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Tag: Space Telescope Science Institute (STScI)

  • Dr. Jennifer Lotz Appointed Space Telescope Science Institute Director

    Dr. Jennifer Lotz Appointed Space Telescope Science Institute Director

    Newswise — The Association of Universities for Research in Astronomy (AURA) is pleased to announce the appointment of Dr. Jennifer Lotz as the Director of the Space Telescope Science Institute (STScI). Dr. Lotz will begin her five-year appointment as STScI Director starting February 12, 2024. Previously, Dr. Lotz was the Director of the International Gemini Observatory, which is operated by NSF’s NOIRLab and managed by AURA.

    “Dr. Lotz is a science driven, accomplished leader,” said Dr. Matt Mountain, President of AURA, which manages STScI on behalf of NASA. “Jen’s passion for the Institute’s mission, to enable the science community in its exploration of the ground-breaking science coming from both JWST and Hubble, and her compelling vision, will ensure an exciting future as she leads STScI into a new era of space science.”

    Dr. Lotz was chosen from a pool of highly qualified candidates by a selection committee of respected leaders in the field of astronomy. Her proven leadership skills as Director of Gemini Observatory, her research experience, and her knowledge of the challenges the field of astronomy faces were some of the qualifications that led to her selection as STScI’s next Director.  The Chair of AURA’s Board of Directors, Dr. Maura Hagan, added, “The AURA Board of Directors is thrilled with the selection of Jennifer Lotz as the next STScI Director. She represents a new generation of scientific leadership.”

    Dr. Lotz will succeed Dr. Nancy Levenson, who served as STScI Interim Director since August 2022. “I welcome Jen’s new perspectives and look forward to working with her to advance STScI,” said Dr. Levenson, who will return to her former position as STScI Deputy Director. AURA extends thanks to Dr. Levenson for her service as Interim Director.

    Dr. Lotz received her Ph.D. in astrophysics from Johns Hopkins University in 2003 and specializes in galaxy evolution and morphology, the high-redshift universe, and gravitational lensing. Before her appointment as Gemini Director, she was a tenured associate astronomer at STScI with a joint appointment as a research scientist at Johns Hopkins University. She was also a Leo Goldberg Fellow at the National Optical Astronomy Observatory, and a postdoctoral fellow at the University of California Santa Cruz.

    “I am honored to be rejoining STScI as its next Director. The Institute’s work on Hubble and JWST has been an inspiration for the world,” commented Jen Lotz. “I am also excited to partner with NASA to drive forward a new era of scientific discovery with the new generation of space telescopes — JWST, Roman, and the Habitable Worlds Observatory.”

    Lotz is a leading expert in the field of galaxy mergers, and makes use of both ground-based and space-based telescopes to track the growth of galaxies over cosmic time. She led the Hubble Frontier Fields program, one of the largest programs undertaken with Hubble to detect the faintest, most distant galaxies seen at that time. She continues her study of galaxies at the edge of the universe as part of the JWST Cosmic Evolution Early Release Science team.

    The Space Telescope Science Institute is expanding the frontiers of space astronomy by hosting the science operations center of the Hubble Space Telescope, the science and mission operations centers for the James Webb Space Telescope, and the science operations center for the Nancy Grace Roman Space Telescope. STScI also houses the Barbara A. Mikulski Archive for Space Telescopes (MAST) which is a NASA-funded project to support and provide to the astronomical community a variety of astronomical data archives, and is the data repository for the Hubble, Webb, Roman, Kepler, K2, TESS missions and more. STScI is operated by the Association of Universities for Research in Astronomy in Washington, D.C.

    The Association of Universities for Research in Astronomy (AURA), founded in 1957, is a consortium of 49 US institutions and 3 international affiliates. Although it began as a small organization with just eight founding members, AURA is now a thriving scientific institution with 52 members and over 1,700 employees. AURA’s role is to establish, nurture, and promote public observatories and facilities that advance innovative astronomical research. In addition, AURA is deeply committed to public and educational outreach, and to diversity throughout the astronomical and scientific workforce.

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  • The Crab Nebula Seen in New Light by NASA’s Webb

    The Crab Nebula Seen in New Light by NASA’s Webb

    Newswise — NASA’s James Webb Space Telescope has gazed at the Crab Nebula, a supernova remnant located 6,500 light-years away in the constellation Taurus. Since the recording of this energetic event in 1054 CE by 11th-century astronomers, the Crab Nebula has continued to draw attention and additional study as scientists seek to understand the conditions, behavior, and after-effects of supernovae through thorough study of the Crab, a relatively nearby example.

    Using Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument), a team led by Tea Temim at Princeton University is searching for answers about the Crab Nebula’s origins.

    “Webb’s sensitivity and spatial resolution allows us to accurately determine the composition of the ejected material, particularly the content of iron and nickel, which may reveal what type of explosion produced the Crab Nebula,” explained Temim.

    At first glance, the general shape of the supernova remnant is similar to the optical wavelength image released in 2005 from NASA’s Hubble Space Telescope: In Webb’s infrared observation, a crisp, cage-like structure of fluffy gaseous filaments are shown in red-orange. However, in the central regions, emission from dust grains (yellow-white and green) is mapped out by Webb for the first time.

    Additional aspects of the inner workings of the Crab Nebula become more prominent and are seen in greater detail in the infrared light captured by Webb. In particular, Webb highlights what is known as synchrotron radiation: emission produced from charged particles, like electrons, moving around magnetic field lines at relativistic speeds. The radiation appears here as milky smoke-like material throughout the majority of the Crab Nebula’s interior.

    This feature is a product of the nebula’s pulsar, a rapidly rotating neutron star. The pulsar’s strong magnetic field accelerates particles to extremely high speeds and causes them to emit radiation as they wind around magnetic field lines. Though emitted across the electromagnetic spectrum, the synchrotron radiation is seen in unprecedented detail with Webb’s NIRCam instrument.

    To locate the Crab Nebula’s pulsar heart, trace the wisps that follow a circular ripple-like pattern in the middle to the bright white dot in the center. Farther out from the core, follow the thin white ribbons of the radiation. The curvy wisps are closely grouped together, outlining the structure of the pulsar’s magnetic field, which sculpts and shapes the nebula.

    At center left and right, the white material curves sharply inward from the filamentary dust cage’s edges and goes toward the neutron star’s location, as if the waist of the nebula is pinched. This abrupt slimming may be caused by the confinement of the supernova wind’s expansion by a belt of dense gas.

    The wind produced by the pulsar heart continues to push the shell of gas and dust outward at a rapid pace. Among the remnant’s interior, yellow-white and green mottled filaments form large-scale loop-like structures, which represent areas where dust grains reside.

    The search for answers about the Crab Nebula’s past continues as astronomers further analyze the Webb data and consult previous observations of the remnant taken by other telescopes. Scientists will have newer Hubble data to review within the next year or so from the telescope’s reimaging of the supernova remnant. This will mark Hubble’s first look at emission lines from the Crab Nebula in over 20 years, and will enable astronomers to more accurately compare Webb and Hubble’s findings.

    For more information, including a video image tour, and to download full-resolution images, visit https://webbtelescope.org/contents/news-releases/2023/news-2023-137.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • NASA’s Webb Discovers New Feature in Jupiter’s Atmosphere

    NASA’s Webb Discovers New Feature in Jupiter’s Atmosphere

    Newswise — NASA’s James Webb Space Telescope has discovered a new, never-before-seen feature in Jupiter’s atmosphere. The high-speed jet stream, which spans more than 3,000 miles (4,800 kilometers) wide, sits over Jupiter’s equator above the main cloud decks. The discovery of this jet is giving insights into how the layers of Jupiter’s famously turbulent atmosphere interact with each other, and how Webb is uniquely capable of tracking those features.

    “This is something that totally surprised us,” said Ricardo Hueso of the University of the Basque Country in Bilbao, Spain, lead author on the paper describing the findings. “What we have always seen as blurred hazes in Jupiter’s atmosphere now appear as crisp features that we can track along with the planet’s fast rotation.”

    The research team analyzed data from Webb’s NIRCam (Near-Infrared Camera) captured in July 2022. The Early Release Science program – jointly led by Imke de Pater from the University of California, Berkeley and Thierry Fouchet from the Observatory of Paris – was designed to take images of Jupiter 10 hours apart, or one Jupiter day, in four different filters, each uniquely able to detect changes in small features at different altitudes of Jupiter’s atmosphere. 

    “Even though various ground-based telescopes, spacecraft like NASA’s Juno and Cassini, and NASA’s Hubble Space Telescope have observed the Jovian system’s changing weather patterns, Webb has already provided new findings on Jupiter’s rings, satellites, and its atmosphere,” de Pater noted.

    While Jupiter is different from Earth in many ways – Jupiter is a gas giant, Earth is a rocky, temperate world – both planets have layered atmospheres. Infrared, visible, radio, and ultraviolet-light wavelengths observed by these other missions detect the lower, deeper layers of the planet’s atmosphere – where gigantic storms and ammonia ice clouds reside.

    On the other hand, Webb’s look farther into the near-infrared than before is sensitive to the higher-altitude layers of the atmosphere, around 15-30 miles (25-50 kilometers) above Jupiter’s cloud tops. In near-infrared imaging, high-altitude hazes typically appear blurry, with enhanced brightness over the equatorial region. With Webb, finer details are resolved within the bright, hazy band.

    The newly discovered jet stream travels at about 320 miles per hour (515 kilometers per hour), twice the sustained winds of a Category 5 hurricane here on Earth. It is located around 25 miles (40 kilometers) above the clouds, in Jupiter’s lower stratosphere.

    By comparing the winds observed by Webb at high altitudes, to the winds observed at deeper layers from Hubble, the team could measure how fast the winds change with altitude and generate wind shears.

    While Webb’s exquisite resolution and wavelength coverage allowed for the detection of small cloud features used to track the jet, the complementary observations from Hubble taken one day after the Webb observations were also crucial to determine the base state of Jupiter’s equatorial atmosphere and observe the development of convective storms in Jupiter’s equator not connected to the jet.  

    “We knew the different wavelengths of Webb and Hubble would reveal the three-dimensional structure of storm clouds, but we were also able to use the timing of the data to see how rapidly storms develop,” added team member Michael Wong of the University of California, Berkeley, who led the associated Hubble observations.

    The researchers are looking forward to additional observations of Jupiter with Webb to determine if the jet’s speed and altitude change over time. 

    “Jupiter has a complicated but repeatable pattern of winds and temperatures in its equatorial stratosphere, high above the winds in the clouds and hazes measured at these wavelengths,” explained team member Leigh Fletcher of the University of Leicester in the United Kingdom. “If the strength of this new jet is connected to this oscillating stratospheric pattern, we might expect the jet to vary considerably over the next 2 to 4 years – it’ll be really exciting to test this theory in the years to come.”

    “It’s amazing to me that, after years of tracking Jupiter’s clouds and winds from numerous observatories, we still have more to learn about Jupiter, and features like this jet can remain hidden from view until these new NIRCam images were taken in 2022,” continued Fletcher.

    The researchers’ results were recently published in Nature Astronomy. 

    The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

    To learn more, visit https://webbtelescope.org/contents/news-releases/2023/news-2023-147.

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  • NASA’s Webb Detects Tiny Quartz Crystals in Clouds of Hot Gas Giant

    NASA’s Webb Detects Tiny Quartz Crystals in Clouds of Hot Gas Giant

    Newswise — Researchers using NASA’s James Webb Space Telescope have detected evidence for quartz nanocrystals in the high-altitude clouds of WASP-17 b, a hot Jupiter exoplanet 1,300 light-years from Earth. The detection, which was uniquely possible with MIRI (Webb’s Mid-Infrared Instrument), marks the first time that silica (SiO2) particles have been spotted in an exoplanet atmosphere.

    “We were thrilled!” said David Grant, a researcher at the University of Bristol in the UK and first author on a paper being published today in the Astrophysical Journal Letters. “We knew from Hubble observations that there must be aerosols – tiny particles making up clouds or haze – in WASP-17 b’s atmosphere, but we didn’t expect them to be made of quartz.”

    Silicates (minerals rich in silicon and oxygen) make up the bulk of Earth and the Moon as well as other rocky objects in our solar system, and are extremely common across the galaxy. But the silicate grains previously detected in the atmospheres of exoplanets and brown dwarfs appear to be made of magnesium-rich silicates like olivine and pyroxene, not quartz alone – which is pure SiO2.

    The result from this team, which also includes researchers from NASA’s Ames Research Center and NASA’s Goddard Space Flight Center, puts a new spin on our understanding of how exoplanet clouds form and evolve. “We fully expected to see magnesium silicates,” said co-author Hannah Wakeford, also from the University of Bristol. “But what we’re seeing instead are likely the building blocks of those, the tiny ‘seed’ particles needed to form the larger silicate grains we detect in cooler exoplanets and brown dwarfs.”

    Detecting Subtle Variations

    With a volume more than seven times that of Jupiter and a mass less than one-half of Jupiter, WASP-17 b is one of the largest and puffiest known exoplanets. This, along with its short orbital period of just 3.7 Earth-days, makes the planet ideal for transmission spectroscopy: a technique that involves measuring the filtering and scattering effects of a planet’s atmosphere on starlight.

    Webb observed the WASP-17 system for nearly 10 hours, collecting more than 1,275 brightness measurements of 5- to 12-micron mid-infrared light as the planet crossed its star. By subtracting the brightness of individual wavelengths of light that reached the telescope when the planet was in front of the star from those of the star on its own, the team was able to calculate the amount of each wavelength blocked by the planet’s atmosphere.

    What emerged was an unexpected “bump” at 8.6 microns, a feature that would not be expected if the clouds were made of magnesium silicates or other possible high-temperature aerosols like aluminum oxide, but which makes perfect sense if they are made of quartz.

    Crystals, Clouds, and Winds

    While these crystals are probably similar in shape to the pointy hexagonal prisms found in geodes and gem shops on Earth, each one is only about 10 nanometers across – one-millionth of one centimeter.

    “Hubble data actually played a key role in constraining the size of these particles,” explained co-author Nikole Lewis of Cornell University, who leads the Webb Guaranteed Time Observation (GTO) program designed to help build a three-dimensional view of a hot Jupiter atmosphere. “We know there is silica from Webb’s MIRI data alone, but we needed the visible and near-infrared observations from Hubble for context, to figure out how large the crystals are.”

    Unlike mineral particles found in clouds on Earth, the quartz crystals detected in the clouds of WASP-17 b are not swept up from a rocky surface. Instead, they originate in the atmosphere itself. “WASP-17 b is extremely hot – around 2,700 degrees Fahrenheit (1,500 degrees Celsius) – and the pressure where the quartz crystals form high in the atmosphere is only about one-thousandth of what we experience on Earth’s surface,” explained Grant. “In these conditions, solid crystals can form directly from gas, without going through a liquid phase first.”

    Understanding what the clouds are made of is crucial for understanding the planet as a whole. Hot Jupiters like WASP-17 b are made primarily of hydrogen and helium, with small amounts of other gases like water vapor (H2O) and carbon dioxide (CO2). “If we only consider the oxygen that is in these gases, and neglect to include all of the oxygen locked up in minerals like quartz (SiO2), we will significantly underestimate the total abundance,” explained Wakeford. “These beautiful silica crystals tell us about the inventory of different materials and how they all come together to shape the environment of this planet.”

    Exactly how much quartz there is, and how pervasive the clouds are, is hard to determine. “The clouds are likely present along the day/night transition (the terminator), which is the region that our observations probe,” said Grant. Given that the planet is tidally locked with a very hot day side and cooler night side, it is likely that the clouds circulate around the planet, but vaporize when they reach the hotter day side. “The winds could be moving these tiny glassy particles around at thousands of miles per hour.”

    WASP-17 b is one of three planets targeted by the JWST Telescope Scientist Team’s Deep Reconnaissance of Exoplanet Atmospheres using Multi-instrument Spectroscopy (DREAMS) investigations, which are designed to gather a comprehensive set of observations of one representative from each key class of exoplanets: a hot Jupiter, a warm Neptune, and a temperate rocky planet. The MIRI observations of hot Jupiter WASP-17 b were made as part of GTO program 1353.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

    Media Contacts:
    Margaret Carruthers / Christine Pulliam
    Space Telescope Science Institute, Baltimore, Md.
    [email protected]u / [email protected]

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  • Webb Detects Water Vapor in Rocky Planet-Forming Zone

    Webb Detects Water Vapor in Rocky Planet-Forming Zone

    Newswise — Water is essential for life as we know it. However, scientists debate how it reached the Earth and whether the same processes could seed rocky exoplanets orbiting distant stars. New insights may come from the planetary system PDS 70, located 370 light-years away. The star hosts both an inner disk and outer disk of gas and dust, separated by a 5 billion-mile-wide (8 billion kilometer) gap, and within that gap are two known gas-giant planets.

    New measurements by NASA’s James Webb Space Telescope’s MIRI (Mid-Infrared Instrument) have detected water vapor in the system’s inner disk, at distances of less than 100 million miles (160 million kilometers) from the star – the region where rocky, terrestrial planets may be forming. (The Earth orbits 93 million miles from our Sun.) This is the first detection of water in the terrestrial region of a disk already known to host two or more protoplanets.

    “We’ve seen water in other disks, but not so close in and in a system where planets are currently assembling. We couldn’t make this type of measurement before Webb,” said lead author Giulia Perotti of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany.

    “This discovery is extremely exciting, as it probes the region where rocky planets similar to Earth typically form,” added MPIA director Thomas Henning, a co-author on the paper. Henning is co-principal investigator of Webb’s MIRI (Mid-Infrared Instrument), which made the detection, and the principal investigator of the MINDS (MIRI Mid-Infrared Disk Survey) program that took the data.

    A Wet Environment for Forming Planets

    PDS 70 is a K-type star, cooler than our Sun, and is estimated to be 5.4 million years old. This is relatively old in terms of stars with planet-forming disks, which made the discovery of water vapor surprising.

    Over time, the gas and dust content of planet-forming disks declines. Either the central star’s radiation and winds blow out such material, or the dust grows into larger objects that eventually form planets. As previous studies failed to detect water in the central regions of similarly aged disks, astronomers suspected it might not survive the harsh stellar radiation, leading to a dry environment for the formation of any rocky planets.

    Astronomers haven’t yet detected any planets forming within the inner disk of PDS 70. However, they do see the raw materials for building rocky worlds in the form of silicates. The detection of water vapor implies that if rocky planets are forming there, they will have water available to them from the beginning.

    “We find a relatively high amount of small dust grains. Combined with our detection of water vapor, the inner disk is a very exciting place,” said co-author Rens Waters of Radboud University in The Netherlands.

    What is the Water’s Origin?

    The discovery raises the question of where the water came from. The MINDS team considered two different scenarios to explain their finding.

    One possibility is that water molecules are forming in place, where we detect them, as hydrogen and oxygen atoms combine. A second possibility is that ice-coated dust particles are being transported from the cool outer disk to the hot inner disk, where the water ice sublimates and turns into vapor. Such a transport system would be surprising, since the dust would have to cross the large gap carved out by the two giant planets.

    Another question raised by the discovery is how water could survive so close to the star, when the star’s ultraviolet light should break apart any water molecules. Most likely, surrounding material such as dust and other water molecules serves as a protective shield. As a result, the water detected in the inner disk of PDS 70 could survive destruction.

    Ultimately, the team will use two more of Webb’s instruments, NIRCam (Near-Infrared Camera) and NIRSpec (Near-Infrared Spectrograph) to study the PDS 70 system in an effort to glean an even greater understanding.

    These observations were taken as part of Guaranteed Time Observation program 1282. This finding has been published in the journal Nature.

    For more information or to download full-resolution images, visit https://webbtelescope.org/contents/news-releases/2023/news-2023-130

    The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

    Media Contacts:

    Christine Pulliam
    Space Telescope Science Institute, Baltimore, Md.
    [email protected]

    Markus Nielbock
    Max Planck Institute for Astronomy, Heidelberg, Germany
    [email protected]

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  • Webb Celebrates First Year of Science With Close-up on Birth of Sun-like Stars

    Webb Celebrates First Year of Science With Close-up on Birth of Sun-like Stars

    Newswise — From our cosmic backyard in the solar system to distant galaxies near the dawn of time, NASA’s James Webb Space Telescope has delivered on its promise of revealing the universe like never before in its first year of science operations. To celebrate the completion of a successful first year, NASA has released Webb’s image of a small star-forming region in the Rho Ophiuchi cloud complex.

    “In just one year, the James Webb Space Telescope has transformed humanity’s view of the cosmos, peering into dust clouds and seeing light from faraway corners of the universe for the very first time. Every new image is a new discovery, empowering scientists around the globe to ask and answer questions they once could never dream of,” said NASA Administrator Bill Nelson. “Webb is an investment in American innovation but also a scientific feat made possible with NASA’s international partners that share a can-do spirit to push the boundaries of what is known to be possible. Thousands of engineers, scientists, and leaders poured their life’s passion into this mission, and their efforts will continue to improve our understanding of the origins of the universe – and our place in it.”

    The new Webb image released today features the nearest star-forming region to us. Its proximity at 390 light-years allows for a highly detailed close-up, with no foreground stars in the intervening space.

    “On its first anniversary, the James Webb Space Telescope has already delivered upon its promise to unfold the universe, gifting humanity with a breathtaking treasure trove of images and science that will last for decades,” said Nicola Fox, associate administrator of NASA’s Science Mission Directorate in Washington. “An engineering marvel built by the world’s leading scientists and engineers, Webb has given us a more intricate understanding of galaxies, stars, and the atmospheres of planets outside of our solar system than ever before, laying the groundwork for NASA to lead the world in a new era of scientific discovery and the search for habitable worlds.”

    Webb’s image shows a region containing approximately 50 young stars, all of them similar in mass to the Sun, or smaller. The darkest areas are the densest, where thick dust cocoons still-forming protostars. Huge bipolar jets of molecular hydrogen, represented in red, dominate the image, appearing horizontally across the upper third and vertically on the right. These occur when a star first bursts through its natal envelope of cosmic dust, shooting out a pair of opposing jets into space like a newborn first stretching her arms out into the world. In contrast, the star S1 has carved out a glowing cave of dust in the lower half of the image. It is the only star in the image that is significantly more massive than the Sun.

    “Webb’s image of Rho Ophiuchi allows us to witness a very brief period in the stellar lifecycle with new clarity. Our own Sun experienced a phase like this, long ago, and now we have the technology to see the beginning of another star’s story,” said Klaus Pontoppidan, who served as Webb project scientist at the Space Telescope Science Institute in Baltimore, Maryland, since before the telescope’s launch and through the first year of operations.

    Some stars in the image display tell-tale shadows indicating protoplanetary disks – potential future planetary systems in the making. Discover more details in the image video tour, or explore yourself in the zoomable image.

    A Full Year, Across the Full Sky

    From its very first deep field image, unveiled by President Joe Biden, Vice President Kamala Harris, and Nelson live at the White House, Webb has delivered on its promise to show us more of the universe than ever before. However, Webb revealed much more than distant galaxies in the early universe.

    “The breadth of science Webb is capable of exploring really becomes clear now, when we have a full year’s worth of data from targets across the sky,” said Eric Smith, associate director for research in the Astrophysics Division at NASA Headquarters and Webb program scientist. “Webb’s first year of science has not only taught us new things about our universe, but it has revealed the capabilities of the telescope to be greater than our expectations, meaning future discoveries will be even more amazing.” The global astronomy community has spent the past year excitedly poring over Webb’s initial public data and getting a feel for how to work with it.

    Beyond the stunning infrared images, what really has scientists excited are Webb’s crisp spectra – the detailed information that can be gleaned from light by the telescope’s spectroscopic instruments. Webb’s spectra have confirmed the distances of some of the farthest galaxies ever observed, and have discovered the earliest, most distant supermassive black holes. They have identified the compositions of planet atmospheres (or lack thereof) with more detail than ever before, and have narrowed down what kinds of atmospheres may exist on rocky exoplanets for the first time. They also have revealed the chemical makeup of stellar nurseries and protoplanetary disks, detecting water, organic carbon-containing molecules, and more. Already, Webb observations have resulted in hundreds of scientific papers answering longstanding questions and raising new ones to address with Webb.

    The breadth of Webb science is also apparent in its observations of the region of space we are most familiar with – our own solar system. Faint rings of gas giants appear out of the darkness, dotted by moons, while in the background Webb shows distant galaxies. By comparing detections of water and other molecules in our solar system with those found in the disks of other, much younger planetary systems, Webb is helping to build up clues about our own origins – how Earth became the ideal place for life as we know it.

    “With a year of science under our belts, we know exactly how powerful this telescope is, and have delivered a year of spectacular data and discoveries,” said Webb senior project scientist Jane Rigby of NASA’s Goddard Space Flight Center. “We’ve selected an ambitious set of observations for year two that builds on everything we’ve learned so far. Webb’s science mission is just getting started — there’s so much more to come.”

    For more information or to download full-resolution images and videos, visit https://webbtelescope.org/contents/news-releases/2023/news-2023-128

    The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • Webb Locates Dust Reservoirs in Two Supernovae

    Webb Locates Dust Reservoirs in Two Supernovae

    Newswise — Researchers using NASA’s James Webb Space Telescope have made major strides in confirming the source of dust in early galaxies. Observations of two Type II supernovae, Supernova 2004et (SN 2004et) and Supernova 2017eaw (SN 2017eaw), have revealed large amounts of dust within the ejecta of each of these objects. The mass found by researchers supports the theory that supernovae played a key role in supplying dust to the early universe.

    Dust is a building block for many things in our universe – planets in particular. As dust from dying stars spreads through space, it carries essential elements to help give birth to the next generation of stars and their planets. Where that dust comes from has puzzled astronomers for decades. One significant source of cosmic dust could be supernovae – after the dying star explodes, its leftover gas expands and cools to create dust.

    “Direct evidence of this phenomenon has been slim up to this point, with our capabilities only allowing us to study the dust population in one relatively nearby supernova to date – Supernova 1987A, 170,000 light-years away from Earth,” said lead author Melissa Shahbandeh of Johns Hopkins University and the Space Telescope Science Institute in Baltimore, Maryland. “When the gas cools enough to form dust, that dust is only detectable at mid-infrared wavelengths provided you have enough sensitivity.”

    For supernovae more distant than SN 1987A like SN 2004et and SN 2017eaw, both in NGC 6946 about 22 million light-years away, that combination of wavelength coverage and exquisite sensitivity can only be obtained with Webb’s MIRI (Mid-Infrared Instrument).

    The Webb observations are the first breakthrough in the study of dust production from supernovae since the detection of newly formed dust in SN 1987A with the Atacama Large Millimeter/submillimeter Array (ALMA) telescope nearly a decade ago. 

    Another particularly intriguing result of their study isn’t just the detection of dust, but the amount of dust detected at this early stage in the supernova’s life. In SN 2004et, the researchers found more than 5,000 Earth masses of dust.

    “When you look at the calculation of how much dust we’re seeing in SN 2004et especially, it rivals the measurements in SN 1987A, and it’s only a fraction of the age,” added program lead Ori Fox of the Space Telescope Science Institute. “It’s the highest dust mass detected in supernovae since SN 1987A.” 

    Observations have shown astronomers that young, distant galaxies are full of dust, but these galaxies are not old enough for intermediate-mass stars, like the Sun, to have supplied the dust as they age. More massive, short-lived stars could have died soon enough and in large enough numbers to create that much dust. 

    While astronomers have confirmed that supernovae produce dust, the question has lingered about how much of that dust can survive the internal shocks reverberating in the aftermath of the explosion. Seeing this amount of dust at this stage in the lifetimes of SN 2004et and SN 2017eaw suggests that dust can survive the shockwave – evidence that supernovae really are important dust factories after all.

    Researchers also note that the current estimations of the mass may be the tip of the iceberg. While Webb has allowed researchers to measure dust cooler than ever before, there may be undetected, colder dust radiating even farther into the electromagnetic spectrum that remains obscured by the outermost layers of dust.

    The researchers emphasized that the new findings are also just a hint at newfound research capabilities into supernovae and their dust production using Webb, and what that can tell us about the stars from which they came. 

    “There’s a growing excitement to understand what this dust also implies about the core of the star that exploded,” Fox said. “After looking at these particular findings, I think our fellow researchers are going to be thinking of innovative ways to work with these dusty supernovae in the future.”

    SN 2004et and SN2017eaw are the first of five targets included in this program. The observations were completed as part of Webb General Observer program 2666. The paper was published in the Monthly Notices of the Royal Astronomical Society on July 5.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency), and CSA (Canadian Space Agency).

    For more information, please visit https://webbtelescope.org/contents/news-releases/2023/news-2023-115. 

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  • NASA’s Webb Spots Swirling, Gritty Clouds on Remote Planet

    NASA’s Webb Spots Swirling, Gritty Clouds on Remote Planet

    Newswise — Researchers observing with NASA’s James Webb Space Telescope have pinpointed silicate cloud features in a distant planet’s atmosphere. The atmosphere is constantly rising, mixing, and moving during its 22-hour day, bringing hotter material up and pushing colder material down. The resulting brightness changes are so dramatic that it is the most variable planetary-mass object known to date. The team, led by Brittany Miles of the University of Arizona, also made extraordinarily clear detections of water, methane and carbon monoxide with Webb’s data, and found evidence of carbon dioxide. This is the largest number of molecules ever identified all at once on a planet outside our solar system.

    Cataloged as VHS 1256 b, the planet is about 40 light-years away and orbits not one, but two stars over a 10,000-year period. “VHS 1256 b is about four times farther from its stars than Pluto is from our Sun, which makes it a great target for Webb,” Miles said. “That means the planet’s light is not mixed with light from its stars.” Higher up in its atmosphere, where the silicate clouds are churning, temperatures reach a scorching 1,500 degrees Fahrenheit (830 degrees Celsius).

    Within those clouds, Webb detected both larger and smaller silicate dust grains, which are shown on a spectrum. “The finer silicate grains in its atmosphere may be more like tiny particles in smoke,” noted co-author Beth Biller of the University of Edinburgh in Scotland. “The larger grains might be more like very hot, very small sand particles.”

    VHS 1256 b has low gravity compared to more massive brown dwarfs, which means that its silicate clouds can appear and remain higher in its atmosphere where Webb can detect them. Another reason its skies are so turbulent is the planet’s age. In astronomical terms, it’s quite young. Only 150 million years have passed since it formed – and it will continue to change and cool over billions of years.

    In many ways, the team considers these findings to be the first “coins” pulled out of a spectrum that researchers view as a treasure chest of data. In many ways, they’ve only begun identifying its contents. “We’ve identified silicates, but better understanding which grain sizes and shapes match specific types of clouds is going to take a lot of additional work,” Miles said. “This is not the final word on this planet – it is the beginning of a large-scale modeling effort to fit Webb’s complex data.”

    Although all of the features the team observed have been spotted on other planets elsewhere in the Milky Way by other telescopes, other research teams typically identified only one at a time. “No other telescope has identified so many features at once for a single target,” said co-author Andrew Skemer of the University of California, Santa Cruz. “We’re seeing a lot of molecules in a single spectrum from Webb that detail the planet’s dynamic cloud and weather systems.”

    The team came to these conclusions by analyzing data known as spectra gathered by two instruments aboard Webb, the Near-Infrared Spectrograph (NIRSpec) and the Mid-Infrared Instrument (MIRI). Since the planet orbits at such a great distance from its stars, the researchers were able to observe it directly, rather than using the transit technique or a coronagraph to take these data.

    There will be plenty more to learn about VHS 1256 b in the months and years to come as this team – and others – continue to sift through Webb’s high-resolution infrared data. “There’s a huge return on a very modest amount of telescope time,” Biller added. “With only a few hours of observations, we have what feels like unending potential for additional discoveries.”

    What might become of this planet billions of years from now? Since it’s so far from its stars, it will become colder over time, and its skies may transition from cloudy to clear.

    The researchers observed VHS 1256 b as part of Webb’s Early Release Science program, which is designed to help transform the astronomical community’s ability to characterize planets and the disks where they form.

    The team’s paper, entitled “The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b,” will be published in The Astrophysical Journal Letters on March 22.

    For high-resolution imagery, visit https://webbtelescope.org/contents/news-releases/2023/news-2023-105

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • NASA’s Webb Uncovers New Details in Pandora’s Cluster

    NASA’s Webb Uncovers New Details in Pandora’s Cluster

    Newswise — Astronomers have revealed the latest deep field image from NASA’s James Webb Space Telescope, featuring never-before-seen details in a region of space known as Pandora’s Cluster (Abell 2744). Webb’s view displays three clusters of galaxies – already massive – coming together to form a megacluster. The combined mass of the galaxy clusters creates a powerful gravitational lens, a natural magnification effect of gravity, allowing much more distant galaxies in the early universe to be observed by using the cluster like a magnifying glass.

    Only Pandora’s central core has previously been studied in detail by NASA’s Hubble Space Telescope. By combining Webb’s powerful infrared instruments with a broad mosaic view of the region’s multiple areas of lensing, astronomers aimed to achieve a balance of breadth and depth that will open up a new frontier in the study of cosmology and galaxy evolution.

    “The ancient myth of Pandora is about human curiosity and discoveries that delineate the past from the future, which I think is a fitting connection to the new realms of the universe Webb is opening up, including this deep-field image of Pandora’s Cluster,” said astronomer Rachel Bezanson of the University of Pittsburgh in Pennsylvania, co-principal investigator on the “Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization” (UNCOVER) program to study the region.

    “When the images of Pandora’s Cluster first came in from Webb, we were honestly a little star struck,” said Bezanson. “There was so much detail in the foreground cluster and so many distant lensed galaxies, I found myself getting lost in the image. Webb exceeded our expectations.” The new view of Pandora’s Cluster stitches four Webb snapshots together into one panoramic image, displaying roughly 50,000 sources of near-infrared light.

    In addition to magnification, gravitational lensing distorts the appearance of distant galaxies, so they look very different than those in the foreground. The galaxy cluster “lens” is so massive that it warps the fabric of space itself, enough for light from distant galaxies that passes through that warped space to also take on a warped appearance.

    Astronomer Ivo Labbe of the Swinburne University of Technology in Melbourne, Australia, co-principal investigator on the UNCOVER program, said that in the lensing core to the lower right in the Webb image, which has never been imaged by Hubble, Webb revealed hundreds of distant lensed galaxies that appear like faint arced lines in the image. Zooming in on the region reveals more and more of them.

    “Pandora’s Cluster, as imaged by Webb, shows us a stronger, wider, deeper, better lens than we have ever seen before,” Labbe said. “My first reaction to the image was that it was so beautiful, it looked like a galaxy formation simulation. We had to remind ourselves that this was real data, and we are working in a new era of astronomy now.”

    The UNCOVER team used Webb’s Near-Infrared Camera (NIRCam) to capture the cluster with exposures lasting 4-6 hours, for a total of about 30 hours of observing time. The next step is to meticulously go through the imaging data and select galaxies for follow-up observation with the Near-Infrared Spectrograph (NIRSpec), which will provide precise distance measurements, along with other detailed information about the lensed galaxies’ compositions, providing new insights into the early era of galaxy assembly and evolution. The UNCOVER team expects to make these NIRSpec observations in the summer of 2023.

    In the meantime, all of the NIRCam photometric data has been publicly released so that other astronomers can become familiar with it and plan their own scientific studies with Webb’s rich datasets. “We are committed to helping the astronomy community make the best use of the fantastic resource we have in Webb,” said UNCOVER co-investigator Gabriel Brammer of the Niels Bohr Institute’s Cosmic Dawn Center at the University of Copenhagen. “This is just the beginning of all the amazing Webb science to come.”

    The imaging mosaics and catalog of sources on Pandora’s Cluster (Abell 2744) provided by the UNCOVER team combine publicly available Hubble data with Webb photometry from three early observation programs: JWST-GO-2561, JWST-DD-ERS-1324, and JWST-DD-2756.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • Webb Detects Extremely Small Main Belt Asteroid

    Webb Detects Extremely Small Main Belt Asteroid

    Newswise — An asteroid roughly the size of Rome’s Colosseum — between 300 to 650 feet (100 to 200 meters) in length — has been detected by an international team of European astronomers using NASA’s James Webb Space Telescope. Their project used data from the calibration of the Mid-InfraRed Instrument (MIRI), in which the team serendipitously detected an interloping asteroid. The object is likely the smallest observed to date by Webb and may be an example of an object measuring under 0.6 miles (1 kilometer) in length within the main asteroid belt, located  between Mars and Jupiter. More observations are needed to better characterize this object’s nature and properties.

    “We — completely unexpectedly — detected a small asteroid in publicly available MIRI calibration observations,” explained Thomas Müller, an astronomer at the Max Planck Institute for Extraterrestrial Physics in Germany. “The measurements are some of the first MIRI measurements targeting the ecliptic plane and our work suggests that many new objects will be detected with this instrument.”

    These Webb observations, published in the journal Astronomy and Astrophysics, were not designed to hunt for new asteroids — in fact, they were calibration images of the main belt asteroid (10920) 1998 BC1, which astronomers discovered in 1998. The observations were conducted to test the performance of some of MIRI’s filters, but the calibration team considered them to have failed for technical reasons due to the brightness of the target and an offset telescope pointing. Despite this, the data on asteroid 10920 were used by the team to establish and test a new technique to constrain an object’s orbit and to estimate its size. The validity of the method was demonstrated for asteroid 10920 using the MIRI observations combined with data from ground-based telescopes and ESA’s Gaia mission.

    In the course of the analysis of the MIRI data, the team found the smaller interloper in the same field of view. The team’s results suggest the object measures 100–200 meters, occupies a very low-inclination orbit, and was located in the inner main-belt region at the time of the Webb observations.

    “Our results show that even ‘failed’ Webb observations can be scientifically useful, if you have the right mindset and a little bit of luck,” elaborated Müller. “Our detection lies in the main asteroid belt, but Webb’s incredible sensitivity made it possible to see this roughly 100-meter object at a distance of more than 100 million kilometers.”

    The detection of this asteroid — which the team suspects to be the smallest observed to date by Webb and one of the smallest detected in the main belt — would, if confirmed as a new asteroid discovery, have important implications for our understanding of the formation and evolution of the solar system. Current models predict the occurrence of asteroids down to very small sizes, but small asteroids have been studied in less detail than their larger counterparts owing to the difficulty of observing these objects. Future dedicated Webb observations will allow astronomers to study asteroids smaller than 1 kilometer in size.

    What’s more, this result suggests that Webb will also be able to serendipitously contribute to the detection of new asteroids. The team suspects that even short MIRI observations close to the plane of the solar system will always include a few asteroids, most of which will be unknown objects.

    In order to confirm that the object detected is a newly discovered asteroid, more position data relative to background stars is required from follow-up studies to constrain the object’s orbit.
     
    “This is a fantastic result which highlights the capabilities of MIRI to serendipitously detect a previously undetectable size of asteroid in the main belt,” concluded Bryan Holler, Webb support scientist at the Space Telescope Science Institute in Baltimore, Maryland. “Repeats of these observations are in the process of being scheduled, and we are fully expecting new asteroid interlopers in those images.”

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • Webb Unveils Dark Side of Pre-stellar Ice Chemistry

    Webb Unveils Dark Side of Pre-stellar Ice Chemistry

    Newswise — If you want to build a habitable planet, ices are a vital ingredient because they are the main source of several key elements — namely carbon, hydrogen, oxygen, nitrogen, and sulfur (referred to here as CHONS). These elements are important ingredients in both planetary atmospheres and molecules like sugars, alcohols, and simple amino acids.

    An international team of astronomers using NASA’s James Webb Space Telescope has obtained an in-depth inventory of the deepest, coldest ices measured to date in a molecular cloud. In addition to simple ices like water, the team was able to identify frozen forms of a wide range of molecules, from carbonyl sulfide, ammonia, and methane, to the simplest complex organic molecule, methanol. (The researchers considered organic molecules to be complex when having six or more atoms.) This is the most comprehensive census to date of the icy ingredients available to make future generations of stars and planets, before they are heated during the formation of young stars.

    “Our results provide insights into the initial, dark chemistry stage of the formation of ice on the interstellar dust grains that will grow into the centimeter-sized pebbles from which planets form in disks,” said Melissa McClure, an astronomer at Leiden Observatory in the Netherlands, who is the principal investigator of the observing program and lead author of the paper describing this result. “These observations open a new window on the formation pathways for the simple and complex molecules that are needed to make the building blocks of life.”

    In addition to the identified molecules, the team found evidence for molecules more complex than methanol, and, although they didn’t definitively attribute these signals to specific molecules, this proves for the first time that complex molecules form in the icy depths of molecular clouds before stars are born.

    “Our identification of complex organic molecules, like methanol and potentially ethanol, also suggests that the many star and planetary systems developing in this particular cloud will inherit molecules in a fairly advanced chemical state,” added Will Rocha, an astronomer at Leiden Observatory who contributed to this discovery. “This could mean that the presence of precursors to prebiotic molecules in planetary systems is a common result of star formation, rather than a unique feature of our own solar system.”
     
    By detecting the sulfur-bearing ice carbonyl sulfide, the researchers were able to estimate the amount of sulfur embedded in icy pre-stellar dust grains for the first time. While the amount measured is larger than previously observed, it is still less than the total amount expected to be present in this cloud, based on its density. This is true for the other CHONS elements as well. A key challenge for astronomers is understanding where these elements are hiding: in ices, soot-like materials, or rocks. The amount of CHONS in each type of material determines how much of these elements end up in exoplanet atmospheres and how much in their interiors.
     
    “The fact that we haven’t seen all of the CHONS that we expect may indicate that they are locked up in more rocky or sooty materials that we cannot measure,” explained McClure. “This could allow a greater diversity in the bulk composition of terrestrial planets.”

    Chemical characterization of the ices was accomplished by studying how starlight from beyond the molecular cloud was absorbed by icy molecules within the cloud at specific infrared wavelengths visible to Webb. This process leaves behind chemical fingerprints known as absorption lines which can be compared with laboratory data to identify which ices are present in the molecular cloud. In this study, the team targeted ices buried in a particularly cold, dense, and difficult-to-investigate region of the Chamaeleon I molecular cloud, a region roughly 500 light-years from Earth which is currently in the process of forming dozens of young stars.
     
    “We simply couldn’t have observed these ices without Webb,” elaborated Klaus Pontoppidan, Webb project scientist at the Space Telescope Science Institute in Baltimore, Maryland, who was involved in this research. “The ices show up as dips against a continuum of background starlight. In regions that are this cold and dense, much of the light from the background star is blocked, and Webb’s exquisite sensitivity was necessary to detect the starlight and therefore identify the ices in the molecular cloud.”
     
    This research forms part of the Ice Age project, one of Webb’s 13 Early Release Science programs. These observations are designed to showcase Webb’s observing capabilities and to allow the astronomical community to learn how to get the best from its instruments. The Ice Age team has already planned further observations, and hopes to trace out the journey of ices from their formation through to the assemblage of icy comets.
     
    “This is just the first in a series of spectral snapshots that we will obtain to see how the ices evolve from their initial synthesis to the comet-forming regions of protoplanetary disks,” concluded McClure. “This will tell us which mixture of ices — and therefore which elements — can eventually be delivered to the surfaces of terrestrial exoplanets or incorporated into the atmospheres of giant gas or ice planets.”

    These results were published in the Jan. 23 issue of Nature Astronomy.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

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  • Hubble Finds Hungry Black Hole Twisting Captured Star Into Donut Shape

    Hubble Finds Hungry Black Hole Twisting Captured Star Into Donut Shape

    FOR RELEASE: 5:15 p.m. (EST) January 12, 2023

    RELEASE: STScI-PR2023-001

     

    Newswise — Black holes are gatherers, not hunters. They lie in wait until a hapless star wanders by. When the star gets close enough, the black hole’s gravitational grasp violently rips it apart and sloppily devours its gasses while belching out intense radiation.

    Astronomers using NASA’s Hubble Space Telescope have recorded a star’s final moments in detail as it gets gobbled up by a black hole.

    These are termed “tidal disruption events.” But the wording belies the complex, raw violence of a black hole encounter. There is a balance between the black hole’s gravity pulling in star stuff, and radiation blowing material out. In other words, black holes are messy eaters. Astronomers are using Hubble to find out the details of what happens when a wayward star plunges into the gravitational abyss.

    Hubble can’t photograph the AT2022dsb tidal event’s mayhem up close, since the munched-up star is nearly 300 million light-years away at the core of the galaxy ESO 583-G004. But astronomers used Hubble’s powerful ultraviolet sensitivity to study the light from the shredded star, which include hydrogen, carbon, and more. The spectroscopy provides forensic clues to the black hole homicide.

    About 100 tidal disruption events around black holes have been detected by astronomers using various telescopes. NASA recently reported that several of its high-energy space observatories spotted another black hole tidal disruption event on March 1, 2021, and it happened in another galaxy. Unlike Hubble observations, data was collected in X-ray light from an extremely hot corona around the black hole that formed after the star was already torn apart.

    “However, there are still very few tidal events that are observed in ultraviolet light given the observing time. This is really unfortunate because there’s a lot of information that you can get from the ultraviolet spectra,” said Emily Engelthaler of the Center for Astrophysics | Harvard & Smithsonian (CfA) in Cambridge, Massachusetts. “We’re excited because we can get these details about what the debris is doing. The tidal event can tell us a lot about a black hole.” Changes in the doomed star’s condition are taking place on the order of days or months.

    For any given galaxy with a quiescent supermassive black hole at the center, it’s estimated that the stellar shredding happens only a few times in every 100,000 years.

    This AT2022dsb stellar snacking event was first caught on March 1, 2022 by the All-Sky Automated Survey for Supernovae (ASAS-SN or “Assassin”), a network of ground-based telescopes that surveys the extragalactic sky roughly once a week for violent, variable, and transient events that are shaping our universe. This energetic collision was close enough to Earth and bright enough for the Hubble astronomers to do ultraviolet spectroscopy over a longer than normal period of time.

    “Typically, these events are hard to observe. You get maybe a few observations at the beginning of the disruption when it’s really bright. Our program is different in that it is designed to look at a few tidal events over a year to see what happens,” said Peter Maksym of the CfA. “We saw this early enough that we could observe it at these very intense black hole accretion stages. We saw the accretion rate drop as it turned to a trickle over time.”

    The Hubble spectroscopic data are interpreted as coming from a very bright, hot, donut-shaped area of gas that was once the star. This area, known as a torus, is the size of the solar system and is swirling around a black hole in the middle.

    “We’re looking somewhere on the edge of that donut. We’re seeing a stellar wind from the black hole sweeping over the surface that’s being projected towards us at speeds of 20 million miles per hour (three percent the speed of light),” said Maksym. “We really are still getting our heads around the event. You shred the star and then it’s got this material that’s making its way into the black hole. And so you’ve got models where you think you know what is going on, and then you’ve got what you actually see. This is an exciting place for scientists to be: right at the interface of the known and the unknown.”

    The results were reported during a press conference on Jan. 12 at the 241st meeting of the American Astronomical Society in Seattle, Washington. 

    The Hubble Space Telescope is a project of international cooperation between NASA and ESA. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble and Webb science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.

    For an artist’s illustration and more information about this study and Hubble, visit:

    https://hubblesite.org/contents/news-releases/2023/news-2023-001

    http://www.nasa.gov/hubble

     

     

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  • NASA’s Webb Uncovers Dense Cosmic Knot in The Early Universe

    NASA’s Webb Uncovers Dense Cosmic Knot in The Early Universe

    Newswise — Astronomers looking into the early universe have made a surprising discovery using NASA’s James Webb Space Telescope: a cluster of massive galaxies in the process of forming around an extremely red quasar. The result will expand our understanding of how galaxy clusters in the early universe came together and formed the cosmic web we see today.

    A quasar, a special type of active galactic nucleus (AGN), is a compact region with a supermassive black hole at the center of a galaxy. Gas falling into a supermassive black hole makes the quasar bright enough to outshine all the galaxy’s stars.

    The quasar Webb explored, called SDSS J165202.64+172852.3, existed 11.5 billion years ago. It is unusually red not just because of its intrinsic red color, but also because the galaxy’s light has been redshifted by its vast distance. That made Webb, having unparalleled sensitivity in infrared wavelengths, perfectly suited to examine the galaxy in detail.

    This quasar is one of the most powerful known galactic nuclei that’s been seen at such an extreme distance. Astronomers had speculated that the quasar’s extreme emission could cause a “galactic wind,” pushing free gas out of its host galaxy and possibly greatly influencing future star formation there.

    To investigate the movement of the gas, dust and stellar material in the galaxy, the team used the telescope’s Near Infrared Spectrograph (NIRSpec). This powerful instrument uses a technique called spectroscopy to look at the movement of various outflows and winds surrounding the quasar. NIRSpec can simultaneously gather spectra across the telescope’s whole field of view, instead of just from one point at a time, enabling Webb to simultaneously examine the quasar, its galaxy and the wider surroundings.

    Previous studies by NASA’s Hubble Space Telescope and other observatories called attention to the quasar’s powerful outflows, and astronomers had speculated that its host galaxy could be merging with some unseen partner. But the team was not expecting Webb’s NIRSpec data to clearly indicate it was not just one galaxy, but at least three more swirling around it. Thanks to spectra over a broad area, the motions of all this surrounding material could be mapped, resulting in the conclusion that the red quasar was in fact part of a dense knot of galaxy formation.

    “There are few galaxy protoclusters known at this early time. It’s hard to find them, and very few have had time to form since the big bang,” said astronomer Dominika Wylezalek of Heidelberg University in Germany, who led the study with Webb. “This may eventually help us understand how galaxies in dense environments evolve. It’s an exciting result.”

    Using the observations from NIRSpec, the team was able to confirm three galactic companions to this quasar and show how they are connected. Archival data from Hubble hint that there may be even more. Images from Hubble’s Wide Field Camera 3 had shown extended material surrounding the quasar and its galaxy, prompting its selection for this study into its outflow and the effects on its host galaxy. Now, the team suspects they could have been looking at the core of a whole cluster of galaxies – only now revealed by Webb’s crisp imaging.

    “Our first look at the data quickly revealed clear signs of major interactions between the neighboring galaxies,” shared team member Andrey Vayner of Johns Hopkins University in Baltimore, Maryland. “The sensitivity of the NIRSpec instrument was immediately apparent, and it was clear to me that we are in a new era of infrared spectroscopy.”

    The three confirmed galaxies are orbiting each other at incredibly high speeds, an indication that a great deal of mass is present. When combined with how closely they are packed into the region around this quasar, the team believes this marks one of the densest known areas of galaxy formation in the early universe. “Even a dense knot of dark matter isn’t sufficient to explain it,” Wylezalek says. “We think we could be seeing a region where two massive halos of dark matter are merging together.” Dark matter is an invisible component of the universe that holds galaxies and galaxy clusters together, and is thought to form a “halo” that extends beyond the stars in these structures.

    The study conducted by Wylezalek’s team is part of Webb’s investigations into the early universe. With its unprecedented ability to look back in time, the telescope is already being used to investigate how the first galaxies were formed and evolved, and how black holes formed and influenced the structure of the universe. The team is planning follow-up observations into this unexpected galaxy proto-cluster, and hope to use it to understand how dense, chaotic galaxy clusters like this one form, and how it’s affected by the active, supermassive black hole at its heart.

    These results will be published in the The Astrophysical Journal Letters. This research was completed as part of Webb’s Early Release Science program #1335.

    The James Webb Space Telescope is the world’s premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

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