Chandra X-Ray Observatory Captures Breathtaking New Images

 

The images feature data from the Smithsonian Astrophysical Observatory along with a host of other NASA telescopes including the James Webb Space Telescope, Hubble Space Telescope and more.

Top row:

N79 is a giant region of star formation in the Large Magellanic Cloud, a small satellite neighbor galaxy to the Milky Way. Chandra sees the hot gas created by young stars, which helps astronomers better understand how stars like our Sun formed billions of years ago. [X-rays from Chandra (purple) and infrared data from Webb (blue, grey and gold)]

NGC 2146 is a spiral galaxy with one of its dusty arms obscuring the view of its center from Earth.. X-rays from Chandra reveal double star systems and hot gas being expelled from the galaxy by supernova explosions and strong winds from giant stars. [X-rays from Chandra (pink and purple), optical data from Hubble and the Las Cumbres Observatory in Chile and infrared data from NSF’s Kitt Peak (red, green and blue)]

IC 348 is a star-forming region in our Milky Way galaxy. The wispy structures that dominate the image are interstellar material that reflects light from the cluster’s stars. The point-like sources in Chandra’s X-ray data are young stars forming in the cluster. [X-rays from Chandra (red, green and blue) and Webb infrared data (pink, orange and purple)]

Middle row:

M83, a spiral galaxy similar to the Milky Way, is oriented face-on toward Earth, providing an unobstructed view of its entire structure that is often not possible with galaxies viewed atdifferent angles. Chandra has detected the explosions of stars, or supernovas, and their aftermath across M83. [X-rays from Chandra (red, green and blue) with ground-based optical data (pink, gold and gray)].

M82 is a so-called starburst galaxy where stars are forming at rates tens to hundreds of times higher than normal galaxies. Chandra sees supernovas that produce expanding bubbles of multimillion-degree gas that extend for millions of light-years away from the galaxy's disk. [X-rays from Chandra (purple) with Hubble optical data (red, green, and blue)]

NGC 1068 is a relatively nearby spiral galaxy containing a black hole at its center that is twice as massive as the one in the Milky Ways. Chandra shows a million-mile-per-hour wind is being driven from NGC 1068’s black hole which lights (?) up the center of the galaxy in X-rays. [X-rays from Chandra (blue), radio data from NSF’s VLA radio data (pink), and optical data from Hubble and Webb (yellow, grey and gold)]

Bottom row:

NGC 346 is a young cluster home to thousands of newborn stars. The cluster’s most massive stars createpowerful winds and produce intense radiation. X-rays from Chandra reveal output from massive stars in the cluster and diffuse emission from a supernova remnant, the glowing debris of an exploded star. [X-rays from Chandra (purple) with optical and ultraviolet from Hubble blue, brown and gold)]

IC 1623 is a system where two galaxies are erging. As the galaxies collide, they trigger new bursts of star formation that glow intensely in certain kinds of light which is detected by Chandara and other telescopesThe merging galaxies may also be in the process of forming a supermassive black hole. [X-rays from Chandra (magenta) with Webb infrared data (red, gold and gray)]

Westerlund 1 is the biggest and closest “super” star cluster to Earth. Data from Chandra and other telescopes is helping astronomers delve deeper into this galactic factory where stars are being produced at extraordinarily high rates. Observations from Chandra have uncovered thousands of individual stars pumping out X-ray emission into the cluster. [X-rays from Chandra (pink, blue, purple and orange) with Webb infrared data (yellow, gold and blue) and Hubble optical data (cyan, grey and light yellow)]

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center, part of the Center for Astrophysics | Harvard & Smithsonian, controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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Media Contact:

Megan Watzke
Chandra X-Ray Observatory
mwatzke@cfa.harvard.edu

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Image Credits:

NGC 2146: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI and NOIRLab/NSF/AURA; Infrared: NSF/NOAO/KPNO; Image Processing: NASA/CXC/SAO/L. Frattare

IC 348: X-ray: NASA/CXC/SAO; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/J. Major

M83: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/AURA/STScI, Hubble Heritage Team, W. Blair (STScI/Johns Hopkins University) and R. O'Connell (University of Virginia); Image Processing: NASA/CXC/SAO/L. Frattare

M82: X-ray: NASA/CXC/SAO; Optical/IR: NASA/ESA/STScI; Image Processing: NASA/CXC/SAO/J. Major

NGC 1068: X-ray: NASA/CXC/SAO; Optical/IR: NASA/ESA/CSA/STScI (HST and JWST); Radio: NSF/NRAO/VLA; Image Processing: NASA/CXC/SAO/J. Schmidt and N. Wolk

NGC 346: X-ray: NASA/CXC/SAO; Optical/IR: NASA/ESA/CSA/STScI (HST and JWST); Radio: NSF/NRAO/VLA; Image Processing: NASA/CXC/SAO/J. Schmidt and N. Wolk

IC 1623: X-ray: NASA/CXC/SAO; IR: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare and J. Major

Westerlund 1: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; IR: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare

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Astronomers Discover Rare Distant Object in Sync with Neptune

A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond Neptune, from a class known as trans-Neptunian objects, that is moving in rhythm with the giant planet. This image shows the orbits of all of the objects discovered in the Outer Solar System Origins Survey. The orbit of 2020 VN40 is the thickest one, tilted up and to the left from the orbits of most of the objects. The orbits of the giant planets Jupiter, Saturn, Uranus, and Neptune are the white circles. Credit: Rosemary Pike, CfA

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This object, called 2020 VN40, is the first confirmed body that orbits the sun once for every ten orbits Neptune completes.

Cambridge, MA — A team of astronomers led by the Center for Astrophysics | Harvard & Smithsonian has discovered a rare object far beyond Neptune, from a class known as trans-Neptunian objects, that is moving in rhythm with the giant planet. This object, called 2020 VN40, is the first confirmed body that orbits the sun once for every ten orbits Neptune completes.

This discovery helps scientists understand how objects in the outer solar system behave and how they got there. It supports the idea that many distant objects are temporarily "caught" in Neptune’s gravity as they drift through space.

"This is a big step in understanding the outer solar system," said Rosemary Pike, lead researcher from the Center for Astrophysics | Harvard & Smithsonian. "It shows that even very distant regions influenced by Neptune can contain objects, and it gives us new clues about how the solar system evolved."

The finding was published this month in The Planetary Science Journal, a publication of the American Astronomical Society.

The discovery was made by the Large inclination Distant Objects (LiDO) survey, which searched for unusual objects in the outer solar system. This survey used the Canada-France-Hawaii Telescope for the main survey operations, and Gemini Observatory and Magellan Baade for additional observations.

The survey was designed to search for bodies with orbits that extend far above and below the plane of the Earth's orbit around the sun, part of the outer solar system that hasn’t been well-studied.

"It has been fascinating to learn how many small bodies in the solar system exist on these very large, very tilted orbits," said Dr. Samantha Lawler (University of Regina), a core member of the LiDO team. The object’s average distance is about 140 times farther from the sun than Earth and follows a very tilted path around the solar system.

What makes 2020 VN40 even more interesting is how it moves compared to Neptune. Most objects with a simple ratio of the duration of their orbit compared to the duration of Neptune's orbit always come closest to the sun when Neptune is far away. In contrast, 2020 VN40 comes closest to the sun when Neptune is very close by, if you look at their positions from above the solar system. The tilt of 2020 VN40's orbit means that the objects are not actually close, because 2020 VN40 is actually far below the solar system- they only appear close when flattened onto a map. All other known resonant trans-Neptunian objects orbit such that they avoid this alignment at their closest approach to the sun, even in the flattened view.

"This new motion is like finding a hidden rhythm in a song we thought we knew," said Ruth Murray-Clay (University of California Santa Cruz), co-author of the study. "It could change how we think about the way distant objects move."

These findings suggest that highly tilted orbits can lead to new and unexpected types of motion. The LiDO survey has already found over 140 distant objects, and more discoveries are expected from future surveys. With telescopes like the Vera C. Rubin Observatory, scientists hope to find many more objects like 2020 VN40.

"This is just the beginning," said Kathryn Volk of the Planetary Science Institute. "We’re opening a new window into the solar system’s past."

Source: Harvard-Smithsonian Center for Astrophysics (CfA)

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Resources

The Gemini North telescope is one half of the International Gemini Observatory, which is funded in part by the U.S. National Science Foundation and operated by NSF NOIRLab.

DOI: 10.3847/PSJ/addd22

https://iopscience.iop.org/article/10.3847/PSJ/addd22

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Media Contact:

Christine Buckley
Director of Communications
Center for Astrophysics | Harvard & Smithsonian
christine.buckley@cfa.harvard.edu

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A New GPS for the Intergalactic Medium: Astronomers Have Found the Home Address for Universe's "Missing" Matter

A landmark study led by the Center for Astrophysics | Harvard & Smithsonian (CfA) has pinpointed the Universe’s “missing” matter using Fast Radio Bursts (FRBs)— brief, bright radio signals from distant galaxies— as a guide. This artist’s conception depicts a bright pulse of radio waves (the FRB) on its journey through the fog between galaxies, known as the intergalactic medium. Long wavelengths, shown in red, are slowed down compared to shorter, bluer wavelengths, allowing astronomers to “weigh” the otherwise invisible ordinary matter. Credit: Melissa Weiss/CfA

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Cambridge, MA— A new landmark study has pinpointed the location of the Universe's "missing" matter, and detected the most distant fast radio burst (FRB) on record. Using FRBs as a guide, astronomers at the Center for Astrophysics | Harvard & Smithsonian (CfA) and Caltech have shown that more than three-quarters of the Universe's ordinary matter has been hiding in the thin gas between galaxies, marking a major step forward in understanding how matter interacts and behaves in the Universe. They’ve used the new data to make the first detailed measurement of ordinary matter distribution across the cosmic web.

For decades, scientists have known that at least half of the Universe's ordinary, or baryonic matter—composed primarily of protons—was unaccounted for. Previously, astronomers have used techniques including X-ray emission and ultraviolet observations of distant quasars to find hints of vast amounts of this missing mass in the form of very thin, warm gas in between galaxies. Because that matter exists as hot, low-density gas, it was largely invisible to most telescopes, leaving scientists to estimate but not confirm its amount or location.

Enter FRBs— brief, br ight radio signals from distant galaxies that scientists only recently showed could measure baryonic matter in the Universe, but until now could not find its location. In the new study, researchers analyzed 60 FRBs, ranging from ~11.74 million light years away—FRB20200120E in galaxy M81—to ~9.1 billion light years away—FRB 20230521B, the most distant FRB on record. This allowed them to pin down the missing matter to the space between galaxies, or the intergalactic medium (IGM).

"The decades-old 'missing baryon problem' was never about whether the matter existed," said Liam Connor, CfA astronomer and lead author of the new study. "It was always: Where is it? Now, thanks to FRBs, we know: three-quarters of it is floating between galaxies in the cosmic web." In other words, scientists now know the home address of the “missing” matter.

By measuring how much each FRB signal was slowed down as it passed through space, Connor and his team tracked the gas along its journey. "FRBs act as cosmic flashlights," Connor, who is also an assistant professor of astronomy at Harvard, said. "They shine through the fog of the intergalactic medium, and by precisely measuring how the light slows down, we can weigh that fog, even when it's too faint to see."

The results were clear: Approximately 76% of the Universe's baryonic matter lies in the IGM. About 15% resides in galaxy halos, and a small fraction is burrowed in stars or amid cold galactic gas.

This distribution lines up with predictions from advanced cosmological simulations, but has never been directly confirmed until now.

"It's a triumph of modern astronomy," said Vikram Ravi, an assistant professor of astronomy at Caltech and co-author of the paper. "We're beginning to see the Universe's structure and composition in a whole new light, thanks to FRBs. These brief flashes allow us to trace the otherwise invisible matter that fills the vast spaces between galaxies."

Finding the missing baryons isn’t just an exercise in building an address book or taking a census. Their distribution holds the key to unlocking deep mysteries about how galaxies form, how matter clumps in the Universe, and how light travels across billions of light-years.

"Baryons are pulled into galaxies by gravity, but supermassive black holes and exploding stars can blow them back out—like a cosmic thermostat cooling things down if the temperature gets too high," said Connor. "Our results show this feedback must be efficient, blasting gas out of galaxies and into the IGM."

And this is just the beginning for FRB cosmology. "We're entering a golden age," said Ravi, who also serves as the co-PI of Caltech’s Deep Synoptic Array-110 (DSA-110). "Next-generation radio telescopes like the DSA-2000 and the Canadian Hydrogen Observatory and Radio-transient Detector will detect thousands of FRBs, allowing us to map the cosmic web in incredible detail."/div>
The study is published today in Nature Astronomy.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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Reference

Connor, L., et al. (2025). A gas-rich cosmic web revealed by the partitioning of the missing baryons. Nature Astronomy. doi:10.1038/s41550-025-02566-y

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Record-Breaking Cosmic Structure Discovered in Colossal Galaxy Cluster

This new composite image made with X-rays from NASA’s Chandra X-ray Observatory (blue and purple), radio data from the MeerKAT radio telescope (orange and yellow), and an optical image from PanSTARRS (red, green, and blue) shows PLCK G287.0+32.9. This massive galaxy cluster, located about 5 billion light-years from Earth, was first detected by astronomers in 2011. Credit: X-ray: NASA/CXC/CfA/K. Rajpurohit et al.; Optical: PanSTARRS; Radio: SARAO/MeerKAT; Image processing: NASA/CXC/SAO/N. Wolk. High Resolution Image

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A CfA astronomer and her team have imaged the largest known cloud of energetic particles surrounding a galaxy cluster, and raised new questions about what powers and re-energizes particles in the Universe over time.

Cambridge, MA - Astronomers have discovered the largest known cloud of energetic particles surrounding a galaxy cluster— spanning nearly 20 million light-years. The finding challenges long-standing theories about how particles stay energized over time. Instead of being powered by nearby galaxies, this vast region seems to be energized by giant shockwaves and turbulence moving through the hot gas between galaxies.

The results of the new study, led by scientists at the Center for Astrophysics | Harvard & Smithsonian (CfA), were presented today in a press conference at the 246th meeting of the American Astronomical Society (AAS).

Located five billion light-years from Earth, PLCK G287.0+32.9 is a massive galaxy cluster that has piqued the interest of astronomers since it was first detected in 2011. Earlier studies spotted two bright relics— giant shockwaves that lit up the cluster's edges. But they missed the vast, faint radio emission that fills the space between them. New radio images reveal that the entire cluster is wrapped in a faint radio glow, nearly 20 times the diameter of the Milky Way, suggesting that something much larger and more powerful is at work.

"We expected a bright pair of relics at the cluster's edges, which would have matched prior observations, but instead we found the whole cluster glowing in radio light," said lead author, Dr. Kamlesh Rajpurohit, a Smithsonian astronomer at the CfA. "A cloud of energetic particles this large has never been observed in this galaxy cluster or any other." The prior record holder, Abell 2255, spans roughly 16.3 million light-years.

Deep in the cluster's central region, the team detected a radio halo approximately 11.4 million light-years across, the first of its size seen at 2.4 GHz, a radio frequency where halos this large are usually not visible. The findings raise questions for the team because they provide strong evidence for the presence of cosmic ray electrons and magnetic fields stretched out to the periphery of clusters. However, it remains unclear how these electrons accelerated over such large distances.

"Very extended radio halos are mostly only visible at lower frequencies because the electrons that produce them have lost energy — they're old and have cooled over time," said Rajpurohit. "With the discovery of this enormous size halo we are now seeing radio emission extending all the way between the giant shocks and beyond, filling the entire cluster. That suggests something is actively accelerating, or re-accelerating the electrons, but none of the usual suspects apply. We think that giant shockwaves or turbulence could be responsible, but we need more theoretical models to find a definitive answer." The discovery provides researchers a new way to study cosmic magnetic fields— one of the major unanswered questions in astrophysics— that could help scientists understand how magnetic fields shape the Universe on the largest scales.

"We're starting to see the Universe in ways we never could before," said Rajpurohit. "And that means rethinking how energy and matter move through its largest structures." Observations with NASA's Chandra X-ray Observatory, operated by the Smithsonian Astrophysical Observatory, reveal a box-shaped structure, a comet-like tail, and several other distinct features in the cluster's hot gas, suggesting that the cluster is highly disturbed. Some of these X-ray features coincide with radio-detected structures, suggesting giant shocks and turbulence driven by mergers accelerating or re-accelerating electrons. In the center of the cluster, some of these features may be caused by a merger of two smaller galaxy clusters, or from outbursts produced by a supermassive black hole, or both.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News Release

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Media Contact:

Amy C. Oliver
Public Affairs Officer
Center for Astrophysics | Harvard & Smithsonian
amy.oliver@cfa.harvard.edu

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Resources

K. Rajpurohit et al."Diffuse Radio Emission Spanning 6 Mpc in the Highly Disturbed Galaxy Cluster PLCK G287.0+32.9," pending submission

K. Rajpurohit et al. "Radial Profiles of Radio Halos in Massive Galaxy Clusters: Diffuse Giants Over 2 Mpc" submitted to ApJ, preprint is here

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Key Building Block for Life Discovered in Planet-Forming Disk

This artist's conception shows a disk of dust and gas surrounding a young star with a large cavity carved out by a forming giant planet. The warm methanol gas tracing the dust cavity wall is highlighted. These molecules originate from ices rich in organic matter that are heated by radiation from the star, forming gas. The detection of methanol, as well as the methanol isotopes, supports the idea that interstellar ices can survive the formation of planet-forming disks. Credit: CfA/M. Weiss. High Resolution Image

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CfA astronomers have helped discover rare types of methanol, a building block required for life as we know it to form.

Cambridge, MA - Astronomers have found a rare form of methanol, a type of alcohol, in a planet-forming disk, providing a critical step in understanding how life beyond Earth may form. This result reveals vital details about the chemical composition of the ice in disks that form planets, and what organic molecules are available for comets to deliver to planets, including in our Solar System.

While astronomers have found evidence for other more complex molecules in planet-forming disks around other stars, this latest discovery is the first time that rare isotopes of methanol have been detected. Isotopes are different versions of a chemical element or compound that have the same numbers of protons but different numbers of neutrons.

"Finding these isotopes of methanol gives essential insight into the history of ingredients necessary to build life here on Earth," said Alice Booth of the Center for Astrophysics | Harvard & Smithsonian (CfA) who led the study.

Booth and colleagues discovered these isotopes of methanol around HD 100453, a star with about 1.6 times the mass of the Sun located about 330 light-years from Earth. They used data from the Atacama Large Millimeter-submillimeter Array (ALMA), an international radio array in the Atacama Desert in Chile supported by the National Science Foundation in the US.

Scientists, like this research team and many others, look at planet-forming disks around stars as laboratories because they reveal the amounts of complex organic molecules that are present when planets and comets are assembling.

"Finding out methanol is definitely part of this stellar cocktail is really a cause for celebration," said co-author Lisa Wölfer of the Massachusetts Institute of Technology. "I’d say that the vintage of more than a million years, which is the age of HD 100453, is quite a good one."

What made this discovery possible? Because HD 100453 has a higher mass than the Sun, it has a warmer, planet-forming disk around it. This causes molecules in the disk, including methanol, to exist as gas at larger distances from the star, enabling ALMA to detect it. By contrast, less massive stars like the Sun have cooler disks so methanol would be locked up in ice and ALMA cannot detect it.

The ratio of methanol to other simple organic molecules seen in HD 100453 is about the same as it is in comets in our Solar System. This reinforces the potential to learn about our own planet’s history by studying these more distant early worlds.

More specifically, this work suggests that the ices within planet-forming disks, which serve as the material that will eventually clump together to form comets, are rich in complex organic molecules.

"This research supports the idea that comets may have played a big role in delivering important organic material to the Earth billions of years ago," said co-author Milou Temmink of Leiden Observatory in the Netherlands. "They may be the reason why life, including us, was able to form here."

Methanol had previously been detected in several star-forming disks, but detecting isotopes of methanol -- which are 10 to 100 times less abundant -- is an important step because it confirms that the disks are likely rich in organic molecules not yet detected in HD 100453, including simple amino acids and sugars such as glycine and glycolaldehyde.

High levels of methanol in the disk likely come from the inner edge of a ring of dust about 1.5 billion miles from the star, equivalent to 16 times the distance between the Sun and the Earth.

The paper describing these results is available online and appears in The Astrophysical Journal.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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Media Contact:

Peter Edmonds
Interim CfA Public Affairs Officer
Center for Astrophysics | Harvard & Smithsonian
617-571-7279
pedmonds@cfa.harvard.edu

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Astronomers Find Far-flung “Super Earths” Are Not Farfetched

This artist's concept illustrates the results of a new study that measured the masses of many planets relative to the stars that host them, leading to new information about populations of planets in the direction of the bulge of the Milky Way. This study, published in the journal Science, shows that super-Earths are common and places them in context with gas giant planets. Credit: Westlake University

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A new study shows that planets bigger than Earth and smaller than Neptune are common outside the Solar System

The same international team including astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA) has also announced the discovery of a planet about twice the size of Earth orbiting its star farther out than Saturn is to the Sun.

These results are another example of how planetary systems can be different from our Solar System.

"We found a 'super Earth' -- meaning it's bigger than our home planet but smaller than Neptune -- in a place where only planets thousands or hundreds of times more massive than Earth were found before" said Weicheng Zang, a CfA Fellow. He is the lead author of a paper describing these results in the latest issue of the journal Science.

The discovery of this new, farther-out super Earth is even more significant because it is part of a larger study. By measuring the masses of many planets relative to the stars that host them, the team has discovered new information about the populations of planets across the Milky Way.

This study used microlensing, an effect where light from distant objects is amplified by an intervening body such as a planet. Microlensing is particularly effective at finding planets at large distances – approximately between the orbits of Earth and Saturn – from their host stars. The largest study of its kind, this work has about three times more planets and includes planets that are about eight times smaller than previous samples of planets found using the microlensing technique.

The researchers used data from the Korea Microlensing Telescope Network (KMTNet). This network consists of three telescopes in Chile, South Africa, and Australia, which allows for uninterrupted monitoring of the night sky.

"The current data provided a hint of how cold planets form," said Professor Shude Mao of Tsinghua University and Westlake University, China. "In the next few years, the sample will be a factor of four larger, and thus we can constrain how these planets form and evolve even more stringently with KMTNet data."

Our Solar System consists of four small, rocky, inner planets (Mercury, Venus, Earth and Mars) and four large, gaseous, outer planets (Jupiter, Saturn, Uranus and Neptune). The searches for exoplanets to date using other techniques, i.e., transiting planet from telescopes like Kepler and TESS and radial velocity searches, have shown that other systems can contain a variety of small, medium, and large planets in orbits inside that of the Earth.

The latest work from the CfA-led team shows that such super-Earth planets are also common in the outer regions of other solar systems. "This measurement of the planet population from planets somewhat larger than Earth all the way to the size of Jupiter and beyond shows us that planets, and especially super-Earths, in orbits outside the Earth's orbit are abundant in the Galaxy" said co-author Jennifer Yee of the Smithsonian Astrophysical Observatory, which is part of the CfA.

"This result suggests that in Jupiter-like orbits, most planetary systems may not mirror our Solar System," said co-author Youn Kil Jung of the Korea Astronomy and Space Science Institute that operates the KMTNet.

The researchers are also looking to determine how many super Earths exist versus the number of Neptune-sized planets. This study shows that there are at least as many super Earths as Neptune-size planets.

Other CfA contributors to this study include post-doctoral fellow In-Gu Shin, former Harvard undergraduate student Hangyue Wang (now at Stanford), and Sun-Ju Chung, a KASI scientist who visited CfA on sabbatical from 2022-2023.

In addition to KMTNet, the Optical Gravitational Lens Experiment (OGLE) and Microlensing Observations in Astrophysics (MOA) survey groups contributed data for the planet characterization.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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CfA Scientists Play Important Role in New NASA Mission

This artist's impression of SPHEREx shows the spacecraft as it will appear when in low-Earth orbit. During its 27-month nominal mission, SPHEREx will conduct four all-sky surveys to study the early history of the cosmos and search for interstellar molecules such as water and other compounds thought to be precursors of life as we know it.  Credit: NASA/JPLM High Resolution Image

A new NASA mission with major roles from scientists at the Center for Astrophysics | Harvard & Smithsonian (CfA) will help answer questions about why the large scale structure of the Universe looks the way it does today, how galaxies form and evolve, and what are the abundances of water and other key ingredients for life in our Galaxy.

SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) will identify specific atoms and molecules in millions of objects across space using their unique signatures in optical and infrared spectra, which show how their light depends on wavelength.

After its launch into space on March 11, 2025 from the Vandenberg Space Force Base in California, SPHEREx will survey the entire sky four times over its 25-month mission. Astronomers will be able to combine SPHEREx’s ability to scan large sections of the sky quickly with more targeted studies Harvard-Smithsonian Center for Astrophysics (CfA) from ground-based telescopes and others in space like NASA’s James Webb Space Telescope (JWST).

The CfA will lead the investigation into the abundances and distributions of molecules that are vital for life. Specifically, SPHEREx will conduct a survey along almost 10 million lines of sight in the Milky Way and the Magellanic Clouds, neighboring galaxies to our own. This survey will reveal crucial life-enabling molecules like water (H₂O), carbon monoxide (CO), and carbon dioxide (CO₂) in their icy states on the surfaces of interstellar dust grains.

These data will enable CfA scientists to evaluate the ice content in each direction and will help to trace the evolution of these ices as they transition from molecular clouds to planet-forming disks and, ultimately, to newly forming planets.  JWST can follow up the most interesting targets identified by SPHEREx, making the two facilities a particularly powerful combination for studying how Solar System planets as well as planets around other stars get their key ingredients for life.

The CfA SPHEREx team is led by Dr.Gary Melnick and includes Drs. Matthew Ashby, Joseph Hora, and Volker Tolls, who are joined by visiting scientist, Dr. Jaeyeong Kim, from the Korean Astronomy and Space Science Institute.

SPHEREx’ data will be freely available to scientists around the world, providing new information about hundreds of millions of cosmic objects. More about SPHEREx at the CfA can be found at https://www.cfa.harvard.edu/facilities-technology/telescopes-instruments/spherex

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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Runaway Stars Reveal Hidden Black Hole In Milky Way’s Nearest Neighbor

Artist’s impression of a hypervelocity star ejected from the Large Magellanic Cloud (shown on right). When a binary star system ventures too close to a supermassive black hole, the intense gravitational forces tear the pair apart. One star is captured into a tight orbit around the black hole, while the other is flung outward at extreme velocities—often exceeding millions of miles per hour—becoming a hypervelocity star. The inset illustration depicts this process: the original binary’s orbital path is shown as interwoven lines, with one star being captured by the black hole (near center of inset) while the other is ejected into space (lower right). Credit: CfA/Melissa Weiss.  High Resolution Image

Labeled artist’s impression of a hypervelocity star ejected from the Large Magellanic Cloud (shown on right). When a binary star system ventures too close to a supermassive black hole, the intense gravitational forces tear the pair apart. One star is captured into a tight orbit around the black hole, while the other is flung outward at extreme velocities—often exceeding millions of miles per hour—becoming a hypervelocity star. The inset illustration depicts this process: the original binary’s orbital path is shown as interwoven lines, with one star being captured by the black hole (near center of inset) while the other is ejected into space (lower right). Credit: CfA/Melissa Weiss.  High Resolution Image

Artist’s impression of a hypervelocity star ejected from the Large Magellanic Cloud. When a binary star system ventures too close to a supermassive black hole, the intense gravitational forces tear the pair apart. One star is captured into a tight orbit around the black hole, while the other is flung outward at extreme velocities—often exceeding millions of miles per hour—becoming a hypervelocity star. This illustration depicts this process: the original binary’s orbital path is shown as interwoven lines, with one star being captured by the black hole (near center) while the other is ejected into space (lower right). Credit: CfA/Melissa Weiss.  High Resolution Image

This is an image of the Large Magellanic Cloud (LMC), one of the nearest galaxies to our Milky Way, as viewed by ESA’s Gaia satellite using information from the mission’s second data release. This view has been compiled by mapping the total amount of radiation detected by Gaia in each pixel, combined with measurements of the radiation taken through different filters on the spacecraft to generate color information. Astronomers have announced the discovery strong evidence for a supermassive black hole in the LMC, which would be the closest to Earth outside of the Milky Way galaxy. Credit: ESA/Gaia/DPAC. High Resolution Image

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CfA astronomers have found strong evidence for a supermassive black hole in the Large Magellanic Cloud, a satellite galaxy to the Milky Way

Cambridge, MA - Astronomers have discovered strong evidence for the closest supermassive black hole outside of the Milky Way galaxy. This giant black hole is located in the Large Magellanic Cloud, one of the nearest galactic neighbors to our own.

To make this discovery, researchers traced the paths with ultra-fine precision of 21 stars on the outskirts of the Milky Way. These stars are traveling so fast that they will escape the gravitational clutches of the Milky Way or any nearby galaxy. Astronomers refer to these as "hypervelocity" stars.

Similar to how forensic experts recreate the origin of a bullet based on its trajectory, researchers determined where these hypervelocity stars come from. They found that about half are linked to the supermassive black hole at the center of the Milky Way. However, the other half originated from somewhere else: a previously-unknown giant black hole in the Large Magellanic Cloud (LMC).

"It is astounding to realize that we have another supermassive black hole just down the block, cosmically speaking," said Jesse Han of the Center for Astrophysics | Harvard & Smithsonian (CfA), who led the new study. "Black holes are so stealthy that this one has been practically under our noses this whole time."

The researchers found this secretive black hole by using data from the European Space Agency’s Gaia mission, a satellite that has tracked more than a billion stars throughout the Milky Way with unprecedented accuracy. They also used an improved understanding of the LMC’s orbit around the Milky Way recently obtained by other researchers.

"We knew that these hypervelocity stars had existed for a while, but Gaia has given us the data we need to figure out where they actually come from," said co-author Kareem El-Badry of Caltech in Pasadena, California. "By combining these data with our new theoretical models for how these stars travel, we made this remarkable discovery."

Hypervelocity stars are created when a double-star system ventures too close to a supermassive black hole. The intense gravitational pull from the black hole rips the two stars apart, capturing one star into a close orbit around it. Meanwhile, the other orphaned star is jettisoned away at speeds exceeding several million miles per hour -- and a hypervelocity star is born.

A significant piece of the team’s research was a prediction by their theoretical model that a supermassive black hole in the LMC would create a cluster of hypervelocity stars in one corner of the Milky Way because of how the LMC moves around the Milky Way. The stars ejected along the direction of the LMC’s motion should receive an extra boost in speed. Indeed, their data revealed the existence of such a cluster.

The team found that the properties of the hypervelocity stars cannot be explained by other mechanisms, such as stars being ejected when their companions undergo a supernova explosion, or stars being ejected by a mechanism like that described above for a double star system, but without a supermassive black hole being involved.

"The only explanation we can come up with for this data is the existence of a monster black hole in our galaxy next door," said co-author Scott Lucchini, also of CfA. "So in our cosmic neighborhood it’s not just the Milky Way’s supermassive black hole evicting stars from its galaxy."

Using the speeds of the stars and the relative number of ones ejected by the LMC and Milky Way supermassive black holes, the team determined that the mass of the LMC black hole is about 600,000 times the mass of the Sun. For comparison, the supermassive black hole in the Milky Way has about 4 million solar masses. Elsewhere in the Universe, there are supermassive black holes with billions of times more mass than the Sun.

A paper describing these results has been accepted for publication in The Astrophysical Journal and is available here.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Astronomers Detect Missing Ingredient in Cooking Up Stars

This image of Arp 220 was taken by NASA’s Hubble Space Telescope. Arp 220 is the aftermath of a collision between two spiral galaxies. It is the brightest of the three galactic mergers closest to Earth, about 250 million light-years away. Astronomers studied Arp 220 with the Submillimeter Array (SMA) to determine the role magnetic fields play in the formation of stars. Credit: NASA/ESA/STScI/HST

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CfA astronomers are part of a team of researchers that have identified a key element in the formation of stars

Cambridge, MA - The missing ingredient for cooking up stars has been spotted for the first time by astronomers. Much like a pressure cooker has a weight on top of its lid to keep the pressure in, merging galaxies may need magnetic fields to create the ideal conditions for star formation.

Previously, the existence of such magnetic fields had only been theoretical. Now, an international team, including researchers from the Center for Astrophysics | Harvard & Smithsonian (CfA), has announced evidence of magnetic fields associated with a disk of gas and dust a few hundred light-years across deep inside a system of two merging galaxies known as Arp 220.

Arp 220 is one of the brightest objects beyond our Milky Way in infrared light. Astronomers think it is the result of a merger between two spiral galaxies full of gas, which has triggered great bursts of star formation.

Astronomers think disks of gas and dust could be the key to making the centers of interacting galaxies like Arp 220 just right for cooking lots of hydrogen gas into young stars. Magnetic fields may be able to stop intense bursts of star formation in the cores of merging galaxies from effectively ‘boiling over’ when the heat is turned up too high.

"This is the first time we’ve found evidence of magnetic fields in the core of a merger," said David Clements of Imperial College, United Kingdom who led the study, "but this discovery is just a starting point. We now need better models, and to see what's happening in other galaxy mergers."

Researchers used the Submillimeter Array (SMA) on Maunakea in Hawaii to probe deep inside Arp 220. Located near the summit of Maunakea on the Big Island of Hawaii, the SMA is one of the flagship observatories of the Smithsonian Astrophysical Observatory, which is part of the CfA, and consists of eight radio dishes working together as one telescope.

To form a lot of stars in a short period of time, a large amount of gas needs to squeeze together. As the heat from young stars builds, the gas gets dispersed, thereby inhibiting more stars from forming.

"To stop this happening, you need to add something to hold it all together – a magnetic field in a galaxy, or the lid and weight of a pressure cooker," added Clement.

Astronomers have long been looking for the magic ingredient that makes some galaxies form stars more efficiently than is normal. One of the issues about galaxy mergers is that they can form stars very quickly, in what is known as a starburst. This means they're behaving differently to other star forming galaxies in terms of the relationship between star formation rate and the mass of stars in the galaxy – they seem to be turning gas into stars more efficiently than non-starburst galaxies. Astronomers are baffled as to why this happens.

One possibility is that magnetic fields could act as an extra ‘binding force’ that holds the star forming gas together for longer, resisting the tendency for the gas to expand and dissipate as it is heated by young, hot stars, or by supernovae as massive stars die.

Theoretical models have previously suggested this, but the new observations are the first to show that magnetic fields are present in the case of at least one galaxy.

"Another effect of the magnetic field is that it slows down the rotation of gas in the disks of merging galaxies. This allows the force of gravity to take over, pulling the sluggish gas inward to fuel starbursts," said Qizhou Zhang of the CfA, a co-author of the study. "The SMA has been one of the leading telescopes for high angular resolution observations of magnetic fields in molecular clouds in the Milky Way. It's great to see that this study breaks new ground by measuring magnetic fields in merging galaxies."

The next step for the research team will be to search for magnetic fields in galaxies similar to Arp 220. With their result, and further observations, the researchers hope the role of magnetic fields in some of the most luminous galaxies in the local universe will become much clearer.

A paper revealing the discovery appeared in a recent issue of the Monthly Notices of the Royal Astronomical Society. It is available online at https://arxiv.org/abs/2412.14770

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Scientists Make First-Ever Detection of Mid-IR Flares in Sgr A*

This artist’s conception of the mid-IR flare in Sgr A* captures the variability, or changing intensity, of the flare as the black hole’s magnetic field lines approach each other. The byproduct of this magnetic reconnection is synchrotron emission. The emission seen in the flare intensifies as energized electrons travel along the SMBH’s magnetic field lines at close to the speed of light. The labels mark how the flare’s spectral index changes from the beginning to the end of the flare. Credit: CfA/Mel Weiss. High Resolution Image

This artist’s animated conception of the mid-IR flare in Sgr A* captures the variability, or changing intensity, of the flare as the black hole’s magnetic field lines approach each other. The byproduct of this magnetic reconnection is synchrotron emission. The emission seen in the flare intensifies as energized electrons travel along the SMBH’s magnetic field lines at close to the speed of light. Credit: CfA/Mel Weiss, Amy C. Oliver. Animation

This artist's conception of the mid-IR flare in Sgr A* captures the apparent movement of the flare as energized electrons spiral along the magnetic field lines of the supermassive black hole, and spike its intensity. These changes, or variability in intensity are known as synchrotron emission. Credit: CfA/Mel Weiss. High Resolution Image

This 360-degree panoramic image reveals the plane of our Milky Way Galaxy edge-on from our perspective on Earth, and provides an almost “outside looking in” view of its disk, and central bulge. Scientists have, for the first time ever, successfully observed a mid-IR flare in Sgr A*, the supermassive black hole that resides at the heart of the Milky Way. Credit: ESO, S. Brunier. High Resolution Image

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An international team of scientists, including multiple astronomers from CfA, have made the first-ever detection of a mid-IR flare from Sgr A*

National Harbor, MD - Using the James Webb Space Telescope (JWST), a team of scientists led by astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA) detected a Mid-Infrared (mid-IR) flare from the supermassive black hole (SMBH) at the heart of the Milky Way galaxy for the first time. In simultaneous observations, the team found a radio counterpart flare lagging behind.

Scientists have been actively observing Sgr A*— a SMBH roughly 4 million times the mass of the Sun— since the early 1990s. Sgr A* regularly exhibits flares that can be observed in multiple wavelengths, allowing scientists to see different views of the same flare. This characteristic also helps them understand how it emits flares and on what timescales they occur. Despite a long history of successful observations, including imaging of this cosmic beast by the Event Horizon Telescope in 2022, one crucial piece of the puzzle— mid-IR observations— was missing until now.

Infrared light is a type of electromagnetic radiation. It has longer wavelengths than visible light, but shorter wavelengths than radio light. Mid-IR sits in the middle of the IR spectrum, and allows astronomers to observe objects, such as flares, that are often difficult to observe in other wavelengths due to impenetrable dust. Until the recent study, no team had yet successfully detected Sgr A*’s variability in the mid-IR range, leaving a gap in scientists’ understanding of what causes flares and questions about whether their theoretical models are complete.

"Sgr A*’s flare evolves and changes quickly, in a matter of hours, and not all of these changes can be seen at every wavelength," said Joseph Michail, one of the lead authors on the paper and a NSF Astronomy and Astrophysics Postdoctoral Fellow at the Smithsonian Astrophysical Observatory, which is a part of the CfA. "For over 20 years, we’ve known what happens in the radio and Near-infrared (NIR) ranges, but the connection between them was never 100% clear. This new observation in mid-IR fills in that gap."

Scientists aren’t 100% sure what causes flares, so they rely on models and simulations, which they compare with observations to try to understand the cause. Many simulations suggest that the flares in Sgr A* are caused by the interaction of magnetic field lines in the SMBH’s turbulent accretion disk. When two magnetic field lines approach each other they can connect to each other and release a large amount of their energy. A byproduct of this magnetic reconnection is synchrotron emission. The emission seen in the flare intensifies as energized electrons travel along the SMBH’s magnetic field lines at close to the speed of light.

Michail said, "Because mid-IR sits between the submillimeter and the NIR, it was keeping secrets locked away about the role of electrons, which have to cool to release energy to power the flares. Our new observations are consistent with the existing models and simulations, giving us one more strong piece of evidence to support the theory of what’s behind the flares."

Simultaneous observations with the SAO’s Submillimeter Array— a facility of the CfA, NASA’s Chandra X-ray Observatory (which is operated by the SAO), and NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) filled in an additional part of the story. No flare was detected during the X-ray observations, likely because this particular flare didn’t accelerate electrons to energies as high as some other flares do. But the team hit paydirt when they turned to the SMA, which detected a millimeter (mm) flare lagging roughly 10 minutes behind the mid-IR flare.

"Our research indicates that there may be a connection between the observed mm-variability and the observed MIR flare emission," said Sebastiano D. von Fellenberg, a postdoctoral researcher at the Max Planck Institute for Radio Astronomy (MPIfR) and the " lead author of the new paper. He added that the results underscore the importance of expanding multi-wavelength studies of not just Sgr A*, but other SMBHs, like M87*, to get a clear picture of what’s really happening within and beyond their accretion disks.

"While our observations suggest that Sgr A*’s mid-IR emission does indeed result from synchrotron emission from cooling electrons, there’s more to understand about magnetic reconnection and the turbulence in Sgr A*’s accretion disk," said von Fellenberg. "This first-ever mid-IR detection, and the variability seen with the SMA, has not only filled a gap in our understanding of what has caused the flare in Sgr A* but has also opened a new line of important inquiry."

Michail added, "We still want to know, and need to find out… what other secrets is Sgr A* holding that the mid-IR can unlock? What’s really behind the flare’s variable emission? There’s a wealth of knowledge stored up inside this black hole’s region just waiting for us to access it."

The new observations were presented today in a press conference at the 245th proceedings of the American Astronomical Society (AAS) in National Harbor, Maryland, and are accepted for publication in the Astrophysical Journal Letters (ApJL) .

Located near the summit of Maunakea on the Big Island of Hawaii, the Submillimeter Array (SMA) is one of the flagship observatories of the CfA. The observatory consists of eight radio dishes working together as one telescope, giving astronomers a window on a wide range of astronomical objects and phenomena: planets and comets in our own Solar System; the birth of stars and planets; and the supermassive black holes hidden at the centers of the Milky Way and other galaxies. The SMA is operated jointly by the CfA and the Academia Sinica in Taiwan.

Another version of this press release was issued by the Max Planck Institute for Radio Astronomy (MPIfR).

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Resource:

von Fellenberg, S., Roychowdhury, T., Michail, J. et al. "First mid-infrared detection and modeling of a flare from Sgr A*," Astrophysical Journal Letters, arxiv:

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Amy C. Oliver
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Stellar Pyrotechnics on Display in Super Star Cluster

This image of Westerlund 1, one of the most massive young super star clusters in the Milky Way, combines data from JWST’s MIRI and NIRCam instruments to reveal detailed structures within the cluster's environment. The color image reveals intricate details of gas and dust in the cluster, with longer-wavelength mid-infrared emission (red) highlighting warm dust and gas, shorter mid-infrared emission (green) tracing complex structures of cooler dust and gas, and near-infrared emission (blue) showcasing the brilliant light of young, massive stars embedded in this cluster. These observations provide important insights into how stellar winds and radiation from massive stars interact with the surrounding material, shaping the cluster's morphology and influencing its evolution. North is 15 degrees to the right of up and east is to the left. Credit: D. Capela (University of Lisbon), M. G. Guarcello (INAF-OAPA) and the EWOCS team.High Resolution Image

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CfA astronomers help lead the study of an explosive cosmic fireworks show

National Harbor, MD - Astronomers have unveiled an explosive cosmic fireworks display of stars interacting with their environment. This dazzling spectacle – due to powerful winds flowing from the stars -- marks a major milestone in the ability to study the formation of the largest stars and to better understand how they affect their environments.

The researchers used NASA’s James Webb Space Telescope (JWST) to observe Westerlund 1, a so-called super star cluster with hundreds of very massive and potentially thousands of lower-mass young stars, with the Mid-Infrared Instrument (MIRI). Westerlund 1 is located across the Milky Way galaxy about 12,000 light-years from Earth.

The newly obtained JWST images of Westerlund 1 show many evolved, massive stars violently shedding their outer layers with bright patches throughout the image. These extended structures are known as ‘winds’ and show a surprising diversity in their shapes. The results provide details of the process where enormous amounts of energy from stellar winds and radiation are smashing into the local environment. This forms complex structures and stirs up the giant gas cloud, in which these stars are embedded.

"We were really surprised to see all these different wind structures in Westerlund 1, as we expected most of the gas and dust to be blown away by the highly energetic radiation emitted by the massive stars", says Kristina Monsch, a Smithsonian Astrophysical Observatory astronomer at the Center for Astrophysics | Harvard & Smithsonian, who helped lead the research. "The fact that there is so much dust and gas in Westerlund 1 suggests that massive stars play an important role in shaping their environments, possibly even influencing the formation of stars, similar to our Sun."

Westerlund 1 is one of the closest and most massive young star-forming clusters in our Galaxy, and it contains many rare supergiant and hypergiant stars, with masses ranging from eight to 100 times that of our Sun. Such stars live fast and die young with ages of only a few million years, which is in stark contrast to lower mass stars like our Sun that live for billions of years. Massive stars use up their hydrogen fuel much faster than lower mass stars, while at the same time losing most of their mass via winds and explosive outbursts from their outer layers, which JWST can observe at infrared wavelengths.

"Despite being rare star-forming environments in our Galaxy today, supermassive star clusters were very common in the early phases of the Universe," describes Mario Guarcello of INAF - Astronomical Observatory of Palermo in Italy, who led the JWST observing campaign. "Westerlund 1 is therefore one of the best testbeds for extending our knowledge of the formation of stars, especially the most massive ones. The observations simply look like a cosmic fireworks display; the data is showing us that many stars and planets are born in incredibly explosive environments."

Compared to the Sun, which will enter its red giant phase in five billion years or so, massive stars impact their local environments shortly after their formation, and eventually explode as energetic supernovae, leaving behind neutron stars or black holes. Only one supernova is expected to have gone off so far in Westerlund 1, however, more than 1,500 are expected over the next tens of million years.

"The discovery of these extended winds surrounding the massive stars in Westerlund 1 was only possible because we stared at the region for over six hours", says CfA astronomer Joshua Bennett Lovell who co-led the analysis of the JWST MIRI data. "But the time investment was worth the reward: we can now see a wide array of winds and ejecting material, vital clues to directly measure how young high-mass stars influence their surroundings."

”We pushed our detection limit down to the smallest stars that can form," explained Juan Rafael Martínez-Galarza, also from the CfA, who supported the MIRI data analysis. "Thus, we will be able to determine the true content of the cluster and to measure properties such as the mass distribution of its stars, down to the regime of the least massive stars in the cluster."

These results were presented today at a press conference at the annual winter meeting of the American Astronomical Society (AAS) in National Harbor, Maryland. A paper describing this work is being published in the Astronomy & Astrophysics journal and is available here.

The discoveries were made as part of the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, an international effort led by Mario G. Guarcello from the Palermo Astronomical Observatory (INAF) in Italy, aimed at studying the formation of stars and planets in the massive super star clusters Westerlund 1 and 2 using the James Webb Space Telescope and NASA’s Chandra X-ray Observatory.

Kristina Monsch and Joshua Bennett Lovell from the Center of Astrophysics | Harvard & Smithsonian (CfA) led the JWST MIRI data calibration of Westerlund 1, which revealed the extended gas structures emanating from the most massive stars in the cluster. Juan Rafael Martinez-Galarza and Konstantina Anastasopoulou, both researchers at the CfA and Jeremy J. Drake (Lockheed Martin), also played important roles in the analysis of these extensive datasets.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Media Contact:

Megan Watzke
Interim CfA Public Affairs Officer
Center for Astrophysics | Harvard & Smithsonian
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A Treasure Trove of Unseen Stars Seen Beyond the 'Dragon Arc'

Abell 370, a galaxy cluster located nearly 4 billion light-years away from Earth features several arcs of light, including the "Dragon Arc" (lower left of center). These arcs are caused by gravitational lensing: Light from distant galaxies far behind the massive galaxy cluster coming toward Earth is bent around Abell 370 by its massive gravity, resulting in contorted images.  Credit: NASA.High Resolution Image

The massive, yet invisible halo of dark matter of a galaxy cluster works as a "macrolens,", while lone, unbound stars drifting through the cluster act as additional "microlenses, multiplying the factor of magnification.  Credit: Yoshinobu Fudamoto. High Resolution Image

In this zoomed-in detail of the Hubble image of Abell 370, the host galaxy where the 44 stars were discovered appears several times: in a normal image (left), and a distorted image appearing as a drawn-out smear of light.  Credit: NASA. High Resolution Image

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An international team of astronomers took pictures of more than 40 individual stars in a galaxy so far away its light dates back to when the universe was only half its present age.

Cambridge, MA — Looking halfway across the observable universe and expecting to see individual stars is considered a non-starter in astronomy, a bit like raising a pair of binoculars at the moon in hopes of making out individual grains of dust inside its craters. Thanks to a cosmic quirk of nature, however, an international team of astronomers did just that.

Using NASA's James Webb Space Telescope (JWST), postdoctoral researcher Fengwu Sun at the Center for Astrophysics | Harvard & Smithsonian (CfA) and his team observed a galaxy nearly 6.5 billion light-years from Earth, at a time when the universe was half its current age. In this distant galaxy, the team identified 44 individual stars, made visible thanks to an effect known as gravitational lensing and JWST's high light collecting power.

Published in the journal Nature Astronomy, the discovery marks this record-breaking achievement – the largest number of individual stars detected in the distant universe. It also provides a way to investigate one of the universe's greatest mysteries – dark matter.

"This groundbreaking discovery demonstrates, for the first time, that studying large numbers of individual stars in a distant galaxy is possible," Sun, a co-author on the study, said. “While previous studies with the Hubble Space Telescope found around seven stars, we now have the capability to resolve stars that were previously outside of our capability. Importantly, observing more individual stars will also help us better understand dark matter in the lensing plane of these galaxies and stars, which we couldn’t do with only the handful of individual stars observed previously."

CfA's Sun found this treasure trove of stars while inspecting JWST images of a galaxy known as the Dragon Arc, located along the line of sight from Earth behind a massive cluster of galaxies called Abell 370. Due to its gravitational lensing effect, Abell 370 stretches the Dragon Arc's signature spiral into an elongated shape – like a hall of mirrors of cosmic proportions.

The research team carefully analyzed colors of each of the stars inside the Dragon Arc and found that many are red supergiants, similar to Betelgeuse in the constellation of Orion, which is in the final stages of its life. This contrasts with earlier discoveries, which predominantly identified blue "supergiants" similar to Rigel and Deneb, which are among the brightest stars in the night sky. According to the researchers, this difference in stellar types also highlights the unique power of JWST observations at infrared wavelengths that could reveal stars at lower temperatures.

"When we discovered these individual stars, we were actually looking for a background galaxy that is lensing-magnified by the galaxies in this massive cluster,” said Sun. “But when we processed the data, we realized that there were what appeared to be a lot of individual star points. It was an exciting find because it was the first time we were able to see so many individual stars so far away."

Sun, in particular, is excited for the next opportunity to study these red supergiants. "We know more about red supergiants in our local galactic neighborhood because they are closer and we can take better images and spectra, and sometimes even resolve the stars. We can use the knowledge we’ve gained from studying red supergiants in the local universe to interpret what happens next for them at such an early epoch of galaxy formation in future studies."

Most galaxies, including the Milky Way, contain tens of billions of stars. In nearby galaxies such as the Andromeda galaxy, astronomers can observe stars one by one. However, in galaxies billions of light-years away, stars appear blended together as their light needs to travel for billions of light-years before it reaches us, presenting a long-standing challenge to scientists studying how galaxies form and evolve.

"To us, galaxies that are very far away usually look like a diffuse, fuzzy blob," said lead study author Yoshinobu Fudamoto, an assistant professor at Chiba University in Japan. "But actually, those blobs consist of many, many individual stars. We just can't resolve them with our telescopes."

Recent advances in astronomy have opened new possibilities by leveraging gravitational lensing – a natural magnification effect caused by the strong gravitational fields of massive objects. As predicted by Albert Einstein, gravitational lenses can amplify the light of distant stars by factors of hundreds or even thousands, making them detectable with sensitive instruments like JWST.

"These findings have typically been limited to just one or two stars per galaxy," Fudamoto said. "To study stellar populations in a statistically meaningful way, we need many more observations of individual stars."

Future JWST observations are expected to capture more magnified stars in the Dragon Arc galaxy. These efforts could lead to detailed studies of hundreds of stars in distant galaxies. Moreover, observations of individual stars could provide insight into the structure of gravitational lenses and even shed light on the elusive nature of dark matter.

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News

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About the Center for Astrophysics | Harvard & Smithsonian

The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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Resource

Y. Fudamoto, F. Sun, et al, "More than Forty Gravitationally Magnified Stars in a Galaxy at Redshift of 0.725," Nature Astronomy., doi: 10.1038/s41550-024-02432-3

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Media Contact:

Amy C. Oliver
Public Affairs Officer, Fred Lawrence Whipple Observatory
Center for Astrophysics | Harvard & Smithsonian
amy.oliver@cfa.harvard.edu

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Astronomers Discover New Building Blocks of Complex Organic Matter

Credit: NSF/NSF NRAO/AUI/S. Dagnello

CfA scientists help detect a new molecule in interstellar space as list of identified complex molecules grows

The element carbon is a building block for life, both on Earth and potentially elsewhere in the vast reaches of space. There should be a lot of carbon in space, but surprisingly, it's not always easy to find.

While it can be observed in many places, it doesn’t add up to the volume astronomers would expect to see. The discovery of a new, complex molecule (1-cyanopyrene), challenges expectations about where the building blocks for carbon are found and how they evolve.

Astronomers have long understood that certain carbon-rich stars are soot factories that release copious quantities of small molecular sheets of carbon into the interstellar medium. Scientists thought, however, that these types of carbon-rich molecules could neither survive the harsh conditions of interstellar space nor be re-formed there by combustion-like chemistry because the temperature is far too low.

Researchers from the Center for Astrophysics | Harvard & Smithsonian (CfA) helped lead this research. A paper describing these results was published today in the journal Science.

“Our detection of 1-cyanopyrene gives us important new information about the chemical origin and fate of carbon -- the single most important element to complex chemistry both on Earth and in space,” said Bryan Changala of the CfA, a co-author of the Science paper.

The 1-cyanopyrene molecule is made up of multiple fused benzene rings. It belongs to a class of compounds known as Polycyclic Aromatic Hydrocarbons (PAHs), which were previously believed to form only at high temperatures in regions with lots of energy, like the environments surrounding aging stars. On Earth, PAHs are found in burning fossil fuels, and as char marks on grilled food.

Astronomers study PAHs not just to learn about their particular lifecycle, but to learn more about how they interact with and reveal more about the interstellar medium (ISM) and celestial bodies around them. PAHs are believed to be responsible for the unidentified infrared bands observed in many astronomical objects. These bands arise from the infrared fluorescence of PAHs after they absorb ultraviolet (UV) photons from stars. The intensity of these bands reveal PAHs could account for a significant fraction of carbon in the ISM.

However, the newly observed 1-cyanopyrene molecules were found in Taurus Molecular Cloud-1 (TMC-1), a cold interstellar cloud. Located in the Taurus constellation, TMC-1 has not yet begun forming stars, and the temperature is only about 10 degrees above absolute zero.

“TMC-1 is a natural laboratory for studying these molecules that go on to form the building blocks of stars and planets,” said Gabi Wenzel, a postdoctoral fellow at the Massachusetts Institute of Technology who led the lab work and is the first author on the Science paper.

“These are the largest molecules we’ve found in TMC-1 to date. This discovery pushes the boundaries of our understanding of the complexity of molecules that can exist in interstellar space,” said co-author Brett McGuire, an Assistant Professor of Chemistry at MIT and an adjunct astronomer at the National Science Foundation (NSF) National Radio Astronomy Observatory (NRAO).

Astronomers used the NSF Green Bank Telescope, the largest fully steerable radio telescope in the world, to discover 1-cyanopyrene. Every molecule has a unique rotational spectrum, like a fingerprint, which allows for its identification. However, their large size and lack of a permanent dipole moment, can make some PAHs difficult – or even impossible – to detect. The observations of cyanopyrene can provide indirect evidence for the presence of even larger and more complex molecules in future observations.

“Identifying the unique rotational spectrum of 1-cyanopyrene required the work of an interdisciplinary scientific team,” explains co-author Harshal Gupta, NSF Program Director for the Green Bank Observatory and Research Associate at the CfA. “This discovery is a great illustration of synthetic chemists, spectroscopists, astronomers, and modelers working closely and harmoniously.”

This research combined the expertise of astronomy and chemistry with measurements and analysis conducted in the molecular spectroscopy laboratory of Dr. Michael McCarthy at the CfA.

“The microwave spectrometers developed at the CfA are unique, world-class instruments specifically designed to measure the precise radio fingerprints of complex molecules like 1-cyanopyrene,” said McCarthy. “Predictions from even the most advanced quantum chemical theories are still thousands of times less accurate than what is needed to identify these molecules in space with radio telescopes, so experiments in laboratories like ours are indispensable to these ground-breaking astronomical discoveries."

Source: Harvard-Smithsonian Center for Astrophysics (CfA)/News Release

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The Center for Astrophysics | Harvard & Smithsonian is a collaboration between Harvard and the Smithsonian designed to ask—and ultimately answer—humanity's greatest unresolved questions about the nature of the universe. The Center for Astrophysics is headquartered in Cambridge, MA, with research facilities across the U.S. and around the world.

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