#NASA Extends Nancy Grace Roman Space Telescope Science Operations | Explore Tumblr Posts and Blogs

spacetimewithstuartgary · 4 years

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Ground system for NASA's Roman Space Telescope completes major review When it launches in the mid-2020s, NASA's Nancy Grace Roman Space Telescope will create enormous panoramic pictures of space in unprecedented detail. The mission's wide field of view will enable scientists to conduct sweeping cosmic surveys, yielding a wealth of new information about the universe. The Roman mission's ground system, which will make data from the spacecraft available to scientists and the public, has just successfully completed its preliminary design review. The plan for science operations has met all of the design, schedule, and budget requirements, and will now proceed to the next phase: building the newly designed data system. "This is an exciting milestone for the mission," said Ken Carpenter, the Roman ground system project scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "We are on track to complete the data system in time for launch, and we look forward to the ground-breaking science it will enable." Roman will have the same resolution as the Hubble Space Telescope but capture a field of view nearly 100 times larger. Scientists expect the spacecraft to collect more data than any of NASA's other astrophysics missions. Using Hubble's observations, astronomers have revolutionized our view of the universe and unleashed a flood of discoveries. Hubble has gathered 172 terabytes of data since its launch in 1990. If all of this data were printed as text and the pages were placed on top of each other, the stack would reach about 5,000 miles (8,000 kilometers) high. That's far enough to reach about 15 times higher than Hubble's orbit, or about 2% of the distance to the Moon. Roman will gather data about 500 times faster than Hubble, adding up to 20,000 terabytes (20 petabytes) over the course of its five-year primary mission. If this data were printed, the stack of papers would tower 330 miles (530 kilometers) high after a single day. By the end of Roman's primary mission, the stack would extend well beyond the Moon. Untold cosmic treasures will be brought to light by Roman's rich observations. Such a vast volume of information will require NASA to rely on new processing and archival techniques. Scientists will access and analyze Roman's data using cloud-based remote services and more sophisticated tools than those used by previous missions. All of Roman's data will be publicly available within days of the observations - a first for a NASA astrophysics flagship mission. This is significant because Roman's colossal images will often contain far more than the primary target of observation. Since scientists everywhere will have rapid access to the data, they will be able to quickly discover short-lived phenomena, such as supernova explosions. Detecting these phenomena quickly will allow other telescopes to perform follow-up observations. Pinpointing planets One of the science areas that will benefit from the mission's vast data is the microlensing survey. Gravitational lensing is an observational effect that occurs because the presence of mass warps the fabric of space-time. The effect is extreme around very massive objects, like black holes and entire galaxies. But even relatively small objects like stars and planets cause a detectable degree of warping, called microlensing. Any time two stars align closely from our vantage point, light from the more distant star curves as it travels through the warped space-time around the nearer star. The nearer star acts like a natural cosmic lens, focusing and intensifying light from the background star. Scientists see this as a spike in brightness. Planets orbiting the foreground star may also modify the lensed light, acting as their own tiny lenses. These small signatures drive the design of Roman's microlensing survey. "With such a large number of stars and frequent observations, Roman's microlensing survey will see thousands of planetary events," said Rachel Akeson, task lead for the Roman Science Support Center at IPAC/Caltech in Pasadena, California. "Each one will have a unique signature which we can use to determine the planet's mass and distance from its star." Roman's microlensing survey will also detect hundreds of other bizarre and interesting cosmic objects. Roman will discover starless planets that roam the galaxy as rogue worlds; brown dwarfs, which are too massive to be characterized as planets but not massive enough to ignite as stars; and stellar corpses, including neutron stars and black holes, which are left behind when stars exhaust their fuel. Microlensing events are extremely rare and require extensive observations. Roman will monitor hundreds of millions of stars every 15 minutes for months at a time - something no other space telescope can do, generating an unprecedented stream of new information. Gazing beyond our galaxy While the microlensing survey will look toward the heart of our galaxy, where stars are most densely concentrated, Roman's cosmological surveys will peer far beyond our stars to study hundreds of millions of other galaxies. These observations will help illuminate two of the biggest cosmic puzzles: dark matter and dark energy. Visible matter accounts for only about five percent of the contents of the universe. Nearly 27 percent of the universe comes in the form of dark matter, which doesn't emit or absorb light. Dark matter is only detectable through its gravitational effects on visible matter. Roman will help us figure out what dark matter is made of by exploring the structure and distribution of regular matter and dark matter across space and time. This investigation can only be done effectively using precise measurements from many galaxies. The remaining approximately 68 percent of the universe is made up of dark energy. This mysterious cosmic pressure is causing the expansion of the universe to accelerate, but so far we don't know much more about it. Roman will study dark energy through multiple observational strategies, including surveys of galaxy clusters and supernovae. Scientists will create a 3D map of the universe to help us understand how the universe grew over time under the influence of dark energy. Since Roman will have such a large field of view, it will dramatically reduce the amount of time needed to gather data. The Cosmic Assembly Near-infrared Deep Extragalactic Survey (CANDELS) is one of the largest projects ever done with Hubble, designed to study the development of galaxies over time. While it took Hubble nearly 21 days, Roman would complete a similar survey in less than half an hour - 1,000 times faster than Hubble. Using Roman, scientists will be able to extend these observations in ways that would be impractical with other telescopes. "With its incredibly fast survey speeds, Roman will observe planets by the thousands, galaxies by the millions, and stars by the billions," said Karoline Gilbert, mission scientist for the Roman Science Operations Center at the Space Telescope Science Institute in Baltimore. "These vast datasets will allow us to address cosmic mysteries that hint at new fundamental physics." TOP IMAGE....High-resolution illustration of the Roman spacecraft against a starry background. CREDIT NASA's Goddard Space Flight Center CENTRE IMAGE....This simulated image illustrates the wide range of science enabled by Roman's extremely wide field of view and exquisite resolution. The purple squares, which all contain background imagery simulated using data from Hubble's Cosmic Assembly Near-infrared Deep Extragalactic Survey (CANDELS) program, outline the area Roman can capture in a single observation. An orange square shows the field of view of Hubble's Wide Field Camera 3 for comparison. While the CANDELS program took Hubble nearly 21 days to survey in near-infrared light, Roman's large field of view and higher efficiency would allow it to survey the same area in less than half an hour. Top left: This view illustrates a region of the large nearby spiral galaxy M83. Top right: A hypothetical distant dwarf galaxy appears in this magnified view, demonstrating Roman's ability to detect small, faint galaxies at large distances. Bottom left: This magnified view illustrates how Roman will be able to resolve bright stars even in the dense cores of globular star clusters. Bottom right: A zoom of the CANDELS-based background shows the density of high-redshift galaxies Roman will detect. CREDIT Benjamin Williams, David Weinberg, Anil Seth, Eric Bell, Dave Sand, Dominic Benford, and the WINGS Science Investigation Team LOWER IMAGE....This infographic showcases the difference in data volume between the Nancy Grace Roman and Hubble space telescopes. Each day, Roman will send over 500 times more data back to Earth than Hubble. Credits: NASA’s Goddard Space Flight Center

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shirlleycoyle · 4 years

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Scientists Want to Use Dark Matter ‘Lenses’ to Observe Far Reaches of the Universe

One of the most tantalizing enigmas in science is dark matter, a bizarre substance that accounts for about 85 percent of the universe’s mass. Dark matter is tricky to observe because it does not emit light, but that doesn’t mean that it doesn’t interact with light at all.

In fact, the gravitational fields of dark matter clumps may create an abundance of “efficient lenses” that can magnify light from distant objects, according to a study published on Thursday in Science.

These dark matter lenses, which warp light like cosmic funhouse mirrors, could help astronomers observe remote objects located behind the lenses from our perspective on Earth and test out fundamental theories about the universe.

Scientists led by Massimo Meneghetti, a cosmologist at the Astrophysics and Space Science Observatory of Bologna, set out to estimate how many of these small dark matter lenses might be embedded in galaxy clusters, which are huge structures that can contain thousands of gravitationally-bound galaxies.

“Studying the matter distribution in cluster galaxies is important for several reasons,” said Meneghetti in an email. “First of all, we can test the predictions of the cold-dark-matter model. This is the commonly accepted model of dark matter, as it is able to reproduce very nicely several properties of the universe on large scales (much larger than the scales of galaxies and galaxy clusters).”

“The second important motivation for studying the matter distribution in cluster galaxies is to figure out how complex physical phenomena that take place in dense environments shape galaxy evolution,” he added.

If small dark matter lenses turn out to be abundant in galaxy clusters, it could help astronomers peer into otherwise unobservable corners of the universe. The lensing phenomena occurs when a gravitationally influential object, perhaps a dark matter clump, aligns with a source of background light, such as a distant galaxy. As the light travels through the gravitational field of the object, it can become substantially brighter, as if amplified by a cosmic telescope.

“Often the source is magnified, meaning that we have the chance to see tiny details in the lensed images that we would not be able to detect without gravitational lensing,” said Meneghetti.

However, he noted that the lenses tend to mangle the image of the background sources, which means that scientists have to figure out a way to reverse-engineer the original shapes of objects from the deformed lensed versions.

“If we can build a reliable model of how the matter is distributed in the lens, then we can use the model to correct the shape of the lenses’ sources,” Meneghetti explained. “This is very interesting! Using this effect, we can see what very distant and young galaxies look like.”

To better understand dark matter lenses, Meneghetti and his colleagues compared simulations of galaxy clusters to real observations of 11 clusters captured by the Hubble Space Telescope and the Very Large Telescope in Chile.

Surprisingly, there were about 10 times more lenses in the observations than predicted, suggesting that there are either “systematic issues with simulations or incorrect assumptions about the properties of dark matter,” according to the study.

“Our next step will be to investigate other dark matter candidates by running new simulations,” said Meneghetti. “In addition, we plan to extend our analysis to a larger number of galaxy clusters to enlarge our sample of strong lenses and have more data at our disposal to solve this puzzle.”

Meneghetti and his colleagues eagerly await new data from next-generation observatories, such as the Vera C. Rubin Observatory in Chile, which is on track to begin operations in 2021. The European Space Agency's Euclid space telescope and NASA's Nancy Grace Roman Space Telescope, which are both due to launch in the 2020s, will also be crucial instruments for this purpose.

The new telescopes will “produce images of nearly the whole sky and we will be able to discover thousands of new strong lensing clusters,” Meneghetti said. “These observations will be a gold mine for us!”

Scientists Want to Use Dark Matter ‘Lenses’ to Observe Far Reaches of the Universe syndicated from https://triviaqaweb.wordpress.com/feed/

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spacetimewithstuartgary · 3 years

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NASA’s Roman Mission Will Help Empower a New Era of Cosmological Discovery A team of scientists has forecast the scientific impact of the Nancy Grace Roman Space Telescope’s High Latitude Wide Area Survey on critical questions in cosmology. This observation program will consist of both imaging, which reveals the locations, shapes, sizes, and colors of objects like distant galaxies, and spectroscopy, which involves measuring the intensity of light from those objects at different wavelengths, across the same enormous swath of the universe. Scientists will be able to harness the power of a variety of cross-checking techniques using this rich data set, which promises an unprecedented look into some of cosmology’s most vexing problems. When it begins work in 2027, Roman will yield results that would be impossible to achieve using existing telescopes. Its impact will be further enhanced by teaming up with other new facilities like the Vera C. Rubin Observatory, a novel wide-field telescope now being built on the summit of Cerro Pachón in Chile. Scheduled to begin full operations by 2024, Rubin’s planned 10-year survey extends across Roman’s five-year primary mission. “By predicting Roman’s science return, we hope to help the scientific community develop the best strategy for observing the cosmos,” said Tim Eifler, an assistant professor at the University of Arizona in Tucson. “We eagerly await the images and data the mission will send back to help us better understand some of the biggest mysteries in the universe.” The team’s results are described in two papers led by Eifler and published in the October edition of the Monthly Notices of the Royal Astronomical Society. The study is part of an effort by a broader team of world-leading scientists to prepare to analyze Roman’s cosmological data. “Our study was only possible because of all the expertise, from theorists to observers, that is present in the larger team,” Eifler said. A multitalented observatory The Roman mission owes its multifaceted approach to its combination of imaging and spectroscopy across an enormous field of view, which enables two main cosmological techniques: galaxy clustering and weak gravitational lensing. The first measures the exact positions of hundreds of millions of faint galaxies. Weak lensing measures how the images of galaxies have been distorted by the gravity of intervening matter. With its wide, deep view, Roman will allow scientists to study the structure and evolution of the universe and to explore the concept of cosmic acceleration as never before. Learning about how the universe evolved to its present state will offer clues about what’s speeding up the universe’s expansion. In addition to weak lensing and galaxy clustering, Roman will study this mystery in several ways, including surveying the sky for a special type of exploding star called a type Ia supernova. The mission will also probe cosmic acceleration by measuring the masses and redshifts of galaxy clusters, the largest structures in the universe. The number and size of these structures depend on how the speed of the universe’s expansion changes. “Using several different methods to study the cause behind cosmic acceleration will help astronomers greatly reduce the uncertainty that has plagued expansion measurements,” said Hironao Miyatake, an associate professor at Nagoya University in Japan and a co-author of the papers. “Each method will cross-check the others, which is one reason Roman will be able to provide extremely precise results.” Combining so many observational methods will allow astronomers to investigate additional mysteries, too, including determining the amount of dark matter – invisible matter that is detectable only through its gravitational effects – and tracking the growth of black holes in the early universe that form the seeds of massive galaxies. “Roman is designed specifically to solve mysteries such as cosmic acceleration, but its enormous view of the universe will reveal a treasure trove of data that could help explain other puzzles as well,” said Elisabeth Krause, an assistant professor at the University of Arizona and a co-author of the papers. “The mission could even help answer questions no one has thought to ask yet.” Teaming up with Rubin Roman isn’t the only observatory designed to probe cosmic acceleration. In one paper, the team explored how Roman will work hand-in-hand with another telescope: the Rubin Observatory. Named for American astronomer Vera Rubin, who showed that galaxies are mostly made of dark matter, the Rubin Observatory will use its 8.4-meter (27.4-foot) primary mirror to conduct a truly gigantic survey of the sky, covering about 44% of the sky over 10 years. “Roman’s observations will begin, in terms of wavelength, where Rubin’s observations end,” Eifler said. “Roman plans to view a smaller area of the sky, but it will see much deeper and generate clearer pictures since it will be located above Earth’s atmosphere.” The current observing strategy for Roman’s High Latitude Wide Area Survey will enable observations of about 5% of the sky – 2,000 square degrees – over the course of about a year. However, the team illustrated how changing the survey’s design could yield compelling results. The survey could be extended, for example, to cover more of the same area that Rubin will observe. Or it could observe galaxies using a single broad filter, instead of imaging with four separate ones, allowing faster observations while still retaining the survey’s depth. “It is exciting to consider the benefits we would gain from merging the two telescopes’ observations,” Krause said. “Roman will gain from Rubin’s larger observing field, and Rubin will gain enormously from having some deeper observations with Roman’s better image quality. The missions will greatly enhance each other.” The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA's Jet Propulsion Laboratory and Caltech/IPAC in Southern California, the Space Telescope Science Institute in Baltimore, and a science team comprising scientists from various research institutions. The primary industrial partners are Ball Aerospace and Technologies Corporation in Boulder, Colorado; L3Harris Technologies in Melbourne, Florida; and Teledyne Scientific & Imaging in Thousand Oaks, California. IMAGE....This illustration compares the relative sizes of the areas of sky covered by two surveys: Roman’s High Latitude Wide Area Survey, outlined in blue, and the largest mosaic led by Hubble, the Cosmological Evolution Survey (COSMOS), shown in red. In current plans, the Roman survey will be more than 1,000 times broader than Hubble’s. Roman will also explore more distant realms of space than most other telescopes have probed in previous efforts to study why the expansion of the universe is speeding up. Credits: NASA's Goddard Space Flight Center

#space #science #Astronomy #physics #news #nasa

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