”
Another scientific mystery addressed by this result concerns the cause of jets of particles that move away from some black holes at close to the speed of light, as seen in RACS J0320-35. Jets like this are rare for quasars, which may mean that the rapid rate of growth of the black hole is somehow contributing to the creation of these jets.
The quasar was previously discovered as part of a radio telescope survey using the Australian Square Kilometer Array Pathfinder, combined with optical data from the Dark Energy Camera, an instrument mounted on the Victor M. Blanco 4-meter Telescope at the Cerro Tololo Inter-American Observatory in Chile. The U.S. National Science Foundation National Optical-Infrared Astronomy Research Laboratory’s Gemini-South Telescope on Cerro Pachon, Chile was used to obtain the accurate distance of RACS J0320-35.
A paper describing these results has been accepted for publication in The Astrophysical Journal and is available here.
NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, and flight operations from Burlington, Massachusetts.
Learn more about the Chandra X-ray Observatory and its mission here:
This release features a quasar located 12.8 billion light-years from Earth, presented as an artist’s illustration and an X-ray image from NASA’s Chandra X-ray Observatory.
In the artist’s illustration, the quasar, RACS J0320-35, sits at our upper left, filling the left side of the image. It resembles a spiraling, motion-blurred disk of orange, red, and yellow streaks. At the center of the disk, surrounded by a glowing, sparking, brilliant yellow light, is a black egg shape. This is a black hole, one of the fastest-growing black holes ever detected. The black hole is also shown in a small Chandra X-ray image inset at our upper right. In that depiction, the black hole appears as a white dot with an outer ring of neon purple.
The artist’s illustration also highlights a jet of particles blasting away from the black hole at the center of the quasar. The streaked silver beam starts at the core of the distant quasar, near our upper left, and shoots down toward our lower right. The blurry beam of energetic particles appears to widen as it draws closer and exits the image.
Megan Watzke
Chandra X-ray Center
Cambridge, Mass.
617-496-7998
mwatzke@cfa.harvard.edu
Corinne Beckinger
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
corinne.m.beckinger@nasa.gov
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