Images released Tuesday by NASA show rare Wolf-Rayet star WR124 in unprecedented detail.
March 14 (UPI) -- NASA's James Webb Telescope captured a rare Wolf-Rayet star, one of the first times an image of that type of supernova has been seen.
The space agency Tuesday released images of the star in transition, which were captured in "unprecedented detail."
Wolf-Rayet 124 comes with "a distinctive halo of gas and dust that frames the star and glows in the infrared light detected by Webb, displaying knotty structure and a history of episodic ejections," NASA said in a statement.
The cosmic dust that is formed as gas is ejected away from the star, cooling along the way.
Referred to by scientists as a "dust budget," dust that survives a supernova explosion is important for astronomers as they attempt to get a better understanding of the celestial objects.
"It shelters forming stars, gathers together to help form planets, and serves as a platform for molecules to form and clump together -- including the building blocks of life on Earth. Despite the many essential roles that dust plays, there is still more dust in the universe than astronomers' current dust-formation theories can explain. The universe is operating with a dust budget surplus."
The cosmic dust is "composed of the heavy-element building blocks of the modern universe, including life on Earth."
Wolf-Rayet stars go through rapid expansion early in their lives.
They are some of the biggest and brightest stars in the sky, often expanding to a mass 20 times bigger than our sun.
Their decline is rapid, losing half their mass by the time they're 100,000 years old, culminating with a massive supernova explosion when they die.
NASA’s Fermi captures dynamic gamma-ray sky in new animation
IMAGE: WATCH A COSMIC GAMMA-RAY FIREWORKS SHOW IN THIS ANIMATION USING JUST A YEAR OF DATA FROM THE LARGE AREA TELESCOPE (LAT) ABOARD NASA’S FERMI GAMMA-RAY SPACE TELESCOPE. EACH OBJECT’S MAGENTA CIRCLE GROWS AS IT BRIGHTENS AND SHRINKS AS IT DIMS. THE YELLOW CIRCLE REPRESENTS THE SUN FOLLOWING ITS APPARENT ANNUAL PATH ACROSS THE SKY. THE ANIMATION SHOWS A SUBSET OF THE LAT GAMMA-RAY RECORDS NOW AVAILABLE FOR MORE THAN 1,500 OBJECTS IN A NEW, CONTINUALLY UPDATED REPOSITORY. OVER 90% OF THESE SOURCES ARE A TYPE OF GALAXY CALLED A BLAZAR, POWERED BY THE ACTIVITY OF A SUPERMASSIVE BLACK HOLE. view more
CREDIT: NASA'S MARSHALL SPACE FLIGHT CENTER/DANIEL KOCEVSKI
Cosmic fireworks, invisible to our eyes, fill the night sky. We can get a glimpse of this elusive light show thanks to the Large Area Telescope (LAT) aboard NASA’s Fermi Gamma-ray Space Telescope, which observes the sky in gamma rays, the highest-energy form of light.
This animation shows the gamma-ray sky’s frenzied activity during a year of observations from February 2022 to February 2023. The pulsing circles represent just a subset of more than 1,500 light curves – records of how sources change in brightness over time – collected by the LAT over nearly 15 years in space.
Thanks to the work of an international team of astronomers, this data is now publicly available in a continually updated interactive library. A paper about the repository was published March 15, 2023, in The Astrophysical Journal Supplement Series.
“We were inspired to put this database together by astronomers who study galaxies and wanted to compare visible and gamma-ray light curves over long time scales,” said Daniel Kocevski, a repository co-author and an astrophysicist at NASA’s Marshall Space Flight Center in Huntsville, Alabama. “We were getting requests to process one object at a time. Now the scientific community has access to all the analyzed data for the whole catalog.”
Over 90% of the sources in the dataset are blazars, central regions of galaxies hosting active supermassive black holes that produce powerful particle jets pointed almost directly at Earth. Ground-based observatories, like the National Science Foundation’s IceCube Neutrino Observatory in Antarctica, can sometimes detect high-energy particles produced in these jets. Blazars are important sources for multimessenger astronomy, where scientists use combinations of light, particles, and space-time ripples to study the cosmos.
“In 2018, astronomers announced a candidate joint detection of gamma rays and a high-energy particle called a neutrino from a blazar for the first time, thanks to Fermi LAT and IceCube,” said co-author Michela Negro, an astrophysicist at the University of Maryland, Baltimore County, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Having the historical light curve database could lead to new multimessenger insights into past events.”
In the animation, each frame represents three days of observations. Each object's magenta circle grows as it brightens and shrinks as it dims. Some objects fluctuate throughout the entire year. The reddish orange band running across the middle of the sky is the central plane of our Milky Way galaxy, a consistent gamma-ray producer. Lighter colors there indicate a brighter glow. The yellow circle shows the Sun’s apparent annual trajectory across the sky.
Processing the full catalog required about three months, or more than 400 computer years of processing time distributed over 1,000 nodes on a computer cluster located at the SLAC National Accelerator Laboratory in Menlo Park, California.
The LAT, Fermi’s primary instrument, scans the entire sky every three hours. It detects gamma rays with energies ranging from 20 million to over 300 billion electron volts. For comparison, the energy of visible light mostly falls between 2 to 3 electron volts.
The Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership managed by Goddard. Fermi was developed in collaboration with the U.S. Department of Energy, with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States.
JOURNAL
The Astrophysical Journal
ARTICLE TITLE
The Fermi-LAT Lightcurve Repository
ARTICLE PUBLICATION DATE
15-Mar-2023
Largest catalog of exploding stars now available
Celestial phenomena that change with time such as exploding stars, mysterious objects that suddenly brighten and variable stars are a new frontier in astronomical research, with telescopes that can rapidly survey the sky revealing thousands of these objects.
The largest data release of relatively nearby supernovae (colossal explosions of stars), containing three years of data from the University of Hawaiʻi Institute for Astronomy’s (IfA) Pan-STARRS telescope atop Haleakalā on Maui, is publicly available via the Young Supernova Experiment (YSE). The project, which began in 2019, surveyed more than 1,500 square degrees of sky every three days, and discovered thousands of new cosmic explosions and other astrophysical transients, dozens of them just days or hours after exploding.
The newly-released data contains information on nearly 2,000 supernovae and other luminous variable objects with observations in multiple colors. It is also the first to extensively use the multi-color imaging to classify the supernovae and estimate their distances.
Astrophysicists use large imaging surveys—systematic studies of large areas of the sky over time—and different parts of the electromagnetic spectrum for many scientific goals. Some are used to study distant galaxies and how they evolve over cosmic time, or look at specific regions of the sky that are especially important, such as the Andromeda Galaxy.
"Pan-STARRS produces a steady stream of transient discoveries, observing large areas of the sky every clear night with two telescopes,” said Mark Huber, a senior researcher at IfA. “With over a decade of observations, Pan-STARRS operates one of the best calibrated systems in astronomy, with a detailed reference image of the static sky visible from Haleakalā. This enables rapid discovery and follow-up of supernovae and other transient events, well suited for programs like YSE to build up the sample required for analysis and this significant data release."
YSE is designed to find energetic astrophysical “transient” sources such as supernovae, tidal disruption events and kilonovae (extremely energetic explosions). These transients evolve quickly, rising to their maximum brightness and then fading away after a few days or months.
Multi-institution collaboration
The images from Pan-STARRS are transferred to UH’s Information Technology Center for initial processing and scientific calibration by the Pan-STARRS Image Processing Pipeline. Higher-level processing, detailed analysis and storage was then performed using computing systems at the National Center for Supercomputing Applications’ (NCSA) Center for Astrophysical Surveys (CAPS), the University of California, Santa Cruz (UCSC), and the Dark Cosmology Centre (DARK) at the Niels Bohr Institute at the University of Copenhagen.
The survey and the tools used to analyze the data are critical precursors to the upcoming Vera C. Rubin Observatory Legacy Survey of Space and Time, a new 8.4-meter telescope being built in Chile. Rubin Observatory will survey the entire sky every three nights, discovering so many variable and exploding objects that it will be impossible to obtain detailed follow-up observations. The ability to classify these objects from the survey data alone will be vital to choosing the most interesting ones for astronomers to target with other telescopes.
Gautham Narayan, deputy director of CAPS, is leading the cosmological analysis for the data sample and former CAPS graduate fellow Patrick Aleo is lead author of the paper, “The Young Supernova Experiment Data Release 1 (YSE DR1): Light Curves and Photometric Classification of 1975 Supernovae.”
“Much of the time-domain universe is uncharted. We still do not know the progenitor systems of many of the most common classes of transients, such as type Ia supernovae, while still using these sources to try and understand the expansion history of our universe,” Narayan said. “We’ve also seen one electromagnetic counterpart to a binary neutron star merger. There are many kinds of transients that are theoretically predicted, but have never been seen at all.”
Ken Chambers, Pan-STARRS director, added that “this collaboration with the Young Supernova Experiment makes exceptional use of Pan-STARRS’ ability to routinely survey the sky for transient phenomena and moving objects. We have provided an unprecedented sample of young supernovae discovered before their peak luminosity that will be an important resource for supernova researchers and cosmologists for many years. Looking ahead, Pan-STARRS will remain a crucial resource in the Northern Hemisphere to complement the Rubin Observatory in the Southern Hemisphere.”
This groundbreaking effort is a collaboration between UH, UCSC, DARK, NCSA and University of Illinois - Urbana-Champaign (UIUC) and the University of Hawaiʻi. The collaboration used Hawaiʻi’s Pan-STARRS1 telescope and data pipeline to collect and process the images, DARK’s analysis of the data on its computing cluster, UCSC’s organization of the survey and data hosting, and NCSA and UIUC’s analysis.
JOURNAL
The Astrophysical Journal Supplement Series
METHOD OF RESEARCH
Meta-analysis
ARTICLE TITLE
The Young Supernova Experiment Data Release 1 (YSE DR1): Light Curves and Photometric
ARTICLE PUBLICATION DATE
15-Mar-2023
COI STATEMENT
https://arxiv.org/pdf/2211.07128.pdf
Researchers uncover the first bubble in an intergalactic stew
IMAGE: FIGURE 1. THIS FIGURE COMPARES OBSERVED HYDROGEN ABSORPTION IN VICINITY OF THE COSTCO-I GALAXY PROTOCLUSTER (TOP PANEL), COMPARED WITH THE EXPECTED ABSORPTION GIVEN THE PRESENCE OF THE PROTOCLUSTER AS COMPUTED FROM COMPUTER SIMULATIONS. STRONG HYDROGEN ABSORPTION IS SHOWN IN RED, LOWER WHILE WEAK ABSORPTION IS SHOWN IN BLUE, AND INTERMEDIATE ABSORPTION IS DENOTED AS GREEN OR YELLOW COLORS. THE BLACK DOTS IN THE FIGURE SHOW WHERE ASTRONOMERS HAVE DETECTED GALAXIES IN THAT AREA. AT THE POSITION OF COSTCO-I (WITH ITS CENTER MARKED AS A STAR IN BOTH PANELS), ASTRONOMERS FOUND THAT THE OBSERVED HYDROGEN ABSORPTION IS NOT OF MUCH DIFFERENT FROM THE MEAN VALUE OF THE UNIVERSE AT THAT EPOCH. THIS IS SURPRISING BECAUSE ONE WOULD EXPECT TO FIND EXTENDED HYDROGEN ABSORPTION SPANNING MILLIONS OF LIGHT YEARS IN THAT REGION CORRESPONDING TO THE HIGH OBSERVED CONCENTRATION OF GALAXIES. view more
CREDIT: DONG ET AL.
An international team led by researchers at the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) have found the earliest evidence of parts of the universe that were heated to temperatures more characteristic to the intergalactic gas medium where most atoms reside in the universe today, reports a new study in The Astrophysical Journal Letters.
Approximately 90 of all atoms in the universe reside in the intergalactic gas that fills the vast expanses of space outside of visible galaxies. Today, this intergalactic medium exists in a hot, complex state with temperatures ranging from 100,000 degrees Celsius to more than 10 million degrees Celsius, which researchers often call the ‘Warm-Hot Intergalactic Medium’ (WHIM).
However, more than 10 billion years ago, a time when galaxies in the universe were at the peak of forming their stars, most of the intergalactic medium existed at comparatively cooler temperatures of less than 10,000 degrees Celsius, creating a more predictable and stable phase.
An international team of researchers led by Kavli IPMU graduate student Chenze Dong and Project Assistant Professor Khee-Gan Lee, have identified the furthest patch of the universe heated up to temperatures more characteristic of the today’s WHIM at a time when the universe was only 3 billion years old. This region is a giant aggregation of galaxies known as ‘COSTCO-I’, a galaxy protocluster with a total mass of over 400 trillion times the mass of the Sun, and spanning several million light years across, which was also discovered by the Lee and a team of researchers at Kavli IPMU in 2022.
Although galaxy protoclusters in the distant universe such as this are regularly discovered, the team found something strange when they checked ultra-violet spectra covering COSTCO-I using the 10.3-meter diameter Keck-I Telescope at the W.M. Keck Observatory on Maunakea, Hawai’i.
Usually, the large mass and size of galaxy protoclusters would cast a large shadow when viewed at the specific wavelength of 121.6 nanometers, caused by the absorption by the neutral hydrogen associated with the protocluster gas.
But no absorption shadow was found at the location of COSTCO-I.
“We were surprised at the absence because hydrogen absorption is one of the common ways to search for galaxy protoclusters, and other protoclusters near COSTCO-I do show this absorption signal”, said Dong.
The absence of neutral hydrogen tracing the protocluster indicates the gas in the protocluster must be heated to possibly a million-degrees above the cool state expected for the intergalactic medium at that time in the universe.
“If we think about the present-day intergalactic medium as a gigantic cosmic stew that is boiling and frothing, then COSTCO-I is probably the first bubble in the distant past that astronomers have observed during an era while most of the pot was still cold”, said Lee.
“The properties and origin of the WHIM remains one of the biggest questions in astrophysics right now, and to be able to glimpse at one of the early heating sites of the WHIM will help reveal the mechanisms that caused the intergalactic gas to boil up into the present-day froth. There are a few possibilities for how this can happen, but it might be either from gas heating up as they collide with each other during gravitational collapse, or giant radio jets might be pumping energy from supermassive black holes within the protocluster,” he said.
“The COSTCO-I is even interesting in terms of protocluster evolution. Astronomers normally look for protoclusters in galaxies or the intergalactic medium to find them. COSTCO-I, however, cannot be found by those traditional methods. The future PFS survey will be able to search for more such protoclusters, like COSTCO-I, and reveal their evolution,” said co-author and JSPS Overseas Research Fellow Rieko Momose.
The intergalactic medium represents the gas reservoir feeding raw material to galaxies, and hot gas behaves differently from cold gas in how easily they can stream into galaxies to form stars. Being able to directly study the growth of the WHIM in the early universe would allow astronomers to build up a coherent picture of galaxy formation and the lifecycle of gas that feeds it.
Kavli IPMU astronomers are currently heavily involved in the development of a powerful new multi-object spectrograph for the 8.2m Subaru Telescope on Maunakea, known as the Subaru Prime Focus Spectrograph (PFS). With Subaru PFS, astronomers will be able to map out 40 times larger volumes that in the current study and study the gas properties in hundreds of galaxy protoclusters.
Details of the study were published on March 14 in The Astrophysical Journal Letters.
Figure 2. A simulated visualization depicts the scenario of large-scale heating around a galaxy protocluster, using data from supercomputer simulations. This is believed to be a similar scenario to that observed in the COSTCO-I protocluster. The yellow area in the center of the picture represents a huge, hot gas blob spanning several million light years. The blue color indicates cooler gas, which located in the outer regions of the protocluster and the filaments connecting the hot gas with other structures. The white points in the image, which is embedded within gas distribution, is the light emitted from stars.
CREDIT
The THREE HUNDRED Collaboration
JOURNAL
The Astrophysical Journal Letters
ARTICLE TITLE
Observational Evidence for Large-Scale Gas Heating in a Galaxy Protocluster at z = 2.3
ARTICLE PUBLICATION DATE
14-Mar-2023
Are we alone? University engages
satellite company in search for life
among the stars
Alpha Centauri is tantalisingly close to search for extra-terrestrial life
Business AnnouncementIMAGE: PROFESSOR PETER TUTHILL FROM THE SCHOOL OF PHYSICS AT THE UNIVERSITY OF SYDNEY view more
CREDIT: UNIVERSITY OF SYDNEY/ENDUROSAT
The University of Sydney has signed a contract with EnduroSat, a leading provider of micro satellites and space services, to explore the question of life beyond Earth, starting with our nearest neighbour star system, Alpha Centauri.
Backed by the Breakthrough Initiatives in California, the mission was dubbed TOLIMAN after the star’s ancient Arabic name. It will search for planets in the habitable or “Goldilocks” zone around two Sun-like stars in the system, Alpha Centauri A and B, which are just four light years from Earth.
Mission leader Professor Peter Tuthill from the University of Sydney said: “That’s tantalisingly close to home. Astronomers have discovered thousands of exoplanets outside our own solar system but most are thousands of light years away and beyond our reach.
“Modern satellite technology will allow us to explore our celestial backyard and perhaps lay the groundwork for visionary future missions spanning the interstellar voids to the Centauri system.”
Discovering exoplanets is a major technological challenge, even for large space telescopes. For a mini satellite, the task is daunting. To achieve this, the team is developing a small custom-designed space telescope capable of extremely fine measurements.
The satellite needs to fit the telescope within a limited volume – just 12 litres – and maintain its thermal and mechanical stability with exquisite precision using active systems. EnduroSat will provide the delivery system for the custom-built mini satellite that supports the mission.
“Any exoplanets we find that close to Earth can be followed up with other instruments, giving excellent prospects for discovering and analysing atmospheres, surface chemistry or even fingerprints of a biosphere – the tentative signs of life,” said Professor Tuthill from the Sydney Institute for Astronomy and School of Physics.
EnduroSat’s flight-proven MicroSat technology can downlink payload data at a speed of 125+ Mbps, which will be critical for downloading all data from prolonged observation sessions.
Founder and CEO of EnduroSat, Raycho Raychev, said: “We are exceptionally proud to partner in this mission. The challenges are enormous, and it will drive our engineering efforts to the extreme. The mission is a first-of-its-kind exploration science effort and will help open the doors for low-cost astronomy missions.”
Dr S. Pete Worden, Executive Director of Breakthrough Initiatives, said: “It’s very exciting to see this program come to life. With these partnerships, we can create a new kind of astronomical mission and make real progress on understanding the planetary systems right next door.”
Professor Tuthill has a proven track record in designing high-precision instrumentation and projects for international astronomy projects. He is the only Australian scientist to have led direct instrument design work on NASA’s James Webb Space Telescope project, which has heralded a new era in observational astronomy.
He worked on designing the NIRISS Aperture Masking Interferometry mode on the James Webb. This offers high spatial observational resolution, critical in the hunt for exoplanets.
Professor Tuthill said: “My experience helping to develop technology for James Webb will be hugely useful in designing observational equipment for the TOLIMAN project.”
Simulation of the Centauri binary star system as potentially viewed by the Toliman mission.
Optical and X-ray imagery of Alpha Centauri, just four light years away.
CREDIT
NASA
Photo of Alpha Centauri A and B taken by the Hubble Space Telescope.
CREDIT
ESA-NASA/Hubble
TOLIMAN mission logo
CREDIT
Breakthrough Initiatives
Professor Peter Tuthill from the University of Sydney is the TOLIMAN mission leader.
CREDIT
The University of Sydney
Background information
Worlds Next Door: the search for habitable planets around Alpha Centauri (November 2021)
ABC TV: James Webb Telescope, including interview with Professor Tuthill (December 2021)
About EnduroSat
EnduroSat provides unique space data service, based on its software-defined NanoSats, to business, exploration and science teams. Its focus is on the development of next-generation commercial space services and exploration programs. EnduroSat’s team exceeds 120+ talented developers, engineers and scientists, serving more than 210 clients worldwide.
Media contact EnduroSat:
Delyan Momchilov
Marketing & Comms Lead
About Breakthrough Initiatives
The Breakthrough Initiatives are a suite of scientific and technological programs investigating the fundamental questions of life in the Universe. The Breakthrough Initiatives are funded by the Breakthrough Foundation established by Julia and Yuri Milner. Additional information about Yuri Milner: yurimilner.com.
DECLARATION
The project has received seed funding from the Breakthrough Initiatives and funding from the Australian Government’s International Space Investment Expand Capability Grants program.
