It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, April 03, 2024
SPACE
SLAC completes construction of the largest digital camera ever built for astronomy
Once set in place atop a telescope in Chile, the 3,200-megapixel LSST Camera will help researchers better understand dark matter, dark energy and other mysteries of our universe
DOE/SLAC NATIONAL ACCELERATOR LABORATORY
IMAGE:
RESEARCHERS EXAMINE THE LSST CAMERA. THE CAMERA WILL SOON BE SHIPPED TO CHILE, WHERE IT WILL BE THE HEART OF THE VERA C. RUBIN OBSERVATORY (RIGHT).
CREDIT: GREG STEWART/SLAC NATIONAL ACCELERATOR LABORATORY
Menlo Park, Calif. — After two decades of work, scientists and engineers at the Department of Energy's SLAC National Accelerator Laboratory and their collaborators are celebrating the completion of the Legacy Survey of Space and Time (LSST) Camera.
As the heart of the DOE- and National Science Foundation-funded Vera C. Rubin Observatory, the 3,200-megapixel camera will help researchers observe our universe in unprecedented detail. Over ten years, it will generate an enormous trove of data on the southern night sky that researchers will mine for new insights into the universe. That data will aid in the quest to understand dark energy, which is driving the accelerating expansion of the universe, and the hunt for dark matter, the mysterious substance that makes up around 85% of the matter in the universe. Researchers also have plans to use Rubin data to better understand the changing night sky, the Milky Way galaxy, and our own solar system.
“With the completion of the unique LSST Camera at SLAC and its imminent integration with the rest of Rubin Observatory systems in Chile, we will soon start producing the greatest movie of all time and the most informative map of the night sky ever assembled,” said Director of Rubin Observatory Construction and University of Washington professor Željko Ivezić.
To achieve that goal, the SLAC team and its partners built the largest digital camera ever constructed for astronomy. The camera is roughly the size of a small car and weighs around 3,000 kilograms (3 metric tons), and its front lens is over five feet across – the largest lens ever made for this purpose. Another three-foot-wide lens had to be specially designed to maintain shape and optical clarity while also sealing the vacuum chamber that houses the camera's enormous focal plane. That focal plane is made up of 201 individual custom-designed CCD sensors, and it is so flat that it varies by no more than a tenth the width of a human hair. The pixels themselves are only 10 microns wide.
Still, the camera's most important feature is its resolution, which is so high it would take hundreds of ultra-high-definition TVs to display just one of its images at full size, said SLAC professor and Rubin Observatory Deputy Director and Camera Program Lead Aaron Roodman. “Its images are so detailed that it could resolve a golf ball from around 15 miles away, while covering a swath of the sky seven times wider than the full moon. These images with billions of stars and galaxies will help unlock the secrets of the universe.”
And those secrets are increasingly important to reveal, said Kathy Turner, program manager for the DOE's Cosmic Frontier Program. "More than ever before, expanding our understanding of fundamental physics requires looking farther out into the universe," Turner said. "With the LSST Camera at its core, Rubin Observatory will delve deeper than ever before into the cosmos and help answer some of the hardest, most important questions in physics today."
Now that the LSST Camera is complete and has been thoroughly tested at SLAC, it will be packed up and shipped to Chile and driven up 8,900-foot-high Cerro Pachón in the Andes, where it will be hoisted atop the Simonyi Survey Telescope later this year.
Once it's up and running, the camera's essential purpose is to map the positions and measure the brightness of a vast number of night-sky objects. From that catalog, researchers can infer a wealth of information. Perhaps most notably, the LSST Camera will look for signs of weak gravitational lensing, in which massive galaxies subtly bend the paths light from background galaxies take to reach us. Weak lensing reveals something about the distribution of mass in the universe and how that's changed over time, which will help cosmologists understand how dark energy is driving the expansion of the universe.
The observatory is the first built for studying weak lensing on this scale, and the project led scientists and engineers to develop a number of new technologies, including new kinds of CCD sensors and some of the largest lenses ever made – and make sure all of those components worked well together, said Martin Nordby, a senior staff engineer at SLAC and the LSST camera project manager.
Scientists also want to study patterns in the distribution of galaxies and how those have changed over time, identifying clusters of dark matter and spotting supernovae, all of which can help further understanding of dark matter and dark energy alike.
Risa Wechsler, a cosmologist who directs the Kavli Institute for Particle Astrophysics and Cosmology at SLAC and Stanford University, said it was an extraordinary moment. "There are so many scientists here at SLAC and around the world who will find something valuable in the data this camera will produce," Wechsler said. "This is an exciting time to be studying cosmology."
What else do you do with a camera that big?
The same images that reveal details of distant galaxies will help researchers study something closer to home: our own Milky Way galaxy. Many of its stars are small and faint, but with the LSST Camera's sensitivity, researchers expect to produce a far more detailed map of our galaxy, yielding insights into its structure and evolution as well as the nature of stars and other objects within it.
Even closer to home, researchers are hoping to create a far more thorough census of the many small objects in our solar system. According to Rubin Observatory estimates, the project may increase the number of known objects by a factor of 10, which could lead to a new understanding of how our solar system formed and perhaps help identify threats from asteroids that get a little too close to the planet.
Finally, Rubin scientists will look at how the night sky is changing – for example, how stars die or how matter falls into supermassive black holes at the centers of galaxies.
A team effort
SLAC Director John Sarrao said the camera is a "tremendous accomplishment" for the lab and its partners. "The LSST Camera and Rubin Observatory will open new windows into our universe, yielding deep insights into some of its greatest mysteries while also revealing wonders closer to home,” Sarrao said. “It’s exciting to see SLAC’s scientific and technical expertise, project leadership and strong global partnerships come together in such an impactful way. We can’t wait to see what’s next.”
Among the partner labs that contributed expertise and technology are Brookhaven National Laboratory, which built the camera's digital sensor array; Lawrence Livermore National Laboratory, which with its industrial partners designed and built lenses for the camera; and the National Institute of Nuclear and Particle Physics at the National Center for Scientific Research (IN2P3/CNRS) in France, which contributed to sensor and electronics design and built the camera's filter exchange system, which will allow the camera to home in on six separate bands of light from the ultraviolet to infrared.
Paul O'Connor, a senior physicist in Brookhaven's Instrumentation Division, said, "The team at Brookhaven Lab, some of whom have been working on the project for more than 20 years, is excited to see the completion of the LSST Camera. Our fast, ultra-sensitive CCD modules, which we developed with multiple collaborators, will contribute to the breakthrough science delivered by the Rubin Observatory over the next decade, and we look forward to collaborating on this flagship astronomical survey.”
A key feature of the camera’s optical assemblies are its three lenses, one of which at 1.57 meters (5.1 feet) in diameter is believed to be the world’s largest high-performance optical lens ever fabricated. “The Lawrence Livermore National Laboratory is extremely proud to have had the opportunity to design and oversee the fabrication of the large lenses and optical filters for the LSST Camera, including the largest lens in the world,” said Vincent Riot, a LLNL engineer and the former LSST Camera project manager. “LLNL was able to leverage its expertise in large optics, built over decades of developing the world’s largest laser systems, and is excited to see this unprecedented instrument completed and ready to make its journey to the Rubin Observatory.”
IN2P3/CNRS camera scientist Pierre Antilogus said, "To make a 3D movie of the universe, the camera had to take an image in about 2 seconds and change filters in less than 90 seconds. This is quite a feat for a camera of this size. And if the size of the LSST Camera's focal plane is unique, the density of the technology inside is even more impressive. By being in charge of the filter exchange system and contributing to the focal plane, our team is delighted to have taken part in this collective adventure to develop such a powerful camera."
Building the camera has also been a rewarding challenge for the SLAC team that built it and led the project, said Travis Lange, the camera's deputy project manager and camera integration manager. "I'm very proud of what we've built," he said. "This has been such a unique project that has exposed me to incredible experiences – who could have imagined that the Secretary of State and Speaker of the House would hold a press conference in front of the camera clean room? That will be a tough act to follow."
After two decades of work, scientists and engineers at the Department of Energy's SLAC National Accelerator Laboratory and their collaborators have completed the Legacy Survey of Space and Time (LSST) Camera. As the heart of the DOE- and National Science Foundation-funded Vera C. Rubin Observatory, the camera will generate an enormous trove of data on the southern night sky that researchers will mine for new insights about dark energy and dark matter, as well as the changing night sky, the Milky Way galaxy, and our own solar system.
SLAC is a vibrant multiprogram laboratory that explores how the universe works at the biggest, smallest and fastest scales and invents powerful tools used by scientists around the globe. With research spanning particle physics, astrophysics and cosmology, materials, chemistry, bio- and energy sciences and scientific computing, we help solve real-world problems and advance the interests of the nation.
Vera C. Rubin Observatory is a federal project jointly funded by the National Science Foundation and the Department of Energy Office of Science, with early construction funding received from private donations through the LSST Discovery Alliance. The NSF-funded LSST (now Rubin Observatory) Project Office for construction was established as an operating center under the management of the Association of Universities for Research in Astronomy (AURA). The DOE-funded effort to build the Rubin Observatory LSST Camera (LSSTCam) is managed by SLAC.
SLAC is operated by Stanford University for the U.S. Department of Energy’s Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.
A front view of the completed LSST Camera, showing the 3,200-megapixel focal plane within.
CREDIT
Jacqueline Ramseyer Orrell/SLAC National Accelerator Laboratory
Built at SLAC National Accelerator Laboratory, the LSST Camera is the largest digital camera ever built for astronomy. The camera is at the heart of the Vera C. Rubin Observatory's 10-year-long Legacy Survey of Space and Time (LSST), which will capture the entire southern sky every 3 nights. Data from the camera will help address some of the most pressing questions in cosmology, such as the nature of dark energy and dark matter, as well as advancing the study of our solar system and the changing night sky.
Rubin Observatory and LSST Camera
The camera will sit atop Rubin Observatory’s Simonyi Survey Telescope high in the Andes of Chile.
An artist's rendering of the LSST Camera showing its major components including lenses, sensor array, and utility trunk.
CREDIT
Chris Smith/SLAC National Accelerator Laboratory
Three-year study of young stars with NASA’s Hubble enters new chapter
NASA/GODDARD SPACE FLIGHT CENTER
IMAGE:
THE ULLYSES PROGRAM STUDIED TWO TYPES OF YOUNG STARS: SUPER-HOT, MASSIVE, BLUE STARS AND COOLER, REDDER, LESS MASSIVE STARS THAN OUR SUN.
THE TOP PANEL IS A HUBBLE SPACE TELESCOPE IMAGE OF A STAR-FORMING REGION CONTAINING MASSIVE, YOUNG, BLUE STARS IN 30 DORADUS, THE TARANTULA NEBULA. LOCATED WITHIN THE LARGE MAGELLANIC CLOUD, THIS IS ONE OF THE REGIONS OBSERVED BY ULLYSES.
THE BOTTOM PANEL SHOWS AN ARTIST'S CONCEPT OF A COOLER, REDDER, YOUNG STAR THAT'S LESS MASSIVE THAN OUR SUN. THIS TYPE OF STAR IS STILL GATHERING MATERIAL FROM ITS SURROUNDING, PLANET-FORMING DISK.
CREDIT: NASA, ESA, STSCI, FRANCESCO PARESCE (INAF-IASF BOLOGNA), ROBERT O'CONNELL (UVA), SOC-WFC3, ESO
In the largest and one of the most ambitious Hubble Space Telescope programs ever executed, a team of scientists and engineers collected information on almost 500 stars over a three-year period. This effort offers new insights into the stars' formation, evolution, and impact on their surroundings.
This comprehensive survey, called ULLYSES (Ultraviolet Legacy Library of Young Stars as Essential Standards), was completed in December 2023, and provides a rich spectroscopic dataset obtained in ultraviolet light that astronomers will be mining for decades to come. Because ultraviolet light can only be observed from space, Hubble is the only active telescope that can accomplish this research.
"I believe the ULLYSES project will be transformative, impacting overall astrophysics – from exoplanets, to the effects of massive stars on galaxy evolution, to understanding the earliest stages of the evolving universe," said Julia Roman-Duval, Implementation Team Lead for ULLYSES at the Space Telescope Science Institute (STScI) in Baltimore, Maryland. "Aside from the specific goals of the program, the stellar data can also be used in fields of astrophysics in ways we can’t yet imagine."
The ULLYSES team studied 220 stars, then combined those observations with information from the Hubble archive on 275 additional stars. The program also included data from some of the world's largest, most powerful ground-based telescopes and X-ray space telescopes. The ULLYSES dataset is made up of stellar spectra, which carry information about each star's temperature, chemical composition, and rotation.
One type of stars studied under ULLYSES is super-hot, massive, blue stars. They are a million times brighter than the Sun and glow fiercely in ultraviolet light that can easily be detected by Hubble. Their spectra include key diagnostics of the speed of their powerful winds. The winds drive galaxy evolution and seed galaxies with the elements needed for life. Those elements are cooked up inside the stars' nuclear fusion ovens and then injected into space as a star dies. ULLYSES targeted blue stars in nearby galaxies that are deficient in elements heavier than helium and hydrogen. This type of galaxy was common in the very early universe. "ULLYSES observations are a stepping stone to understanding those first stars and their winds in the universe, and how they impact the evolution of their young host galaxy," said Roman-Duval.
The other star category in the ULLYSES program is young stars less massive than our Sun. Though cooler and redder than our Sun, in their formative years they unleash a torrent of high-energy radiation, including blasts of ultraviolet light and X-rays. Because they are still growing, they are gathering material from their surrounding planet-forming disks of dust and gas. The Hubble spectra include key diagnostics of the process by which they acquire their mass, including how much energy this process releases into the surrounding planet-forming disk and nearby environment. The blistering ultraviolet light from young stars affects the evolution of these disks as they form planets, as well as the chances of habitability for newborn planets. The target stars are located in nearby star-forming regions in our Milky Way galaxy.
The ULLYSES concept was designed by a committee of experts with the goal of using Hubble to provide a legacy set of stellar observations. "ULLYSES was originally conceived as an observing program utilizing Hubble's sensitive spectrographs. However, the program was tremendously enhanced by community-led coordinated and ancillary observations with other ground- and space-based observatories," said Roman-Duval. "Such broad coverage allows astronomers to investigate the lives of stars in unprecedented detail and paint a more comprehensive picture of the properties of these stars and how they impact their environment."
To that end, STScI hosted a ULLYSES workshop March 11–14 to celebrate the beginning of a new era of research on young stars. The goal was to allow members of the astronomical community to collaborate on the data, so that they could gain momentum in the ongoing analyses, or kickstart new ideas for analysis. The workshop was one important step in exploiting this legacy spectral library to its fullest potential, fulfilling the promise of ULLYSES.
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
METHOD OF RESEARCH
Observational study
First results from BREAD experiment demonstrate a new approach to searching for dark matter
UChicago, Fermilab research uses coaxial “dish” antenna to scan for mysterious particles
UNIVERSITY OF CHICAGO
One of the great mysteries of modern science is dark matter. We know dark matter exists thanks to its effects on other objects in the cosmos, but we have never been able to directly see it. And it’s no minor thing—currently, scientists think it makes up about 85% of all the mass in the universe.
A new experiment by a collaboration led by the University of Chicago and Fermi National Accelerator Laboratory, known as the Broadband Reflector Experiment for Axion Detection or BREAD, has released its first results in the search for dark matter in a study published in Physical Review Letters. Though they did not find dark matter, they narrowed the constraints for where it might be and demonstrated a unique approach that may speed up the search for the mysterious substance, at relatively little space and cost.
“We’re very excited about what we’ve been able to do so far,” said UChicago Assoc. Prof. David Miller, co-leader for the experiment alongside Fermilab’s Andrew Sonnenschein, who originally developed the concept for the experiment. “There are lots of practical advantages to this design, and we’ve already shown the best sensitivity to date in this 11-12 gigahertz frequency.”
“This result is a milestone for our concept, demonstrating for the first time the power of our approach,” said Fermilab postdoctoral scholar and study lead author Stefan Knirck, who spearheaded the construction and operation of the detector. “It is great to do this kind of creative tabletop-scale science, where a small team can do everything from building the experiment to data analysis, but still have a great impact on modern particle physics.”
‘Something is there’
When we look around the universe, we can see that some kind of substance is exerting enough gravity to pull on stars and galaxies and passing light, but no telescope or device has ever directly picked up the source—hence the name ‘dark matter.’
However, because no one has ever seen dark matter, we don’t even know exactly what it might look like or even precisely where to look for it. “We’re very confident that something is there, but there are many, many forms it could take,” said Miller.
Scientists have mapped out several of the most likely options for places and forms to look. Typically, the approach has been to build detectors to very thoroughly search one specific area (in this case, set of frequencies) in order to rule it out.
But a team of scientists explored a different approach. Their design is “broadband,” meaning that it can search a larger set of possibilities, albeit with slightly less precision.
“If you think about it like a radio, the search for dark matter is like tuning the dial to search for one particular radio station, except there are a million frequencies to check through,” said Miller. “Our method is like doing a scan of 100,000 radio stations, rather than a few very thoroughly.”
A proof of concept
The BREAD detector searches for a specific subset of possibilities. It’s built to look for dark matter in the form of what are known as “axions” or “dark photons”— particles with extremely small masses that could be converted into a visible photon under the right circumstances.
Fermilab's Stefan Knirck with components of the BREAD detector.
Thus, BREAD consists of a metal tube containing a curved surface that catches and funnels potential photons to a sensor at one end. The entire thing is small enough to fit your arms around, which is unusual for these types of experiments.
In the full-scale version, BREAD will be settled inside a magnet to generate a strong magnetic field, which ups the chances of converting dark matter particles into photons.
For the proof of principle, however, the team ran the experiment sans magnets. The collaboration ran the prototype device at UChicago for about a month and analyzed the data.
The results are very promising, showing very high sensitivity in the chosen frequency, the scientists said.
Since the results published in Physical Review Letters were accepted, BREAD has been moved inside a repurposed MRI magnet at Argonne National Laboratory and is taking more data. Its eventual home, at Fermi National Accelerator Laboratory, will use an even stronger magnet.
“This is just the first step in a series of exciting experiments we are planning,” said Sonnenschein. “We have many ideas for improving the sensitivity of our axion search.”
“There are still so many open questions in science, and an enormous space for creative new ideas for tackling those questions,” said Miller. “I think this is a really hallmark example of those kind of creative ideas—in this case, impactful, collaborative partnerships between smaller-scale science at universities and larger-scale science at national laboratories.”
The BREAD instrument was built at Fermilab as part of the laboratory’s detector R&D program and then operated at UChicago, where the data for this study were collected. UChicago Ph.D graduate student Gabe Hoshino led the operation of the detector, along with undergraduate students Alex Lapuente and Mira Littmann.
Argonne National Laboratory maintains an important magnet facility that will be used for the next stage of the BREAD physics program. Other institutions, including SLAC National Accelerator Laboratory, Lawrence Livermore National Laboratory, Illinois Institute of Technology, MIT, the Jet Propulsion Laboratory, the University of Washington, Caltech, and the University of Illinois at Urbana-Champaign, are working with UChicago and Fermilab on R&D for future versions of the experiment.
Funding: U.S. Department of Energy Office of Science, University of Chicago Joint Task Force Initiative, Cambridge Junior Research Fellowship, Kavli Institute for Particle Astrophysics and Cosmology Porat Fellowship.
First Results from a Broadband Search for Dark Photon Dark Matter in the 44 to 52 μ eV Range with a Coaxial Dish Antenna
ARTICLE PUBLICATION DATE
28-Mar-2024
Galaxies get more chaotic as they age
An international team led by Australian research centre ASTRO 3D reports that age is the driving force in changing how stars move within galaxies
ARC CENTRE OF EXCELLENCE FOR ALL SKY ASTROPHYSICS IN 3D (ASTRO 3D)
IMAGE:
A COMPARISON OF A YOUNG (TOP) AND OLD (BOTTOM) GALAXY OBSERVED AS PART OF THE SAMI GALAXY SURVEY. PANELS ON THE LEFT ARE REGULAR OPTICAL IMAGES FROM THE SUBARU TELESCOPE. IN THE MIDDLE ARE ROTATIONAL VELOCITY MAPS (BLUE COMING TOWARDS US, RED GOING AWAY FROM US) FROM SAMI. ON THE RIGHT ARE MAPS MEASURING RANDOM VELOCITIES (REDDER COLOURS FOR GREATER RANDOM VELOCITY). BOTH GALAXIES HAVE THE SAME TOTAL MASS. THE TOP GALAXY HAS AN AVERAGE AGE OF 2 BILLION YEARS, HIGH ROTATION AND LOW RANDOM MOTION. THE BOTTOM GALAXY HAS AN AVERAGE AGE OF 12.5 BILLION YEARS, SLOWER ROTATION AND MUCH LARGER RANDOM MOTION.
CREDIT: SUBARU CREDIT: IMAGE FROM THE HYPER SUPRIME-CAM SUBARU STRATEGIC PROGRAM
Galaxies start life with their stars rotating in an orderly pattern but in some the motion of stars in more random. Until now, scientists have been uncertain about what causes this – possibly the surrounding environment or the mass of the galaxy itself.
A new study, published in a paper today in MNRAS (Monthly Notices of the Royal Astronomical Society), has found that the most important factor is neither of these things. It shows the tendency of the stars to have random motion is driven mostly by the age of the galaxy – things just get messy over time.
“When we did the analysis, we found that age, consistently, whichever way we slice or dice it, is always the most important parameter,” says first author Prof Scott Croom, an ASTRO 3D researcher at the University of Sydney.
“Once you account for age, there is essentially no environmental trend, and it’s similar for mass.
“If you find a young galaxy it will be rotating, whatever environment it is in, and if you find an old galaxy, it will have more random orbits, whether it’s in a dense environment or a void.”
The research team also included scientists from Macquarie University, Swinburne University of Technology, the University of Western Australia, the Australian National University, the University of New South Wales, the University of Cambridge, the University of Queensland, and Yonsei University in the Republic of Korea.
The study updates our understanding from previous studies that have variously suggested environment or mass as more important factors. But the earlier work is not necessarily incorrect, says second author Dr Jesse van de Sande.
Young galaxies are star-forming super-factories, while in older ones, star formation ceases.
“We do know that age is affected by environment. If a galaxy falls into a dense environment, it will tend to shut down the star formation. So galaxies in denser environments are, on average, older,” Dr van de Sande says.
“The point of our analysis is that it’s not living in dense environments that reduces their spin, it’s the fact that they’re older.”
Our own galaxy, the Milky Way, still has a thin star forming disk, so is still considered a high spin rotational galaxy.
“But when we look at the Milky Way in detail, we do see something called the Milky Way thick disk. It’s not dominant, in terms of light, but it is there and those look to be older stars, which may well have been heated from the thin disk at earlier times, or born with more turbulent motion in the early Universe,” Prof Croom says.
The research used data from observations made under the SAMI Galaxy Survey. The SAMI instrument was built in 2012 by the University of Sydney and the Anglo-Australian Observatory (now Astralis). SAMI uses the Anglo-Australian Telescope, at Siding Spring Observatory, near Coonabarabran, New South Wales. It has surveyed 3000 galaxies across a large range of environments.
The study allows astronomers to rule out many processes when trying to understand galaxy formation and so fine-tune models of how the Universe has developed.
The next steps will be to develop simulations of galaxy evolution with more granular detail.
“One of the challenges of getting simulations right is the high resolution you need in to predict what's going on. Typical current simulations are based on particles which have the mass of maybe 100,000 stars and you can't resolve small-scale structures in galaxy disks,” Prof. Croom says.
The Hector Galaxy Survey will help Prof Croom and his team expand this work using a new instrument on the Anglo-Australian Telescope.
“Hector is observing 15,000 galaxies but with higher spectral resolution, allowing the age and spin of galaxies to be measured even in much lower mass galaxies and with more detailed environmental information,” says Professor Julia Bryant, lead of the Hector Galaxy Survey, University of Sydney.
Professor Emma Ryan-Weber, Director of ASTRO 3D, says, “These findings answer one of the key questions posed by ASTRO 3D: how does mass and angular momentum evolve in the Universe? This careful work by the SAMI team reveals that the age of a galaxy determines how the stars orbit. This critical piece of information contributes to a clearer big-picture view of the Universe.”
ABOUT ASTRO 3D
The ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) is a $40m Research Centre of Excellence funded by the Australian Research Council (ARC) and nine collaborating Australian universities – The Australian National University, The University of Sydney, The University of Melbourne, Swinburne University of Technology, The University of Western Australia, Curtin University, Macquarie University, The University of New South Wales, and Monash University.
ABOUT the SAMI Galaxy Survey
The SAMI Galaxy Survey began in March 2013, with the intention of creating a large survey of 3000 galaxies across a large range of environment. The data for the SAMI Galaxy Survey was collected using SAMI, the Sydney-Australian-Astronomical-Observatory Multi-object Integral-Field Spectrograph. SAMI is an instrument on the 4-meter Anglo-Australian Telescope at Siding Spring Observatory. Integral-field spectroscopy (IFS) allows a unique view of how stars and gas zoom around inside distant galaxies because we collect dozens of spectra across the entire face of each galaxy.
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