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    • By NASA
      Illustration of the main asteroid belt, orbiting the Sun between Mars and JupiterNASA NASA’s powerful James Webb Space Telescope includes asteroids on its list of objects studied and secrets revealed. 
      A team led by researchers at the Massachusetts Institute of Technology (MIT) in Cambridge repurposed Webb’s observations of a distant star to reveal a population of small asteroids — smaller than astronomers had ever detected orbiting the Sun in the main asteroid belt between Mars and Jupiter.
      The 138 new asteroids range from the size of a bus to the size of a stadium — a size range in the main belt that has not been observable with ground-based telescopes. Knowing how many main belt asteroids are in different size ranges can tell us something about how asteroids have been changed over time by collisions. That process is related to how some of them have escaped the main belt over the solar system’s history, and even how meteorites end up on Earth.  
      “We now understand more about how small objects in the asteroid belt are formed and how many there could be,” said Tom Greene, an astrophysicist at NASA’s Ames Research Center in California’s Silicon Valley and co-author on the paper presenting the results. “Asteroids this size likely formed from collisions between larger ones in the main belt and are likely to drift towards the vicinity of Earth and the Sun.”
      Insights from this research could inform the work of the Asteroid Threat Assessment Project at Ames. ATAP works across disciplines to support NASA’s Planetary Defense Coordination Office by studying what would happen in the case of an Earth impact and modeling the associated risks. 
      “It’s exciting that Webb’s capabilities can be used to glean insights into asteroids,” said Jessie Dotson, an astrophysicist at Ames and member of ATAP. “Understanding the sizes, numbers, and evolutionary history of smaller main belt asteroids provides important background about the near-Earth asteroids we study for planetary defense.”
      Illustration of the James Webb Space TelescopeNASA The team that made the asteroid detections, led by research scientist Artem Burdanov and professor of planetary science Julien de Wit, both of MIT, developed a method to analyze existing Webb images for the presence of asteroids that may have been inadvertently “caught on film” as they passed in front of the telescope. Using the new image processing technique, they studied more than 10,000 images of the star TRAPPIST-1, originally taken to search for atmospheres around planets orbiting the star, in the search for life beyond Earth. 
      Asteroids shine more brightly in infrared light, the wavelength Webb is tuned to detect, than in visible light, helping reveal the population of main belt asteroids that had gone unnoticed until now. NASA will also take advantage of that infrared glow with an upcoming mission, the Near-Earth Object (NEO) Surveyor. NEO Surveyor is the first space telescope specifically designed to hunt for near-Earth asteroids and comets that may be potential hazards to Earth.
      The paper presenting this research, “Detections of decameter main-belt asteroids with JWST,” was published Dec. 9 in Nature.
      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 CSA (Canadian Space Agency).
      For news media:
      Members of the news media interested in covering this topic should reach out to the NASA Ames newsroom.
      View the full article
    • By NASA
      NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA Known as flow formations, these channels could be etched on bodies that would seem inhospitable to liquid because they are exposed to the extreme vacuum conditions of space.
      Pocked with craters, the surfaces of many celestial bodies in our solar system provide clear evidence of a 4.6-billion-year battering by meteoroids and other space debris. But on some worlds, including the giant asteroid Vesta that NASA’s Dawn mission explored, the surfaces also contain deep channels, or gullies, whose origins are not fully understood.
      A prime hypothesis holds that they formed from dry debris flows driven by geophysical processes, such as meteoroid impacts, and changes in temperature due to Sun exposure. A recent NASA-funded study, however, provides some evidence that impacts on Vesta may have triggered a less-obvious geologic process: sudden and brief flows of water that carved gullies and deposited fans of sediment. By using lab equipment to mimic conditions on Vesta, the study, which appeared in Planetary Science Journal, detailed for the first time what the liquid could be made of and how long it would flow before freezing.
      Although the existence of frozen brine deposits on Vesta is unconfirmed, scientists have previously hypothesized that meteoroid impacts could have exposed and melted ice that lay under the surface of worlds like Vesta. In that scenario, flows resulting from this process could have etched gullies and other surface features that resemble those on Earth.
      To explore potential explanations for deep channels, or gullies, seen on Vesta, scientists used JPL’s Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE, to simulate conditions on the giant asteroid that would occur after meteoroids strike the surface.NASA/JPL-Caltech But how could airless worlds — celestial bodies without atmospheres and exposed to the intense vacuum of space — host liquids on the surface long enough for them to flow? Such a process would run contrary to the understanding that liquids quickly destabilize in a vacuum, changing to a gas when the pressure drops.
      “Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said project leader and planetary scientist Jennifer Scully of NASA’s Jet Propulsion Laboratory in Southern California, where the experiments were conducted. “But for how long? Most liquids become unstable quickly on these airless bodies, where the vacuum of space is unyielding.”
      The critical component turns out to be sodium chloride — table salt. The experiments found that in conditions like those on Vesta, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour. “That’s long enough to form the flow-associated features identified on Vesta, which were estimated to require up to a half-hour,” said lead author Michael J. Poston of the Southwest Research Institute in San Antonio.
      Launched in 2007, the Dawn spacecraft traveled to the main asteroid belt between Mars and Jupiter to orbit Vesta for 14 months and Ceres for almost four years. Before ending in 2018, the mission uncovered evidence that Ceres had been home to a subsurface reservoir of brine and may still be transferring brines from its interior to the surface. The recent research offers insights into processes on Ceres but focuses on Vesta, where ice and salts may produce briny liquid when heated by an impact, scientists said.
      Re-creating Vesta
      To re-create Vesta-like conditions that would occur after a meteoroid impact, the scientists relied on a test chamber at JPL called the Dirty Under-vacuum Simulation Testbed for Icy Environments, or DUSTIE. By rapidly reducing the air pressure surrounding samples of liquid, they mimicked the environment around fluid that comes to the surface. Exposed to vacuum conditions, pure water froze instantly. But salty fluids hung around longer, continuing to flow before freezing.
      The brines they experimented with were a little over an inch (a few centimeters) deep; scientists concluded the flows on Vesta that are yards to tens of yards deep would take even longer to refreeze.
      The researchers were also able to re-create the “lids” of frozen material thought to form on brines. Essentially a frozen top layer, the lids stabilize the liquid beneath them, protecting it from being exposed to the vacuum of space — or, in this case the vacuum of the DUSTIE chamber — and helping the liquid flow longer before freezing again.
      This phenomenon is similar to how on Earth lava flows farther in lava tubes than when exposed to cool surface temperatures. It also matches up with modeling research conducted around potential mud volcanoes on Mars and volcanoes that may have spewed icy material from volcanoes on Jupiter’s moon Europa.
      “Our results contribute to a growing body of work that uses lab experiments to understand how long liquids last on a variety of worlds,” Scully said.
      Find more information about NASA’s Dawn mission here:
      https://science.nasa.gov/mission/dawn/
      News Media Contacts
      Gretchen McCartney
      Jet Propulsion Laboratory, Pasadena, Calif.
      818-287-4115
      gretchen.p.mccartney@jpl.nasa.gov 
      Karen Fox / Molly Wasser
      NASA Headquarters, Washington
      202-358-1600
      karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
      2024-178
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      Last Updated Dec 20, 2024 Related Terms
      Dawn Asteroids Ceres Jet Propulsion Laboratory Vesta Explore More
      5 min read Avalanches, Icy Explosions, and Dunes: NASA Is Tracking New Year on Mars
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    • By European Space Agency
      Image: Hera asteroid mission in your house View the full article
    • By NASA
      5 Min Read NASA DAVINCI Mission’s Many ‘Firsts’ to Unlock Venus’ Hidden Secrets
      The surface of Venus is an inferno with temperatures hot enough to melt lead. This image is a composite of data from NASA’s Magellan spacecraft and Pioneer Venus Orbiter. Credits:
      NASA/JPL-Caltech NASA’s DAVINCI — Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging — mission embodies the spirit of innovation and exploration that its namesake, Leonardo da Vinci, was famous for.
      Scheduled to launch in the early 2030s, DAVINCI will explore Venus with both a spacecraft and a descent probe. DAVINCI’s probe will be the first in the 21st century to brave Venus’ atmosphere as it descends from above the planet’s clouds down to its surface. Two other missions, NASA’s VERITAS and ESA’s (European Space Agency) Envision, will also explore Venus in the 2030s from the planet’s orbit.
      The DAVINCI spacecraft will study Venus’ clouds and highlands during two flybys. It also will release a spherical probe, about 3 feet wide, that will plunge through the planet’s thick atmosphere and corrosive clouds, taking measurements and capturing high-resolution images of the Venusian surface as it descends below the clouds.
      Here are some of DAVINCI’s coming “firsts” in Venus exploration:
      Exploring Solar System’s One-of-a-Kind Terrain  
      The DAVINCI mission will be the first to closely explore Alpha Regio, a region known as a “tessera.” So far found only on Venus, where they make up about 8% of the surface, tesserae are highland regions similar in appearance to rugged mountains on Earth. Previous missions discovered these features using radar instruments, but of the many international spacecraft that dove through Venus’ atmosphere between 1966 and 1985, none studied or photographed tesserae.
      Thought to be ancient continents, tesserae like Alpha Regio may be among the oldest surfaces on the planet, offering scientists access to rocks that are billions of years old.
      By studying these rocks from above Alpha Regio, DAVINCI scientists may learn whether ancient Venus had continents and oceans, and how water may have influenced the surface.
      Photographing One of the Oldest Surfaces on Venus
      The DAVINCI probe will capture the first close-up views of Alpha Regio with its infrared and optical cameras; these will also be the first photos of the planet’s surface taken in more than 40 years.
      With surface temperatures reaching 900° F and air pressure 90 times that of Earth’s, Venus’ harsh environment makes exploration challenging, while its opaque atmosphere obscures direct views. Typically, scientists rely on radar instruments from Earth or Venus-orbiting spacecraft to study its terrain.
      But DAVINCI’s probe will descend through the atmosphere and below the clouds for a clear view of the mountains and plains. It will capture images comparable to an airplane’s landing view of Earth’s surface. Scientists will use the photos to compile 3D maps of Alpha Regio that will provide more detail than ever of Venus’ terrain, helping them look for rocks that are usually only made in association with water.
      Unveiling Secrets of Venus’ Mysterious Lower Atmosphere
      The DAVINCI mission will be the first to analyze the chemical composition of Venus’ lower atmosphere through measurements taken at regular intervals, starting from approximately 90,000 feet above the surface and continuing until just before impact.
      This region is critical because it contains gases and chemical compounds that may originate from Venus’ lower clouds, surface, or even subsurface.
      For example, sulfur compounds detected here could indicate whether Venusian volcanoes are currently active or were active in the recent past. Noble gases (like helium or xenon), on the other hand, remain chemically inert and maintain stable concentrations, offering invaluable clues about Venus’ ancient history, such as the planet’s past water inventory.
      By comparing Venus’ noble gas composition with that of Earth and Mars, scientists can better understand why these planets — despite forming from similar starting materials — evolved into dramatically different worlds.
      Moreover, DAVINCI’s measurements of isotopes and trace gases in the lower atmosphere will shed light on Venus’ water history, from ancient times to the present, and the processes that triggered the planet’s extreme greenhouse effect.
      State-of-the-Art Technology to Study Venus in Detail
      Thanks to modern technology, the DAVINCI probe will be able to do things 1980s-era spacecraft couldn’t.
      The descent probe will be better equipped than previous probes to protect the sensitive electronics inside of it, as it will be lined on the inside with high-temperature, multi-layer insulation — layers of advanced ceramic and silica fabrics separated by aluminum sheets.
      Venus’ super thick atmosphere will slow the probe’s descent, but a parachute will also be released to slow it down further. Most Earth-friendly parachute fabrics, like nylon, would dissolve in Venus’ sulfuric acid clouds, so DAVINCI will have to use a different type of material than previous Venus missions did: one that’s resistant to acids and five times stronger than steel.

      Read More: Old Data Yields New Secrets as NASA’s DAVINCI Preps for Venus Trip

      By Lauren Colvin, with Lonnie Shekhtman
      NASA’s Goddard Space Flight Center, Greenbelt, Md.

      NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is the principal investigator institution for DAVINCI and will perform project management for the mission, provide science instruments, as well as project systems engineering to develop the in-situ probe flight system that will enter the atmosphere of Venus. Goddard also leads the overall science for the mission with an external science team from across the United States. Lockheed Martin Space in Denver, Colorado, will build the carrier/relay spacecraft. DAVINCI is a mission within the Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington.
      View the full article
    • By NASA
      6 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      With one of its solar arrays deployed, NASA’s Lunar Trailblazer sits in a clean room at Lockheed Martin Space. The large silver grate attached to the spacecraft is the radiator for HVM³, one of two instruments that the mission will use to better understand the lunar water cycle.Lockheed Martin Space There’s water on the Moon, but scientists only have a general idea of where it is and what form it is in. A trailblazing NASA mission will get some answers.
      When NASA’s Lunar Trailblazer begins orbiting the Moon next year, it will help resolve an enduring mystery: Where is the Moon’s water? Scientists have seen signs suggesting it exists even where temperatures soar on the lunar surface, and there’s good reason to believe it can be found as surface ice in permanently shadowed craters, places that have not seen direct sunlight for billions of years. But, so far, there have been few definitive answers, and a full understanding of the nature of the Moon’s water cycle remains stubbornly out of reach.
      This is where Lunar Trailblazer comes in. Managed by NASA’s Jet Propulsion Laboratory and led by Caltech in Pasadena, California, the small satellite will map the Moon’s surface water in unprecedented detail to determine the water’s abundance, location, form, and how it changes over time.
      “Making high-resolution measurements of the type and amount of lunar water will help us understand the lunar water cycle, and it will provide clues to other questions, like how and when did Earth get its water,” said Bethany Ehlmann, principal investigator for Lunar Trailblazer at Caltech. “But understanding the inventory of lunar water is also important if we are to establish a sustained human and robotic presence on the Moon and beyond.”
      Future explorers could process lunar ice to create breathable oxygen or even fuel. And they could also conduct science. Using information from Lunar Trailblazer, future human or robotic scientific investigations could sample the ice for later study to determine where the water came from. For example, the presence of ammonia in ice samples may indicate the water came from comets; sulfur, on the other hand, could show that it was vented to the surface from the lunar interior when the Moon was young and volcanically active.
      This artist’s concept depicts NASA’s Lunar Trailblazer in lunar orbit about 60 miles (100 kilometers) from the surface of the Moon. The spacecraft weighs only 440 pounds (200 kilograms) and measures 11.5 feet (3.5 meters) wide when its solar panels are fully deployed.Lockheed Martin Space “In the future, scientists could analyze the ice in the interiors of permanently shadowed craters to learn more about the origins of water on the Moon,” said Rachel Klima, Lunar Trailblazer deputy principal investigator at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. “Like an ice core from a glacier on Earth can reveal the ancient history of our planet’s atmospheric composition, this pristine lunar ice could provide clues as to where that water came from and how and when it got there.”
      Understanding whether water molecules move freely across the surface of the Moon or are locked inside rock is also scientifically important. Water molecules could move from frosty “cold traps” to other locations throughout the lunar day. Frost heated by the Sun sublimates (turning from solid ice to a gas without going through a liquid phase), allowing the molecules to move as a gas to other cold locations, where they could form new frost as the Sun moves overhead. Knowing how water moves on the Moon could also lead to new insights into the water cycles on other airless bodies, such as asteroids
      Two Instruments, One Mission
      Two science instruments aboard the spacecraft will help unlock these secrets: the High-resolution Volatiles and Minerals Moon Mapper (HVM3) infrared spectrometer and the Lunar Thermal Mapper (LTM) infrared multispectral imager.
      Developed by JPL, HVM3 will detect and map the spectral fingerprints, or wavelengths of reflected sunlight, of minerals and the different forms of water on the lunar surface. The spectrometer can use faint reflected light from the walls of craters to see the floor of even permanently shadowed craters.
      The LTM instrument, which was built by the University of Oxford and funded by the UK Space Agency, will map the minerals and thermal properties of the same lunar landscape. Together they will create a picture of the abundance, location, and form of water while also tracking how its distribution changes over time.
      “The LTM instrument precisely maps the surface temperature of the Moon while the HVM3 instrument looks for the spectral signature of water molecules,” said Neil Bowles, instrument scientist for LTM at the University of Oxford. “Both instruments will allow us to understand how surface temperature affects water, improving our knowledge of the presence and distribution of these molecules on the Moon.”
      Weighing only 440 pounds (200 kilograms) and measuring 11.5 feet (3.5 meters) wide when its solar panels are fully deployed, Lunar Trailblazer will orbit the Moon about 60 miles (100 kilometers) from the surface. The mission was selected by NASA’s SIMPLEx (Small Innovative Missions for Planetary Exploration) program in 2019 and will hitch a ride on the same launch as the Intuitive Machines-2 delivery to the Moon through NASA’s Commercial Lunar Payload Services initiative. Lunar Trailblazer passed a critical operational readiness review in early October at Caltech after completing environmental testing in August at Lockheed Martin Space in Littleton, Colorado, where it was assembled.
      The orbiter and its science instruments are now being put through flight system software tests that simulate key aspects of launch, maneuvers, and the science mission while in orbit around the Moon. At the same time, the operations team led by IPAC at Caltech is conducting tests to simulate commanding, communication with NASA’s Deep Space Network, and navigation.
      More About Lunar Trailblazer
      Lunar Trailblazer is managed by JPL, and its science investigation and mission operations are led by Caltech with the mission operations center at IPAC. Managed for NASA by Caltech, JPL also provides system engineering, mission assurance, the HVM3 instrument, as well as mission design and navigation. Lockheed Martin Space provides the spacecraft, integrates the flight system, and supports operations under contract with Caltech.
      SIMPLEx mission investigations are managed by the Planetary Missions Program Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama, as part of the Discovery Program at NASA Headquarters in Washington. The program conducts space science investigations in the Planetary Science Division of NASA’s Science Mission Directorate at NASA Headquarters.
      For more information about Lunar Trailblazer, visit:
      https://www.jpl.nasa.gov/missions/lunar-trailblazer
      News Media Contacts
      Karen Fox / Molly Wasser
      NASA Headquarters, Washington
      202-358-1600
      karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
      Ian J. O’Neill
      Jet Propulsion Laboratory, Pasadena, Calif.
      818-354-2649
      ian.j.oneill@jpl.nasa.gov
      Gordon Squires
      IPAC, Pasadena, Calif.
      626-395-3121
      squires@ipac.caltech.edu
      2024-148
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      Details
      Last Updated Oct 29, 2024 Related Terms
      Lunar Trailblazer Earth's Moon Moons Planetary Science Planetary Science Division Science Mission Directorate Explore More
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