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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.
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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
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By NASA
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
The Orion Environmental Test Article photographed inside the Thermal Vacuum Chamber on April 11, 2024, in the Space Environments Complex at NASA’s Neil Armstrong Test Facility in Sandusky, Ohio. Credit: NASA/Quentin Schwinn Making the voyage 1.4 million miles around the Moon and back — the farthest a spacecraft built for humans has ever gone — the Orion spacecraft has faced a battery of tests over the years. Though Orion successfully proved its capabilities in the harsh environment of space during the Artemis I mission, Orion’s evaluation did not end at splashdown.
The crew module, now known as the Orion Environmental Test Article (ETA), returned to NASA’s Neil Armstrong Test Facility in Sandusky, Ohio, in January 2024 and completed an 11-month test campaign necessary for the safety and success of Artemis II, the first crewed mission under NASA’s Artemis campaign.
Engineers and technicians from NASA and Lockheed Martin subjected the test article to the extreme conditions Orion may experience in a launch abort scenario. In the event of an emergency, Orion — and astronauts inside — will jettison away from the SLS (Space Launch System) rocket for a safe landing in the ocean.
Experts at NASA’s Neil Armstrong Test Facility in Sandusky, Ohio, conducted a lightning test, which simulates the electromagnetic effects of a lightning strike to the vehicle on the launch pad awaiting liftoff. The Feb. 20, 2024 test proved the grounding path of the vehicle is operating as designed and protecting the vehicle from damage to any of its equipment or systems. Credit: NASA/Quentin Schwinn Experts installed NASA’s Launch Abort System, designed to carry the crew to safety in the event of an emergency during launch or ascent. The Orion test article was subjected to acoustic levels simulating both a nominal ascent and a launch abort scenario. The acoustic test chamber at NASA’s Neil Armstrong Test Facility in Sandusky, Ohio, blasted the test article at a volume of almost 164 decibels on Sept. 9, 2024. Credit: NASA/Jordan Salkin On Nov. 11, 2024, experts successfully at NASA’s Neil Armstrong Test Facility completed the docking mechanism jettison test, designed to connect and disconnect the Orion spacecraft to Gateway, a small space station that will orbit the Moon. They also completed the forward bay cover jettison test on Nov. 23, 2024, which is the last piece that must eject right before parachutes deploy, and successfully tested Orion’s uprighting system. Credit: NASA/Jordan Salkin “This event would be the maximum stress and highest load that any of the systems would see,” said Robert Overy, Orion ETA project manager, NASA’s Glenn Research Center in Cleveland. “We’re taking a proven vehicle from a successful flight and pushing it to its limits. The safety of the astronaut crew depends on this test campaign.”
Experts conducted tests that simulated the noise levels of an abort during launch in addition to the electromagnetic effects of lightning strikes. The test campaign also jettisoned the test article’s docking module and parachute covers, as well as the crew module uprighting system, which consists of five airbags on top of the spacecraft that inflate upon splashdown.
“It’s been a successful test campaign,” Overy said. “The data has matched the prediction models, and everything operated as expected after being subjected to nominal and launch abort acoustic levels. We are still analyzing data, but the preliminary results show the vehicle and facility operated as desired.”
On. Nov. 23, 2024, after subjecting the Orion test article to launch abort-level acoustics, experts tested the functionality of the forward bay cover, which is the last piece that must eject before parachutes deploy. Credit: NASA/Jordan Salkin and Quentin Schwinn Testing Orion at such high acoustic levels was a major milestone for Artemis. The Reverberant Acoustic Test Facility, the world’s most powerful spacecraft acoustic test chamber, was built in 2011 in anticipation of this specific test campaign.
“These tests are absolutely critical because we have to complete all of these tests to say the spacecraft design is safe and we’re ready to fly a crew for the first time on Artemis II,” said Michael See, ETA vehicle manager, Orion Program. “This is the first time we’ve been able to test a spacecraft on the ground in such an extreme abort-level acoustic environment.”
The Orion Environmental Test Article with Launch Abort System installed moves to the Reverberant Acoustic Test Facility, the most powerful spacecraft acoustic test chamber in the world, on Sept. 9, 2024, at NASA’s Neil Armstrong Test Facility in Sandusky, Ohio. Credit: NASA/Jordan Salkin and Quentin Schwinn Part of NASA Glenn, Armstrong Test Facility is home to the world’s largest and most powerful space environment simulation chambers capable of testing full-sized spacecraft for all the extreme conditions of launch and spaceflight. The facility not only houses an acoustic test chamber, but also a thermal-vacuum chamber and spacecraft vibration system.
“The facility is unique because there’s no other place in the world capable of testing spacecraft like this,” Overy said. “Armstrong Test Facility is a one-stop-shop for all your testing needs to prepare your spacecraft for the severe and challenging journey to and from space.”
Orion’s Round-Trip Journey to Ohio
This is not the first time Orion has been inside the walls of the Space Environments Complex at Armstrong Test Facility. The spacecraft underwent mission-critical testing in 2019, where it was subjected to extreme temperatures and an electromagnetic environment before it launched on Artemis I in 2022.
“I remember when it first arrived, the gravity of its importance really hit home,” said Joshua Pawlak, test manager, NASA Glenn. “I thought to myself, on future Artemis missions, astronauts will be inside Orion heading to the Moon, and they’ll be depending on it for survival.”
Pawlak was a mechanical test engineer when Orion made its first trip to the Sandusky facility. He participated in planning and coordinating testing of the vehicle and trained personnel. He managed the vehicle from the moment it arrived, through testing, and up until it departed for NASA’s Kennedy Space Center in Florida.
Joshua Pawlak poses in front of the Artemis I Space Launch System rocket on Nov. 16, 2022, in Cape Canaveral, Florida. Credit: Joshua Pawlak “When it returned, I felt like I had a small part in this really big and exciting thing,” Pawlak said. “Seeing it come back blackened and scarred from the harsh environment of space was incredible. Space is not a friendly space, and I felt proud knowing that if there were astronauts on that vehicle, they would have survived.
After the Orion test article departs from Glenn, it will head to Kennedy for additional testing.
“When Artemis II launches and those astronauts are sitting on board, I’ll know that I did everything I could to ensure the vehicle is ready for them and going to perform as expected,” Pawlak said. “That’s why I do what I do.”
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By NASA
On Thursday, Dec. 5, 2024, a team returns the Artemis II Orion spacecraft to the Final Assembly and Test cell from a vacuum chamber inside the Neil A. Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida where it underwent vacuum testing. NASA/Eric Hernandez NASA’s Orion spacecraft for the Artemis II test flight returned to the Final Assembly and System Testing (FAST) cell following completion of the second round of vacuum chamber testing on Dec. 5 inside the Neil A. Armstrong Operations and Checkout Building at NASA’s Kennedy Space Center in Florida.
After returning to the FAST cell, the four main batteries – which supply power to many Orion systems – were installed in the crew module. The batteries returned to NASA Kennedy from their supplier, EaglePicher Technologies, earlier this month. Solar array wings will also be installed onto the spacecraft by international partner ESA (European Space Agency) and its contractor Airbus in early 2025.
The Artemis II test flight will be NASA’s first mission with crew under the Artemis campaign, sending NASA astronauts Reid Wiseman, Victor Glover, and Christina Koch, as well as CSA (Canadian Space Agency) astronaut Jeremy Hansen, on a 10-day journey around the Moon and back.
Image credit: NASA/Eric Hernandez
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