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Webb images young, giant exoplanets in HR 8799, detects carbon dioxide

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This image shows the planetary system HR 8799. The image background is black. At the centre of the image, there is a symbol representing a star labeled HR 8799. This star blocks the light from the host star. There are four exoplanets, which look like fuzzy dots, pictured in the image surrounding the star. Furthest from the star is a fuzzy, faint blue dot, labeled b, at the 10 o’clock position. At the one o’clock position, second furthest from the star is a blueish-white fuzzy dot labeled c. Just below that is an orange dot labeled e. At the four o’clock position, still nearby the star, is another fuzzy white dot labeled d.

Webb images young, giant exoplanets in HR 8799, detects carbon dioxide

Findings suggest giant exoplanets in HR 8799 system likely formed like Jupiter and Saturn.

The NASA/ESA/CSA James Webb Space Telescope has captured direct images of multiple gas giant planets within an iconic planetary system. HR 8799, a young system 130 light-years away, has long been a key target for planet formation studies.

This image shows the planetary system HR 8799. The image background is black. At the centre of the image, there is a symbol representing a star labeled HR 8799. This star blocks the light from the host star. There are four exoplanets, which look like fuzzy dots, pictured in the image surrounding the star. Furthest from the star is a fuzzy, faint blue dot, labeled b, at the 10 o’clock position. At the one o’clock position, second furthest from the star is a blueish-white fuzzy dot labeled c. Just below that is an orange dot labeled e. At the four o’clock position, still nearby the star, is another fuzzy white dot labeled d.
The NASA/ESA/CSA James Webb Space Telescope has provided the clearest look yet at the iconic multi-planet system HR 8799. The observations detected carbon dioxide in each of the planets, which provides strong evidence that the system’s four giant planets formed much like Jupiter and Saturn, by slowly building solid cores that attract gas from within a protoplanetary disk. Colours are applied to filters from Webb’s NIRCam (Near-Infrared Camera), revealing their intrinsic differences. A star symbol marks the location of the host star HR 8799, whose light has been blocked by a coronagraph. The colours in this image, which represent different wavelengths captured by Webb’s NIRCam, tell researchers about the temperatures and composition of the planets. HR 8799 b, which orbits around 10.1 billion kilometres from the star, is the coldest of the bunch, and the richest in carbon dioxide. HR 8799 e orbits 2.4 billion kilometres from its star, and likely formed closer to the host star, where there were stronger variations in the composition of material. In this image, the colour blue is assigned to 4.1 micron light, green to 4.3 micron light, and red to the 4.6 micron light. Credit: NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI)

The observations indicate that the well-studied planets of HR 8799 are rich in carbon dioxide gas. This provides strong evidence that the system’s four giant planets formed much like Jupiter and Saturn, by slowly building solid cores that attract gas from within a protoplanetary disk.

The results also confirm that Webb can infer the chemistry of exoplanet atmospheres through imaging. This technique complements Webb’s powerful spectroscopic instruments, which resolve the atmospheric composition.

“By spotting these strong carbon dioxide features, we have shown there is a sizable fraction of heavier elements, like carbon, oxygen, and iron, in these planets’ atmospheres,” said William Balmer, of Johns Hopkins University in Baltimore. “Given what we know about the star they orbit, that likely indicates they formed via core accretion, which is an exciting conclusion for planets that we can directly see.”

Graphic titled “Exoplanet HR 8799 e: Carbon Dioxide in Gas Giant Exoplanet” has three data points with error bars and a best-fit model for low metal content and high metal content on a graph of Amount of Light from the Planet on the y-axis versus Wavelength of Light in microns on x-axis. Y-axis ranges from less light at bottom to more light at top. X-axis ranges from 3.6 to 5.0 microns. Webb NIRCam data consists of 3 points, plotted in red, with white error bars above and below each point. The best-fit models are jagged blue and yellow lines with several broad peaks and valleys. Two features are labeled with vertical columns. From 4.3 microns to nearly 4.4 microns, a green column is labeled Carbon Dioxide CO2. From nearly 4.4 microns to nearly 4.8 microns, a red column is labeled Carbon Monoxoide CO2.
This graph shows a spectrum of one of the planets in the HR 8799 system, HR 8799 e, which displays the amounts of near-infrared light detected from the planet by Webb at different wavelengths.
The blue and yellow lines are a best-fit model for an atmosphere that would be either low or high in metals heavier than helium, including carbon, also known as metallicity. The Webb data is consistent with a high metallicity planet. Spectral fingerprints of carbon dioxide and carbon monoxide appear in data collected by Webb’s NIRCam (Near-Infrared Camera). Credit: NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI)

Balmer is the lead author of the study announcing the results published today in The Astrophysical Journal. Balmer and his team’s analysis also includes Webb’s observation of a system 97 light-years away called 51 Eridani.

HR 8799 is a young system about 30 million years old, a fraction of our solar system’s 4.6 billion years. Still hot from their tumultuous formation, the planets within HR 8799 emit large amounts of infrared light that give scientists valuable data on how they formed.

Giant planets can take shape in two ways: by slowly building solid cores with heavier elements that attract gas, just like the giants in our solar system, or when particles of gas rapidly coalesce into massive objects from a young star’s cooling disk, which is made mostly of the same kind of material as the star. Knowing which formation model is more common can give scientists clues to distinguish between the types of planets they find in other systems.

“Our hope with this kind of research is to understand our own solar system, life, and ourselves in comparison to other exoplanetary systems, so we can contextualize our existence,” Balmer said. “We want to take pictures of other solar systems and see how they’re similar or different when compared to ours. From there, we can try to get a sense of how weird our solar system really is—or how normal.”

Of the nearly 6,000 exoplanets discovered, few have been directly imaged, as even giant planets are many thousands of times fainter than their stars. The images of HR 8799 and 51 Eridani were made possible by Webb’s NIRCam (Near-Infrared Camera) coronagraph, which blocks light from bright stars to reveal otherwise hidden worlds.

This image shows the exoplanet 51 Eri b. The image is mostly black, with very faint residual red dots apparent in the central region of the image. At the centre of the image, there is a symbol representing a star labeled 51 Eri. This star blocks the light from the host star. To the left of the circle is a fuzzy bright red circle, which is the exoplanet, labeled b.
The NASA/ESA/CSA James Webb Space Telescope’s NIRCam (Near-Infrared Camera) captured this image of Eridani 51 b, a cool, young exoplanet that orbits 17.7 billion kilometres from its star. Its distance is equivalent to a location between the orbits of Neptune and Saturn in our solar system. The observations detected the planet is rich in carbon dioxide, providing strong evidence that the planet formed much like Jupiter and Saturn, by slowly building a solid core that attracted gas from within a protoplanetary disk.
The 51 Eridani system is 96 light-years from Earth. This image includes filters representing 4.1-micron light as red. Credit: NASA, ESA, CSA, STScI, W. Balmer (JHU), L. Pueyo (STScI), M. Perrin (STScI)

This technology allowed the team to look for infrared light emitted by the planets in wavelengths that are absorbed by specific gases. The team found that the four HR 8799 planets contain more heavy elements than previously thought.

“Webb’s unique capabilities are allowing us to explore the wide diversity of these directly-imaged planets for the first time. This gives us important clues as to how such planetary systems have formed.” said Emily Rickman of the European Space Agency, a co-author of the study. “These new observations reiterate how valuable the HR 8799 multi-planet system is as a stepping stone to understand the formation of exoplanetary systems and of our own Solar System.”

The team is paving the way for more detailed observations to determine whether objects they see orbiting other stars are truly giant planets or objects such as brown dwarfs, which form like stars but don’t accumulate enough mass to ignite nuclear fusion.

“We have other lines of evidence that hint at these four HR 8799 planets forming using this bottom-up approach,” said Laurent Pueyo, an astronomer at the Space Telescope Science Institute in Baltimore, who co-led the work. “How common is this for planets we can directly image? We don’t know yet, but we’re proposing more Webb observations to answer that question.”

“We knew Webb could measure colours of the outer planets in directly imaged systems,” added Rémi Soummer, director of STScI’s Russell B. Makidon Optics Lab and former lead for Webb coronagraph operations. “We have been waiting for 10 years to confirm that our finely tuned operations of the telescope would also allow us to access the inner planets. Now the results are in and we can do interesting science with it.”

The NIRCam observations of HR 8799 and 51 Eridani were conducted as part of Guaranteed Time Observations programmes 1194 and 1412 respectively.

Press release from ESA Webb.

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Webb wows with incredible detail in actively forming star system, Lynds 483 (L483)

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At the centre is a thin vertical cloud known as Lynds 483 (L483) that is roughly shaped like an hourglass with irregular edges. The lower lobe is slightly cut off. The top lobe is seen in full, petering out at the top.

Webb wows with incredible detail in actively forming star system, Lynds 483 (L483)

High-resolution near-infrared light captured by the NASA/ESA/CSA James Webb Space Telescope shows extraordinary new detail and structure in Lynds 483 (L483). Two actively forming stars are responsible for the shimmering ejections of gas and dust that gleam in orange, blue, and purple in this representative colour image.

At the centre is a thin vertical cloud known as Lynds 483 (L483) that is roughly shaped like an hourglass with irregular edges. The lower lobe is slightly cut off. The top lobe is seen in full, petering out at the top.
Shimmering ejections emitted by two actively forming stars make up Lynds 483 (L483). High-resolution near-infrared light captured by the NASA/ESA/CSA James Webb Space Telescope shows incredible new detail and structure within these lobes, including asymmetrical lines that appear to run into one another. L483 is 650 light-years away in the constellation Serpens.
Credit: NASA, ESA, CSA, STScI

Over tens of thousands of years, the central protostars [1] have periodically ejected some of the gas and dust, spewing it out as tight, fast jets and slightly slower outflows that “trip” across space. When more recent ejections hit older ones, the material can crumple and twirl based on the densities of what is colliding. Over time, chemical reactions within these ejections and the surrounding cloud have produced a range of molecules, like carbon monoxide, methanol, and several other organic compounds.

Dust-encased stars

The two protostars responsible for this scene are at the centre of the hourglass shape, in an opaque horizontal disk of cold gas and dust that fits within a single pixel. Much farther out, above and below the flattened disk where dust is thinner, the bright light from the stars shines through the gas and dust, forming large semi-transparent orange cones.

It’s equally important to notice where the stars’ light is blocked — look for the exceptionally dark, wide V-shapes offset by 90 degrees from the orange cones. These areas may look like there is no material, but it’s actually where the surrounding dust is the densest, and little starlight penetrates it. If you look carefully at these areas, Webb’s sensitive NIRCam (Near-Infrared Camera) has picked up distant stars as muted orange pinpoints behind this dust. Where the view is free of obscuring dust, stars shine brightly in white and blue.

Unraveling the stars’ ejections

Some of the stars’ jets and outflows have wound up twisted or warped. To find examples, look toward the top right edge where there’s a prominent orange arc. This is a shock front, where the stars’ ejections were slowed by existing, denser material.

Now, look a little lower, where orange meets pink. Here, the material looks like a tangled mess. These are new, incredibly fine details Webb has revealed, and will require detailed study to explain.

Turn to the lower half. Here, the gas and dust appear thicker. Zoom in to find tiny light purple pillars. They point toward the central stars’ nonstop winds, and formed because the material within them is dense enough that it hasn’t yet been blown away. L483 is too large to fit in a single Webb snapshot, and this image was taken to fully capture the upper section and outflows, which is why the lower section is only partially shown.

All the symmetries and asymmetries in these clouds may eventually be explained as researchers reconstruct the history of the stars’ ejections, in part by updating models to produce the same effects. Astronomers will also eventually calculate how much material the stars have expelled, which molecules were created when material smashed together, and how dense each area is.

Millions of years from now, when the stars are finished forming, they may each be about the mass of our Sun. Their outflows will have cleared the area — sweeping away these semi-transparent ejections. All that may remain is a tiny disk of gas and dust where planets may eventually form.

L483 is named for American astronomer Beverly T. Lynds, who published extensive catalogues of “dark” and “bright” nebulae in the early 1960s. She did this by carefully examining photographic plates (which preceded film) of the first Palomar Observatory Sky Survey, accurately recording each object’s coordinates and characteristics. These catalogues provided astronomers with detailed maps of dense dust clouds where stars form — critical resources for the astronomical community decades before the first digital files became available and access to the internet was widespread.

In the centre is a thin vertical cloud known as Lynds 483 (L483) that is roughly shaped like an hourglass with irregular edges. At the top right is a scale bar labeled 0.1 light-years. The length of the scale bar is about one fifth of the total image. At the bottom left are compass arrows indicating the orientation of the image on the sky. The east arrow points toward 12 o’clock. The north arrow points in the 3 o’clock direction. Below the image is a colour key showing which NIRCam filters were used to create the image and which visible-light colour is assigned to each filter. From left to right: F115W and F200W are blue, F335M is green, F444W is yellow, F470N is red.
This image of protostar Lynds 483 (L483), captured by the NASA/ESA/CSA James Webb Space Telescope’s NIRCam (Near-Infrared Camera), shows compass arrows, scale bar, and colour key for reference. The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).
The scale bar is labelled in light-years, which is the distance that light travels in one Earth-year. (It takes 0.1 years for light to travel a distance equal to the length of the scale bar.) One light-year is equal to 9.46 trillion kilometres. This image shows invisible near-infrared wavelengths of light that have been translated into visible-light colours. The colour key shows which NIRCam filters were used when collecting the light. The colour of each filter name is the visible light colour used to represent the infrared light that passes through that filter.
Credit: NASA, ESA, CSA, STScI

Notes

[1] A protostar is a collection of interstellar gas and dust whose gravitational pull is causing it to collapse on itself and form a star.

Press release from ESA Webb.

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Webb exposes complex atmosphere of SIMP 0136, a starless super-Jupiter

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Illustration of a gas giant planet or brown dwarf on a background of distant stars.

Webb exposes complex atmosphere of SIMP 0136, a starless super-Jupiter

An international team of researchers has discovered that previously observed variations in brightness across a free-floating planetary-mass object known as SIMP 0136 must be the result of a complex combination of atmospheric factors, and cannot be explained by clouds alone.

Using the NASA/ESA/CSA James Webb Space Telescope to monitor a broad spectrum of infrared light emitted by SIMP 0136 over two full rotation periods, the team was able to detect variations in cloud layers, temperature, and carbon chemistry that were previously hidden from view. The results provide crucial insight into the three-dimensional complexity of gas giant atmospheres within and beyond our solar system.

Rapidly rotating, free-floating

SIMP 0136 is a rapidly rotating, free-floating object roughly 13 times the mass of Jupiter, located in the Milky Way just 20 light-years from Earth. Although it is not classified as a gas giant exoplanet — it doesn’t orbit a star and may instead be a brown dwarf — SIMP 0136 is an ideal target for exo-meteorology: It is the brightest object of its kind in the northern sky. Because it is isolated, it can be observed directly and with no fear of light contamination or variability caused by a host star. And its short rotation period of just 2.4 hours makes it possible to survey very efficiently.

Prior to the Webb observations, SIMP 0136 had been studied extensively using ground-based observatories, as well as and NASA’s Spitzer Space Telescope and the NASA/ESA Hubble Space Telescope.

“We already knew that it varies in brightness, and we were confident that there are patchy cloud layers that rotate in and out of view and evolve over time,” explained Allison McCarthy, doctoral student at Boston University and lead author on a study published today in The Astrophysical Journal Letters. “We also thought there could be temperature variations, chemical reactions, and possibly some effects of auroral activity affecting the brightness, but we weren’t sure.”

To figure it out, the team needed Webb’s ability to measure very precise changes in brightness over a broad range of wavelengths.

Charting thousands of infrared rainbows

Using NIRSpec (Near-Infrared Spectrograph), Webb captured thousands of individual 0.6- to 5.3-micron spectra — one every 1.8 seconds over more than three hours as the object completed one full rotation. This was immediately followed by an observation with MIRI (Mid-Infrared Instrument), which collected hundreds of measurements of 5- to 14-micron light — one every 19.2 seconds, over another rotation.

The result was hundreds of detailed light curves, each showing the change in brightness of a very precise wavelength (color) as different sides of the object rotated into view.

“To see the full spectrum of this object change over the course of minutes was incredible,” said principal investigator Johanna Vos, from Trinity College Dublin. “Until now, we only had a little slice of the near-infrared spectrum from Hubble, and a few brightness measurements from Spitzer.”

The team noticed almost immediately that there were several distinct light-curve shapes. At any given time, some wavelengths were growing brighter, while others were becoming dimmer or not changing much at all. A number of different factors must be affecting the brightness variations.

“Imagine watching Earth from far away. If you were to look at each color separately, you would see different patterns that tell you something about its surface and atmosphere, even if you couldn’t make out the individual features,” explained co-author Philip Muirhead, also from Boston University. “Blue would increase as oceans rotate into view. Changes in brown and green would tell you something about soil and vegetation.”

Illustration of a gas giant planet or brown dwarf on a background of distant stars.
This artist’s concept shows what the isolated planetary-mass object SIMP 0136 could look like based on recent observations from the NASA/ESA/CSA James Webb Space Telescope.
SIMP 0136 has a mass about 13 times that of Jupiter. Although it is thought to have the structure and composition of a gas giant, it is not technically classified as an exoplanet because it doesn’t orbit its own star.
The colors shown in the illustration represent near-infrared light, which is invisible to human eyes. SIMP 0136 is relatively warm — about 825 degrees Celsius or 1,100 kelvins — but is not hot enough to give off enough visible light to see from Earth, and is not illuminated by a host star. The bluish glow near the poles represents auroral energy (light given off by electrons spiraling in a magnetic field) which has been detected at radio wavelengths.
Researchers used NIRSpec (Near-infrared Spectrograph) and MIRI (Mid-Infrared Instrument) to monitor the brightness of SIMP 0136 over two full rotations in July 2023. By analyzing the change in brightness of different wavelengths over time, researchers were able to detect variability in cloud cover at different depths, temperature variations in the high atmosphere, and changes in carbon chemistry as different sides of the object rotated in and out of view.
SIMP 0136 is located within the Milky Way, about 20 light-years from Earth, in the constellation Pisces. It is the brightest isolated planet or brown dwarf visible from the Northern Hemisphere, and is thought to be about 200 million years old. This illustration is based on spectroscopic observations. Webb has not captured a direct image of the object.
Credit: NASA, ESA, CSA, J. Olmsted (STScI)

Patchy clouds, hot spots, and carbon chemistry

To figure out what could be causing the variability on SIMP 0136, the team used atmospheric models to show where in the atmosphere each wavelength of light was originating.

“Different wavelengths provide information about different depths in the atmosphere,” explained McCarthy. “We started to realize that the wavelengths that had the most similar light-curve shapes also probed the same depths, which reinforced this idea that they must be caused by the same mechanism.”

One group of wavelengths, for example, originates deep in the atmosphere where there could be patchy clouds made of iron particles. A second group comes from higher clouds thought to be made of tiny grains of silicate minerals. The variations in both of these light curves are related to patchiness of the cloud layers.

A third group of wavelengths originates at very high altitude, far above the clouds, and seems to track temperature. Bright “hot spots” could be related to auroras that were previously detected at radio wavelengths, or to upwelling of hot gas from deeper in the atmosphere.

Some of the light curves cannot be explained by either clouds or temperature, but instead show variations related to atmospheric carbon chemistry. There could be pockets of carbon monoxide and carbon dioxide rotating in and out of view, or chemical reactions causing the atmosphere to change.

“We haven’t really figured out the chemistry part of the puzzle yet,” said Vos. “But these results are really exciting because they are showing us that the abundances of molecules like methane and carbon dioxide could change from place to place and over time. If we are looking at an exoplanet and can get only one measurement, we need to consider that it might not be representative of the entire planet.”

This research was conducted as part of Webb’s General Observer (GO) Program 3548.

Bibliographic information:

Allison M. McCarthy et al 2025, ApJL 981 L22, DOI: 10.3847/2041-8213/ad9eaf

The graphic has two parts. On the left are light curves showing the change in brightness of three sets of near-infrared wavelengths over time. On the right is a cross-section of the object’s atmosphere, showing the altitude that each set of wavelengths originates and their relationship to cloud layers or temperature.
These light curves show the change in brightness of three different sets of wavelengths (colors) of near-infrared light coming from the isolated planetary-mass object SIMP 0136 as it rotated. The light was captured by Webb’s NIRSpec (Near-Infrared Spectrograph), which collected a total of 5,726 spectra — one every 1.8 seconds — over the course of about 3 hours on 23 July 2023 (SIMP 0136 completes one rotation every 2.4 hours).
By comparing these light curves to models, researchers were able to show that each set of wavelengths probes different depths (pressures) in the atmosphere.
The curve shown in red tracks the brightness of 0.9- to 1.4-micron light thought to originate deep in the atmosphere at a pressure of about 10 bars (about 10 times the air pressure at sea level on Earth), within clouds made of iron particles. The curve shown in yellow tracks the brightness of 1.4- to 2.3-micron light from a pressure of about 1 bar within higher clouds made of tiny grains of silicate minerals. The variations in brightness shown by these two curves is related to patchiness of the cloud layers, which emit some wavelengths of light and absorb others.
The curve shown in blue tracks the brightness of 3.3- to 3.6-micron light that originates high above the clouds at a pressure of about 0.1 bars. Changes in brightness of these wavelengths are related to variations in temperature around the object. Bright “hot spots” could be related to auroras that have been detected at radio wavelengths, or to upwelling of hot gas from deeper in the atmosphere.
The differences in shape of these three light curves show that there are complex variations in SIMP 0136’s atmosphere with depth as well as longitude. If the atmosphere varied around the object in the same way at all depths, the light curves would have similar patterns. If it varied with depth, but not longitude, the light curves would be straight, flat lines.
Note this graph shows the relative change in brightness for each given set of wavelengths over time, not the difference in absolute brightness between the different sets. At any given time, there is more light coming from the deep atmosphere (red light curve) than from the upper atmosphere (blue light curve).
SIMP 0136 is located within the Milky Way, about 20 light-years from Earth, in the constellation Pisces. It is the brightest isolated planet or brown dwarf visible from the Northern Hemisphere, and is thought to be about 200 million years old. The artist’s concepts are based on spectroscopic observations. Webb has not captured a direct image of the object.
Credit: NASA, ESA, CSA, J. Olmsted (STScI)

Press release from ESA Webb.

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NASA’s Asteroid Bennu Sample Reveals Mix of Life’s Ingredients

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In this video frame, Jason Dworkin holds up a vial that contains part of the sample from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) mission in 2023. Dworkin is the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Credit: NASA/James Tralie

NASA’s Asteroid Bennu Sample Reveals Mix of Life’s Ingredients

Studies of rock and dust from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security–Regolith Explorer) spacecraft have revealed molecules that, on our planet, are key to life, as well as a history of saltwater that could have served as the “broth” for these compounds to interact and combine.

The findings do not show evidence for life itself, but they do suggest the conditions necessary for the emergence of life were widespread across the early solar system, increasing the odds life could have formed on other planets and moons.

“NASA’s OSIRIS-REx mission already is rewriting the textbook on what we understand about the beginnings of our solar system,” said Nicky Fox, associate administrator, Science Mission Directorate at NASA Headquarters in Washington. “Asteroids provide a time capsule into our home planet’s history, and Bennu’s samples are pivotal in our understanding of what ingredients in our solar system existed before life started on Earth.”

In research papers published Wednesday in the journals Nature and Nature Astronomy, scientists from NASA and other institutions shared results of the first in-depth analyses of the minerals and molecules in the Bennu samples, which OSIRIS-REx delivered to Earth in 2023.

Detailed in the Nature Astronomy paper, among the most compelling detections were amino acids – 14 of the 20 that life on Earth uses to make proteins – and all five nucleobases that life on Earth uses to store and transmit genetic instructions in more complex terrestrial biomolecules, such as DNA and RNA, including how to arrange amino acids into proteins.

Scientists also described exceptionally high abundances of ammonia in the Bennu samples. Ammonia is important to biology because it can react with formaldehyde, which also was detected in the samples, to form complex molecules, such as amino acids – given the right conditions. When amino acids link up into long chains, they make proteins, which go on to power nearly every biological function.

These building blocks for life detected in the Bennu samples have been found before in extraterrestrial rocks. However, identifying them in a pristine sample collected in space supports the idea that objects that formed far from the Sun could have been an important source of the raw precursor ingredients for life throughout the solar system.

“The clues we’re looking for are so minuscule and so easily destroyed or altered from exposure to Earth’s environment,” said Danny Glavin, a senior sample scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and co-lead author of the Nature Astronomy paper. “That’s why some of these new discoveries would not be possible without a sample-return mission, meticulous contamination-control measures, and careful curation and storage of this precious material from Bennu.”

While Glavin’s team analyzed the Bennu samples for hints of life-related compounds, their colleagues, led by Tim McCoy, curator of meteorites at the Smithsonian’s National Museum of Natural History in Washington, and Sara Russell, cosmic mineralogist at the Natural History Museum in London, looked for clues to the environment these molecules would have formed. Reporting in the journal Nature, scientists further describe evidence of an ancient environment well-suited to kickstart the chemistry of life.

Ranging from calcite to halite and sylvite, scientists identified traces of 11 minerals in the Bennu sample that form as water containing dissolved salts evaporates over long periods of time, leaving behind the salts as solid crystals.

Similar brines have been detected or suggested across the solar system, including at the dwarf planet Ceres and Saturn’s moon Enceladus.

Although scientists have previously detected several evaporites in meteorites that fall to Earth’s surface, they have never seen a complete set that preserves an evaporation process that could have lasted thousands of years or more. Some minerals found in Bennu, such as trona, were discovered for the first time in extraterrestrial samples.

“These papers really go hand in hand in trying to explain how life’s ingredients actually came together to make what we see on this aqueously altered asteroid,” said McCoy.

For all the answers the Bennu sample has provided, several questions remain. Many amino acids can be created in two mirror-image versions, like a pair of left and right hands. Life on Earth almost exclusively produces the left-handed variety, but the Bennu samples contain an equal mixture of both. This means that on early Earth, amino acids may have started out in an equal mixture, as well. The reason life “turned left” instead of right remains a mystery.

“OSIRIS-REx has been a highly successful mission,” said Jason Dworkin, OSIRIS-REx project scientist at NASA Goddard and co-lead author on the Nature Astronomy paper. “Data from OSIRIS-REx adds major brushstrokes to a picture of a solar system teeming with the potential for life. Why we, so far, only see life on Earth and not elsewhere, that’s the truly tantalizing question.”

NASA Goddard provided overall mission management, systems engineering, and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator. The university leads the science team and the mission’s science observation planning and data processing. Lockheed Martin Space in Littleton, Colorado, built the spacecraft and provided flight operations. NASA Goddard and KinetX Aerospace were responsible for navigating the OSIRIS-REx spacecraft. Curation for OSIRIS-REx takes place at NASA’s Johnson Space Center in Houston. International partnerships on this mission include the OSIRIS-REx Laser Altimeter instrument from CSA (Canadian Space Agency) and asteroid sample science collaboration with JAXA’s (Japan Aerospace Exploration Agency) Hayabusa2 mission. OSIRIS-REx is the third mission in NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.

Bibliographic information:

Glavin, D.P., Dworkin, J.P., Alexander, C.M.O. et al. Abundant ammonia and nitrogen-rich soluble organic matter in samples from asteroid (101955) Bennu, Nat Astron (2025), DOI: https://doi.org/10.1038/s41550-024-02472-9

In this video frame, Jason Dworkin holds up a vial that contains part of the sample from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) mission in 2023. Dworkin is the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.Credit: NASA/James Tralie
In this video frame, Jason Dworkin holds up a vial that contains part of the sample from asteroid Bennu delivered to Earth by NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security – Regolith Explorer) mission in 2023. Dworkin is the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
Credit: NASA/James Tralie

Press release from NASA

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Hubble traces hidden history of the Andromeda Galaxy

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The Andromeda galaxy, a spiral galaxy, spreads across the image. It is tilted nearly edge-on to our line of sight so that it appears very oval. The borders of the galaxy are jagged because the image is a mosaic of smaller, square images against a black background. The outer edges of the galaxy are blue, while the inner two-thirds is yellowish with a bright, central core. Dark, dusty filamentary clouds wrap around the outer half of the galaxy’s disk. At 10 o’clock, a smaller dwarf elliptical galaxy forms a fuzzy, yellow blob. Hubble’s sharp vision distinguishes about 200 million stars within the image.

Hubble traces hidden history of the Andromeda Galaxy

Panorama of nearest galaxy unveils hundreds of millions of stars

The largest photomosaic of the Andromeda galaxy, assembled from NASA/ESA Hubble Space Telescope observations, has been unveiled. It took more than 10 years to collect data for this colorful portrait of our neighboring galaxy and was created from more than 600 snapshots. This stunning, colorful mosaic captures the glow of 200 million stars, and is spread across roughly 2.5 billion pixels.

In the years following the launch of the NASA/ESA Hubble Space Telescope, astronomers have tallied over 1 trillion galaxies in the universe. But only one galaxy stands out as the most important nearby stellar island to our Milky Way: the magnificent Andromeda galaxy (Messier 31). It can be seen with the naked eye on a very clear autumn night as a faint cigar-shaped object roughly the apparent angular diameter of our Moon.

A century ago, Edwin Hubble first established that this so-called “spiral nebula” was actually far outside our own Milky Way galaxy — at a distance of approximately 2.5 million light-years, or roughly 25 Milky Way diameters. Prior to that, astronomers had long thought that the Milky Way encompassed the entire universe. Overnight, Hubble’s discovery turned cosmology upside down by unveiling an infinitely grander universe.

Now, a century later, the space telescope named for Hubble has accomplished the most comprehensive survey of this enticing empire of stars. The Hubble telescope is yielding new clues to the evolutionary history of Andromeda, and it looks markedly different from the Milky Way’s history.

Without Andromeda as a proxy for spiral galaxies in the universe at large, astronomers would know much less about the structure and evolution of our own Milky Way. That’s because we are embedded inside the Milky Way.

Hubble’s sharp imaging capabilities can resolve more than 200 million stars in the Andromeda galaxy, detecting only stars brighter than our Sun. They look like grains of sand across the beach. But that’s just the tip of the iceberg. Andromeda’s total population is estimated to be 1 trillion stars, with many less massive stars falling below Hubble’s sensitivity limit.

Photographing Andromeda was a herculean task because the galaxy is a much bigger target on the sky than the galaxies Hubble routinely observes, which are often billions of light-years away. The full mosaic was carried out under two Hubble observing programs. In total it required over 1,000 Hubble orbits, spanning more than a decade.

The Andromeda galaxy is shown at the top of the visual. It is a spiral galaxy that spreads across the image. It is tilted nearly edge-on to our line of sight so that it appears very oval. The borders of the galaxy are jagged because the image is a mosaic of smaller, square images against a black background. The outer edges of the galaxy are blue, while the inner two-thirds is yellowish with a bright, central core. Five callout squares highlight interesting features of the galaxy
This is the largest photomosaic ever made by the Hubble Space Telescope. The target is the vast Andromeda galaxy that is only 2.5 million light-years from Earth, making it the nearest galaxy to our own Milky Way. Andromeda is seen almost edge-on, tilted by 77 degrees relative to Earth’s view. The galaxy is so large that the mosaic is assembled from approximately 600 separate fields of view taken over 10 years of Hubble observing. The mosaic image is made up of at least 2.5 billion pixels. Hubble resolves an estimated 200 million stars that are hotter than our sun, but still a fraction of the galaxy’s total estimated stellar population.
Interesting regions include:
Clusters of bright blue stars embedded within the galaxy, background galaxies seen much farther away, and photo-bombing by a couple bright foreground stars that are actually inside our Milky Way;
NGC 206 the most conspicuous star cloud in Andromeda;
A young cluster of blue newborn stars;
The satellite galaxy M32, that may be the residual core of a galaxy that once collided with Andromeda;
Dark dust lanes across myriad stars.
Credit: NASA, ESA, B. Williams (U. of Washington)

This panorama started with the Panchromatic Hubble Andromeda Treasury (PHAT) program about a decade ago. Images were obtained at near-ultraviolet, visible, and near-infrared wavelengths using the Advanced Camera for Surveys and the Wide Field Camera aboard Hubble to photograph the northern half of Andromeda.

This program was followed up by the Panchromatic Hubble Andromeda Southern Treasury (PHAST), which added images of approximately 100 million stars in the southern half of Andromeda. This region is structurally unique and more sensitive to the galaxy’s merger history than the northern disk mapped by the PHAT survey.

The combined programs collectively cover the entire disk of Andromeda, which is seen almost edge-on — tilted by 77 degrees relative to Earth’s view. The galaxy is so large that the mosaic is assembled from approximately 600 separate fields of view. The mosaic image is made up of at least 2.5 billion pixels.

The complementary Hubble survey programs provide information about the age, heavy-element abundance and stellar masses inside Andromeda. This will allow astronomers to distinguish between competing scenarios where Andromeda merged with one or more galaxies. Hubble’s detailed measurements constrain models of Andromeda’s merger history and disk evolution.

Though the Milky Way and Andromeda formed presumably around the same time many billions of years ago, observational evidence shows that they have very different evolutionary histories, despite growing up in the same cosmological neighborhood. Andromeda seems to be more highly populated with younger stars and unusual features like coherent streams of stars, say researchers. This implies it has a more active recent star-formation and interaction history than the Milky Way.

A possible culprit is the compact satellite galaxy Messier 32, which resembles the stripped-down core of a once-spiral galaxy that may have interacted with Andromeda in the past. Computer simulations suggest that when a close encounter with another galaxy uses up all the available interstellar gas, star formation subsides.

Hubble’s new findings will support future observations by the NASA/ESA/CSA James Webb Space Telescope.

The Andromeda galaxy, a spiral galaxy, spreads across the image. It is tilted nearly edge-on to our line of sight so that it appears very oval. The borders of the galaxy are jagged because the image is a mosaic of smaller, square images against a black background. The outer edges of the galaxy are blue, while the inner two-thirds is yellowish with a bright, central core. Dark, dusty filamentary clouds wrap around the outer half of the galaxy’s disk. At 10 o’clock, a smaller dwarf elliptical galaxy forms a fuzzy, yellow blob. Hubble’s sharp vision distinguishes about 200 million stars within the image.
This the largest photomosaic ever assembled from NASA/ESA Hubble Space Telescope observations: it is a panoramic view of the neighboring Andromeda galaxy, located 2.5 million light-years away. It took over 10 years to make this vast and colorful portrait of the galaxy, requiring over 600 Hubble snapshots. The galaxy is so close to us, that in angular size it is six times the apparent diameter of the full Moon, and can be seen with the unaided eye. For Hubble’s pinpoint view, that’s a lot of celestial real estate to cover. This stunning, colorful mosaic captures the glow of 200 million stars. That’s still a fraction of Andromeda’s population. And the stars are spread across about 2.5 billion pixels. The detailed look at the resolved stars will help astronomers piece together the galaxy’s past history that includes mergers with smaller satellite galaxies.
Credit: NASA, ESA, B. Williams (University of Washington)

Press release from ESA Hubble

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Webb watches Wolf-Rayet 140: carbon-rich dust shells form, expand in star system

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A three-part graphic showing observations of Wolf-Rayet 140, two massive stars with 17 dust shells around them. An inset appears at right, showing a portion of the two observations matched up to show that the arced dust has moved.

Webb watches Wolf-Rayet 140: carbon-rich dust shells form, expand in star system

Astronomers using the NASA/ESA/CSA James Webb Space Telescope have identified two stars responsible for generating carbon-rich dust a mere 5000 light-years away in our own Milky Way galaxy. As the massive stars in Wolf-Rayet 140 swing past one another on their elongated orbits, their winds collide and produce the carbon-rich dust. For a few months every eight years, the stars form a new shell of dust that expands outward — and may eventually go on to become part of stars that form elsewhere in our galaxy.

Astronomers have long tried to track down how elements like carbon, which is essential for life, become widely distributed across the Universe. Now, the James Webb Space Telescope has examined one ongoing source of carbon-rich dust in our own Milky Way galaxy in greater detail: Wolf-Rayet 140 [1], a system of two massive stars that follow a tight, elongated orbit.

As they swing past one another (within the central white dot in the Webb images), the stellar winds from each star slam together, the material compresses, and carbon-rich dust forms. Webb’s latest observations show 17 dust shells shining in mid-infrared light that are expanding at regular intervals into the surrounding space.

“The telescope confirmed that these dust shells are real, and its data also showed that the dust shells are moving outward at consistent velocities, revealing visible changes over incredibly short periods of time,”

said Emma Lieb, the lead author of the new paper and a doctoral student at the University of Denver in Colorado.

Every shell is racing away from the stars at more than 2600 kilometres per second, almost 1% the speed of light. 

“We are used to thinking about events in space taking place slowly, over millions or billions of years,” added Jennifer Hoffman, a co-author and a professor at the University of Denver. “In this system, the observatory is showing that the dust shells are expanding from one year to the next.”

“Seeing the real-time movement of these shells between Webb’s observations that were taken only 13 months apart is truly remarkable,” said Olivia Jones, a co-author at the UK Astronomy Technology Centre, Edinburgh. “These new results are giving us a first glimpse of the potential role of such massive binaries as factories of dust in the Universe.”

Like clockwork, the stars’ winds generate dust for several months every eight years, as the pair make their closest approach during a wide, elongated orbit. Webb also shows where dust formation stops — look for the darker region at top left in both images.

The telescope’s mid-infrared images detected shells that have persisted for more than 130 years (older shells have dissipated enough that they are now too dim to detect). The researchers speculate that the stars will ultimately generate tens of thousands of dust shells over hundreds of thousands of years.

“Mid-infrared observations are absolutely crucial for this analysis, since the dust in this system is fairly cool. Near-infrared and visible-light observations would only show the shells that are closest to the star,” explained Ryan Lau, a co-author and astronomer at NSF NOIRLab in Tucson, Arizona, who led the initial research about this system. “With these incredible new details, the telescope is also allowing us to study exactly when the stars are forming dust — almost to the day.”

The distribution of the dust isn’t uniform. Though these differences aren’t obvious in Webb’s images, the team found that some of the dust has ‘piled up’, forming amorphous, delicate clouds that are as large as our entire Solar System. Many other individual dust particles float freely. Every speck is as small as one-hundredth the width of a human hair. Clumpy or not, all of the dust moves at the same speed and is carbon rich.

The future of this system

What will happen to these stars over millions or billions of years, after they have finished ‘spraying’ their surroundings with dust? The Wolf-Rayet star in this system is 10 times more massive than the Sun and nearing the end of its life. In its final ‘act’, this star will either explode as a supernova — possibly blasting away some or all of the dust shells — or collapse into a black hole, which would leave the dust shells intact.

Though no one can predict with any certainty what will happen, researchers are rooting for the black hole scenario.

“A major question in astronomy is, where does all the dust in the universe come from?” Lau said. “If carbon-rich dust like this survives, it could help us begin to answer that question.”

“We know carbon is necessary for the formation of rocky planets and solar systems like ours,” Hoffman added. “It’s exciting to get a glimpse into how binary star systems not only create carbon-rich dust, but also propel it into our galactic neighborhood.”

These results have been published in the Astrophysical Journal Letters and were presented in a press conference at the 245th meeting of the American Astronomical Society in National Harbor, Maryland.

Notes

[1] A Wolf-Rayet star is born with at least 25 times more mass than our Sun and is nearing the end of its life, when it will likely collapse directly to black hole, or explode as a supernova. Burning hotter than in its youth, a Wolf-Rayet star generates powerful winds that push huge amounts of gas into space. The Wolf-Rayet star in this particular pair may have shed more than half its original mass via this process.

 

Press release from ESA Webb.

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NIH officials assess threat of H5N1

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Photo of a wild bird. To the right is a colorized transmission electron micrograph of H5N1 virus particles (purple). H5N1 bird flu is widespread in wild birds worldwide, and in 2024 is causing a multistate outbreak in poultry and U.S. dairy cows. Bird photo by NIAID; micrograph, which has been repositioned and recolored by NIAID, is courtesy CDC. Picture Credits: NIAID and CDC

NIH officials assess threat of H5N1

Balancing enhanced vigilance and “business as usual”

 

Highly pathogenic H5N1 avian influenza A virus (HPAI H5N1) remains a low risk to the general public, and public health experts in the United States believe that available treatments and vaccines, as well as those in development, are sufficient to prevent severe disease. However, the National Institutes of Health (NIH) and its federal partners remain focused on monitoring the virus and evaluating changes, according to leading officials at the National Institute of Allergy and Infectious Diseases (NIAID), part of the NIH.

In a commentary published in the New England Journal of Medicine, NIAID Director Jeanne M. Marrazzo, M.D., M.P.H., and Michael G. Ison, M.D., M.S., chief of the Respiratory Diseases Branch in NIAID’s Division of Microbiology and Infectious Diseases, say people should find a balance between enhanced vigilance and “business as usual” with respect to HPAI H5N1.

Since 1996, HPAI H5N1 influenza viruses have circulated in at least 23 countries. In late 2021, HPAI H5N1 spread from Europe to North America causing sporadic infections among wild birds and poultry farms. In 2022, the virus spread to South America where it devastated birds and marine mammals. In March 2024, USDA scientists identified HPAI H5N1 in U.S. dairy cows, and it subsequently reached herds in 16 states. The virus has been detected in dairy herds in three states over the past 30 days, according to USDA/APHIS. In 2024, the virus has caused 66 confirmed and 7 probable cases of influenza in people in the U.S. and one case in Canada. These human cases have been caused by either the H5N1 type circulating in birds (D1.1) or the type circulating in dairy cows (B3.13).

Against this backdrop, Drs. Marrazzo and Ison say there are four keys to controlling the current outbreak. The first imperative is timely, effective collaborations among investigators in human and veterinary medicine, public health, health care, and occupational workers, such as dairy and poultry workers.

This involves cultivating trust not only between numerous entities, but with people seeking care for symptoms of concern, including conjunctivitis, the authors write. Fortunately, so far most U.S. cases of HPAI H5N1 have been mild and resolved on their own without the need for treatment.

Their second key is a focus on the Canadian HPAI H5N1 patient, who developed respiratory failure and required life-saving medical intervention and treatment before recovering. The authors write that mutations found in the virus in this patient highlight an urgent need for vigilant disease surveillance to identify and assess viral changes to evaluate the risk for person-to-person transmission. Effective surveillance, they say, requires that complete genomic sequencing data from animals and people are made rapidly and readily available.

Without information pertaining to where and when isolates were collected, the data cannot be linked phylogenetically to other reported sequences, limiting insight into how the virus is spreading, they write. These data would also provide opportunity for early detection of mutations that might portend avidity for human respiratory epithelium, which may require as little as one mutation in the virus.

Third, researchers must continue to develop and test medical countermeasures—such as vaccines and therapies that eliminate or alleviate disease—against H5N1 and other influenza viruses. Fortunately, current vaccine candidates neutralize the circulating strains, which so far are susceptible to antivirals that could mitigate transmission and severity of illness, they write.

Lastly, Drs. Marrazzo and Ison encourage people to take precautions to prevent exposure to the virus and minimize the risk of infection. For example, people who work with poultry and cows should use personal protective equipment and educate themselves about occupational risks when working with birds and mammals, as CDC and USDA have repeatedly recommended.

Ideally, following these four steps will help scientists and public health officials investigating HPAI H5N1 to answer the many remaining questions more quickly about how the virus is spreading, evolving, and affecting people, other mammals, and birds.

Photo of a wild bird. To the right is a colorized transmission electron micrograph of H5N1 virus particles (purple). H5N1 bird flu is widespread in wild birds worldwide, and in 2024 is causing a multistate outbreak in poultry and U.S. dairy cows. Bird photo by NIAID; micrograph, which has been repositioned and recolored by NIAID, is courtesy CDC. Picture Credits: NIAID and CDC
Photo of a wild bird. To the right is a colorized transmission electron micrograph of H5N1 virus particles (purple). H5N1 bird flu is widespread in wild birds worldwide, and in 2024 is causing a multistate outbreak in poultry and U.S. dairy cows. Bird photo by NIAID; micrograph, which has been repositioned and recolored by NIAID, is courtesy CDC. Picture Credits: NIAID and CDC

 

Bibliographic information:
M Ison and J Marrazzo, The Emerging Threat of H5N1 to Human Health, NEJM (2024), DOI: 10.1056/NEJMe2416323

 

Press release from the National Institute of Allergy and Infectious Diseases – NIH

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Protein interactions, between dystrophin and dystrobrevin, in Duchenne Muscular Dystrophy

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protein interactions Duchenne muscular dystrophy Parkinson scambio di informazioni intracellulare

New study uncovers key insights into protein interactions, between dystrophin and dystrobrevin, in Duchenne Muscular Dystrophy (DMD), paving way for more targeted therapies

Study results provide root explanations for how dystrophin functions on a molecular level, providing base-level insights into how muscular dystrophy therapies can be developed.

 

AURORA, Colo. (Dec. 31, 2024) – A groundbreaking study has shed light on the complex interactions between dystrophin, a protein critical to muscle stability, and its partner protein, dystrobrevin, offering new pathways for understanding and treating Duchenne Muscular Dystrophy (DMD).

Published in the December issue of the Journal of Biological Chemistry, researchers characterize the mysterious C-terminal (CT) domain of dystrophin and its role in stabilizing cellular membranes across various tissues.

DMD, a severe genetic disorder that causes muscle weakness and shortens lifespans, arises from mutations in the gene encoding dystrophin. While current treatments can extend patients’ lifespans, their high cost and limited efficacy underscore the urgent need for broader therapeutic approaches.

“This research highlights the intricate dynamics of dystrophin and dystrobrevin interactions, providing critical insights that could inform future treatment development,” said Krishna Mallela, professor of pharmaceutical sciences at the University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences and study lead author. “By understanding how these proteins function differently in various tissues, we’re one step closer to designing treatments that target the root causes of DMD.”

The study reveals that dystrophin’s CT domain interacts differently with the two major dystrobrevin isoforms, which bind to dystrophin. Variations in the amino acid composition of dystrobrevin proteins drive differences in binding affinity and interaction modes, influencing the stability of the dystrophin-associated protein complex across tissues, a key indication of DMD.

These findings offer a molecular explanation for the wide-ranging symptoms experienced by DMD patients, which extend beyond skeletal muscles to affect organs such as the heart and brain.

“This discovery is exceptional in advancing DMD care because, while there have been advancements in therapies, they have been approved in desperation. We need to get to the root of things to really hone in on effective treatments,” says Mallela. “Much like a car engine, how can you fix a car without understanding how the car engine functions?”

Bibliographic information:

Upadhyay, Vaibhav et al., Biophysical characterization of the dystrophin C-terminal domain: Dystrophin interacts differentially with dystrobrevin isoforms, Journal of Biological Chemistry, Volume 300, Issue 12, 108002, DOI: 10.1016/j.jbc.2024.108002 

About the University of Colorado Anschutz Medical Campus

The University of Colorado Anschutz Medical Campus is a world-class medical destination at the forefront of transformative science, medicine, education and patient care. The campus encompasses the University of Colorado health professional schools, more than 60 centers and institutes and two nationally ranked independent hospitals – UCHealth University of Colorado Hospital and Children’s Hospital Colorado – which see more than two million adult and pediatric patient visits yearly. Innovative, interconnected and highly collaborative, the CU Anschutz Medical Campus delivers life-changing treatments, patient care and professional training and conducts world-renowned research fueled by $910 million in annual research funding, including $757 million in sponsored awards and $153 million in philanthropic gifts.

Photo by Konstantin Kolosov

Press release from the University of Colorado Anschutz Medical Campus, by Kelsea Pieters

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Massive black hole in the early universe is lying dormant in its host galaxy, GN-1001830

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JWST buco nero dormiente GN-1001830

Massive black hole in the early universe spotted taking a ‘nap’ after overeating, and lying dormant in its host galaxy, GN-1001830

JWST buco nero dormiente GN-1001830 Illustrazione artistica che rappresenta l'aspetto potenziale del buco nero supermassiccio scoperto dal team di ricerca durante la sua fase di intensa attività super-Eddington. Crediti: Jiarong Gu
A study in Nature finds that black holes in the early Universe go through short periods of ultra-fast growth, followed by long periods of dormancy. Picture credits: Jiarong Gu

Scientists have spotted a massive black hole in the early universe that is ‘napping’ after stuffing itself with too much food.

Like a bear gorging itself on salmon before hibernating for the winter, or a much-needed nap after Christmas dinner, this black hole has overeaten to the point that it is lying dormant in its host galaxy, GN-1001830.

An international team of astronomers, led by the University of Cambridge, used the NASA/ESA/CSA James Webb Space Telescope to detect this black hole in the early universe, just 800 million years after the Big Bang.

The black hole is huge – 400 million times the mass of our Sun – making it one of the most massive black holes discovered by Webb at this point in the universe’s development. The black hole is so enormous that it makes up roughly 40% of the total mass of its host galaxy: in comparison, most black holes in the local universe are roughly 0.1% of their host galaxy mass.

However, despite its gigantic size, this black hole is eating, or accreting, the gas it needs to grow at a very low rate – about 100 times below its theoretical maximum limit – making it essentially dormant.

Such an over-massive black hole so early in the universe, but one that isn’t growing, challenges existing models of how black holes develop. However, the researchers say that the most likely scenario is that black holes go through short periods of ultra-fast growth, followed by long periods of dormancy. Their results are reported in the journal Nature.

When black holes are ‘napping’, they are far less luminous, making them more difficult to spot, even with highly-sensitive telescopes such as Webb. Black holes cannot be directly observed, but instead they are detected by the tell-tale glow of a swirling accretion disc, which forms near the black hole’s edges. The gas in the accretion disc becomes extremely hot and starts to glow and radiate energy in the ultraviolet range.

“Even though this black hole is dormant, its enormous size made it possible for us to detect,” said lead author Ignas Juodžbalis from Cambridge’s Kavli Institute for Cosmology. “Its dormant state allowed us to learn about the mass of the host galaxy as well. The early universe managed to produce some absolute monsters, even in relatively tiny galaxies.”

According to standard models, black holes form from the collapsed remnants of dead stars and accrete matter up to a predicted limit, known as the Eddington limit, where the pressure of radiation on matter overcomes the gravitational pull of the black hole. However, the sheer size of this black hole suggests that standard models may not adequately explain how these monsters form and grow.

“It’s possible that black holes are ‘born big’, which could explain why Webb has spotted huge black holes in the early universe,” said co-author Professor Roberto Maiolino, from the Kavli Institute and Cambridge’s Cavendish Laboratory. “But another possibility is they go through periods of hyperactivity, followed by long periods of dormancy.”

Working with colleagues from Italy, the Cambridge researchers conducted a range of computer simulations to model how this dormant black hole could have grown to such a massive size so early in the universe. They found that the most likely scenario is that black holes can exceed the Eddington limit for short periods, during which they grow very rapidly, followed by long periods of inactivity: the researchers say that black holes such as this one likely eat for five to ten million years, and sleep for about 100 million years.

“It sounds counterintuitive to explain a dormant black hole with periods of hyperactivity, but these short bursts allow it to grow quickly while spending most of its time napping,” said Maiolino.

Because the periods of dormancy are much longer than the periods of ultra-fast growth, it is in these periods that astronomers are most likely to detect black holes.

“This was the first result I had as part of my PhD, and it took me a little while to appreciate just how remarkable it was,” said Juodžbalis. “It wasn’t until I started speaking with my colleagues on the theoretical side of astronomy that I was able to see the true significance of this black hole.”

Due to their low luminosities, dormant black holes are more challenging for astronomers to detect, but the researchers say this black hole is almost certainly the tip of a much larger iceberg, if black holes in the early universe spend most of their time in a dormant state.

“It’s likely that the vast majority of black holes out there are in this dormant state – I’m surprised we found this one, but I’m excited to think that there are so many more we could find,” said Maiolino.

The observations were obtained as part of the JWST Advanced Deep Extragalactic Survey (JADES). The research was supported in part by the European Research Council and the Science and Technology Facilities Council (STFC), part of UK Research and Innovation (UKRI).

 

Bibliographic Information:

“A dormant, overmassive black hole in the early Universe”, by Ignas Juodžbalis, Roberto Maiolino, William M. Baker, Sandro Tacchella, Jan Scholtz, Francesco D’Eugenio, Raffaella Schneider, Alessandro Trinca, Rosa Valiante, Christa DeCoursey, Mirko Curti, Stefano Carniani, Jacopo Chevallard, Anna de Graaff, Santiago Arribas, Jake S. Bennett, Martin A. Bourne, Andrew J. Bunker, Stephane Charlot, Brian Jiang, Sophie Koudmani, Michele Perna, Brant Robertson, Debora Sijacki, Hannah Ubler, Christina C. Williams, Chris Willott, Joris Witstok, has been published on Nature (18-Dec-2024).

Press release from the University of Cambridge

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By observing NGC 346, Webb finds planet-forming discs lived longer in early Universe

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NGC 346 planet-forming discs The center of the image contains arcs of orange and pink that form a boat-like shape. One end of these arcs points to the top right of the image, while the other end point toward the bottom left. Another plume of orange and pink expands from the center to the top left of the image. To the right of this plume is a large cluster of white stars. There are various other white stars and a few galaxies of different sizes spread throughout the image. Ten, small, yellow circles overlaid at various points across the image indicate the positions of the ten stars surveyed in this study.

By observing NGC 346, Webb finds planet-forming discs lived longer in early Universe: new data refutes current theories of planet formation in Universe’s early days

 

The NASA/ESA/CSA James Webb Space Telescope just solved a conundrum by proving a controversial finding made with the NASA/ESA Hubble Space Telescope more than 20 years ago.

This image features NGC 346, one of the most dynamic star-forming regions in nearby galaxies, as seen by the NASA/ESA/CSA James Webb Space Telescope.
NCG 346 is located in the Small Magellanic Cloud (SMC), a dwarf galaxy close to our Milky Way.
Credit: NASA, ESA, CSA, STScI, A. Pagan (STScI)

In 2003, Hubble provided evidence of a massive planet around a very old star, almost as old as the Universe. Such stars possess only small amounts of heavier elements that are the building blocks of planets. This implied that some planet formation happened when our Universe was very young, and those planets had time to form and grow big inside their primordial discs, even bigger than Jupiter. But how? This was puzzling.

A side-by-side comparison of a Hubble image of the massive star cluster NGC 346 (left) versus a Webb image of the same cluster (right). The Hubble image shows the cluster in shades of blue against a black background punctuated by white stars of various sizes. Ethereal nebulosity, looking much like draped chiffon, dominates the image. The Webb view, in shades of pink and orange against a black background, is speckled with fewer stars than in the Hubble version. These stars are white and pink. Webb pierces through the cluster’s clouds to reveal more of its structure, which looks like twisted fibers.
This side-by-side comparison shows a Hubble image of the massive star cluster NGC 346 (left) versus a Webb image of the same cluster (right). While the Hubble image shows more nebulosity, the Webb image pierces through those clouds to reveal more of the cluster’s structure. NGC 346 has a relative lack of elements heavier than helium and hydrogen, making it a good proxy for stellar environments in the early, distant universe.
Credit: NASA, ESA, CSA, STScI, O. C. Jones (UK ATC), G. De Marchi (ESTEC), M. Meixner (USRA), A. Nota (ESA)

To answer this question, researchers used Webb to study stars in a nearby galaxy that, much like the early Universe, lacks large amounts of heavy elements. They found that not only do some stars there have planet-forming discs, but that those discs are longer-lived than those seen around young stars in our Milky Way galaxy.

“With Webb, we have a really strong confirmation of what we saw with Hubble, and we must rethink how we model planet formation and early evolution in the young Universe,” said study leader Guido De Marchi of ESA’s European Space Research and Technology Centre in Noordwijk, Netherlands.

A different environment in early times

In the early Universe, stars formed from mostly hydrogen and helium, and very few heavier elements such as carbon and iron, which came later through supernova explosions.

“Current models predict that with so few heavier elements, the discs around stars have a short lifetime, so short in fact that planets cannot grow big,” said the Webb study’s co-investigator Elena Sabbi, chief scientist for Gemini Observatory at the National Science Foundation’s NOIRLab in Tucson. “But Hubble did see those planets, so what if the models were not correct and discs could live longer?”

To test this idea, scientists trained Webb on the Small Magellanic Cloud, a dwarf galaxy that is one of the Milky Way’s nearest neighbors. In particular, they examined the massive, star-forming cluster NGC 346, which also has a relative lack of heavier elements. The cluster served as a nearby proxy for studying stellar environments with similar conditions in the early, distant Universe.

The center of the image contains arcs of orange and pink that form a boat-like shape. One end of these arcs points to the top right of the image, while the other end point toward the bottom left. Another plume of orange and pink expands from the center to the top left of the image. To the right of this plume is a large cluster of white stars. There are various other white stars and a few galaxies of different sizes spread throughout the image. Ten, small, yellow circles overlaid at various points across the image indicate the positions of the ten stars surveyed in this study.
This is a NASA/ESA/CSA James Webb Space Telescope image of NGC 346, a massive star cluster in the Small Magellanic Cloud, a dwarf galaxy that is one of the Milky Way’s nearest neighbors. With its relative lack of elements heavier than helium and hydrogen, the NGC 346 cluster serves as a nearby proxy for studying stellar environments with similar conditions in the early, distant Universe. Ten, small, yellow circles overlaid on the image indicate the positions of the ten stars surveyed in this study.
Credit: NASA, ESA, CSA, STScI, O. C. Jones (UK ATC), G. De Marchi (ESTEC), M. Meixner (USRA)

Hubble observations of NGC 346 from the mid 2000s revealed many stars about 20 to 30 million years old that seemed to still have planet-forming discs around them. This went against the conventional belief that such discs would dissipate after 2 or 3 million years.

“The Hubble findings were controversial, going against not only empirical evidence in our galaxy but also against the current models,” said De Marchi. “This was intriguing, but without a way to obtain spectra of those stars, we could not really establish whether we were witnessing genuine accretion and the presence of discs, or just some artificial effects.”

Now, thanks to Webb’s sensitivity and resolution, scientists have the first-ever spectra of forming, Sun-like stars and their immediate environments in a nearby galaxy.

“We see that these stars are indeed surrounded by discs and are still in the process of gobbling material, even at the relatively old age of 20 or 30 million years,” said De Marchi. “This also implies that planets have more time to form and grow around these stars than in nearby star-forming regions in our own galaxy.”

By observing NGC 346, Webb finds planet-forming discs lived longer in early Universe: new data refutes current theories of planet formation in Universe’s early days. This image features NGC 346, one of the most dynamic star-forming regions in nearby galaxies, as seen by the NASA/ESA/CSA James Webb Space Telescope.
NCG 346 is located in the Small Magellanic Cloud (SMC), a dwarf galaxy close to our Milky Way.
Credit: NASA, ESA, CSA, STScI, A Pagan (STScI)

A New Way of Thinking

This finding refutes previous theoretical predictions that when there are very few heavier elements in the gas around the disc, the star would very quickly blow away the disc. So the disc’s life would be very short, even less than a million years. But if a disc doesn’t stay around the star long enough for the dust grains to stick together and pebbles to form and become the core of a planet, how can planets form?

The researchers explained that there could be two distinct mechanisms, or even a combination, for planet-forming discs to persist in environments scarce in heavier elements.

First, to be able to blow away the disc, the star applies radiation pressure. For this pressure to be effective, elements heavier than hydrogen and helium would have to reside in the gas. But the massive star cluster NGC 346 only has about ten percent of the heavier elements that are present in the chemical composition of our Sun. Perhaps it simply takes longer for a star in this cluster to disperse its disc.

The second possibility is that, for a Sun-like star to form when there are few heavier elements, it would have to start from a larger cloud of gas. A bigger gas cloud will produce a bigger disc. So there is more mass in the disc and therefore it would take longer to blow the disc away, even if the radiation pressure were working in the same way.

“With more matter around the stars, the accretion lasts for a longer time,” said Sabbi. “The discs take ten times longer to disappear. This has implications for how you form a planet, and the type of system architecture that you can have in these different environments. This is so exciting.”

The science team’s paper appears in the 16 December 2024 issue of The Astrophysical Journal.

planet-forming discs Graphic titled Star in NGC 346, Molecular Hydrogen in Protoplanetary Disk, NIRSpec Microshutter Array Spectroscopy showing brightness of 2.02- to 2.37-micron light of a star and its environment (plotted in yellow) and a star’s environment only (plotted in pink) on an xy graph of brightness versus wavelength in microns. Two wavelength bands, ranging from 2.05 to 2.07 and 2.16 to 2.18, are highlighted in red and labeled Hot Atomic Helium, He. A band from 2.11 to 2.13 in blue is labeled Cold Molecular Hydrogen, H 2. The spectrum of the star plus environment (yellow) has prominent peaks at 2.06 and 2.17 microns (He), and at 2.12 microns (H). The spectrum of the star’s environment only (pink) also has peaks at 2.06 and 2.17 microns (He), but not at 2.12 (H). The two spectra are offset vertically for readability. An inset shows them plotted with the same vertical alignment: the helium peaks on the star plus environment spectrum are slightly taller than those of the environment only.
This graph shows, on the bottom left in yellow, a spectrum of one of the 10 target stars in this study (as well as accompanying light from the immediate background environment). Spectral fingerprints of hot atomic helium, cold molecular hydrogen, and hot atomic hydrogen are highlighted. On the top left in magenta is a spectrum slightly offset from the star that includes only light from the background environment. This second spectrum lacks a spectral line of cold molecular hydrogen.
On the right is the comparison of the top and bottom lines. This comparison shows a large peak in the cold molecular hydrogen coming from the star but not its nebular environment. Also, atomic hydrogen shows a larger peak from the star. This indicates the presence of a protoplanetary disc immediately surrounding the star. The data was taken with the microshutter array on the James Webb Space Telescope’s NIRSpec (Near-Infrared Spectrometer) instrument.
Credit: NASA, ESA, CSA, J. Olmsted (STScI)

Press release from ESA Webb

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