Members Can Post Anonymously On This Site
LIVE Launch:Rocket Lab Electron - They Go Up So Fast
-
Similar Topics
-
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
Share
Details
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
Article 1 hour ago 5 min read Cutting-Edge Satellite Tracks Lake Water Levels in Ohio River Basin
Article 3 days ago 5 min read NASA Mars Orbiter Spots Retired InSight Lander to Study Dust Movement
Article 4 days ago Keep Exploring Discover More Topics From NASA
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
-
By USH
The ongoing mystery and debate surrounding UFO and drone sightings across the U.S. continue to captivate public attention. The lack of transparency and definitive answers from government agencies combined with the apparent absence of military action against these drones, has fueled speculation about possible cover-ups or incompetence.
Local, county, and state governments seem to have no knowledge of who is operating these drones, where they originate, or their purpose. Despite this, officials confidently assert that "there is no credible threat." This raises the question: how can they be so certain? The reality suggests they cannot.
Recently, the Pentagon issued a statement following claims by a New Jersey congressman that Iran had deployed a "mothership" off the U.S. East Coast, launching drones. The Pentagon denied any military origin for the drones and ruled out links to known foreign entities, but questions persist about whether critical information is being withheld.
If these drones are not linked to Iran, the U.S., Russia, China, or any other nation, some experts propose they may be part of clandestine "deep state" programs. These programs could involve advanced aerospace technologies being tested by private companies under classified initiatives.
Witness accounts, including those from a New Jersey sheriff and Coast Guard officials, suggest the drones exhibit highly unusual behaviors. These include emerging from the ocean and performing movements like abrupt 90-degree turns—characteristics that could imply the use of advanced propulsion systems not publicly known.
Another theory posits that the drones may not be physical objects at all but rather holographic projections, akin to the controversial "Project Blue Beam" concept. If true, this would explain why attempts to intercept them could fail—they might not physically exist.
The sheer number, endurance, and sophistication of these drones hint at a coordinated operation. Some theorists believe this might be part of a psychological operation designed to distract from pressing political, economic, or social issues. The timing of such events often appears suspiciously aligned with periods of public, economic unrest or uncertainty.
In the event that the "deep state" is orchestrating these phenomena, some fear it could be a prelude to a false flag operation, with motives and consequences yet to be revealed.
The situation remains shrouded in speculation, leaving the public to grapple with more questions than answers.
View the full article
-
By NASA
3 Min Read They Grow So Fast: Moon Tree Progress Since NASA’s Artemis I Mission
In the two years since NASA’s Orion spacecraft returned to Earth with more than 2,000 tree seedlings sourced in a partnership with USDA Forest Service, Artemis I Moon trees have taken root at 236 locations across the contiguous United States. Organizations are cultivating more than just trees, as they nurture community connections, spark curiosity about space, and foster a deeper understanding of NASA’s missions.
Universities, federal agencies, museums, and other organizations who were selected to be Moon tree recipients have branched out to provide their community unique engagements with their seedling.
Children sitting in a circle around a newly planted Moon tree and learning about NASA’s Artemis I mission. Adria Gillespie “Through class visits to the tree, students have gained a lot of interest in caring for the tree, and their curiosity for the unknown in outer space sparked them to do research of their own to get answers to their inquiries,” said Adria Gillespie, the district science coach at Greenfield Union School District in Greenfield, California.
The presence of a Moon tree at schools has blossomed into more student engagements surrounding NASA’s missions. Along with planting their American Sycamore, students from Eagle Pointe Elementary in Plainfield, Illinois, are participating in a Lunar Quest club to learn about NASA and engage in a simulated field trip to the Moon.
Eagle Pointe Elementary students also took part in a planting ceremony for their seedling, where they buried a time capsule with the seed, and established a student committee responsible for caring for their Moon tree.
At Marshall STEMM Academy in Toledo, Ohio, second grade students were assigned reading activities associated with their Moon tree, fourth graders created Moon tree presentations to show the school, and students engaged with city leaders and school board members to provide a Moon tree dedication.
Two individuals planting a Moon tree. Brandon Dillman A seedling sent to The Gathering Garden in Mount Gilead, North Carolina, is cared for by community volunteers. Lessons with local schools and 4-H clubs, as well as the establishment of newsletters and social media to maintain updates, have sprouted from The Gathering Garden’s Loblolly Pine.
Sprucing Up the Moon Trees’ Environment
In addition to nurturing their Moon tree, many communities have planted other trees alongside their seedling to foster a healthier environment. In Castro Valley, California, a non-profit called ForestR planted oak, fir, and sequoia trees to nestle their seedling among a tree “family.”
New homes for additional Moon tree seedlings are being identified each season through Fall 2025. Communities continue to track how the impact of NASA’s science and innovation grows alongside their Moon trees.
NASA’s “new generation” Moon trees originally blossomed from NASA’s Apollo 14 mission, where NASA astronaut Stuart Roosa carried tree seeds into lunar orbit. NASA’s Next Generation STEM project partnered with USDA Forest Service to bring Moon trees to selected organizations. As NASA continues to work for the benefit of all, its Moon trees have demonstrated how one tiny seed can sprout positive change for communities, the environment, and education.
Learn more about NASA’s STEM engagements: https://stem.nasa.gov
Keep Exploring Discover More Topics From NASA
NASA STEM Artemis Moon Trees
ARTEMIS I
Outside the Classroom
For Kids and Students
View the full article
-
By European Space Agency
The Copernicus Sentinel-1C satellite is ready for liftoff! Tune in to ESA WebTV on 4 December from 22:00 CET to watch the satellite soar into space on a Vega-C rocket to be launched from Europe’s Spaceport in Kourou, French Guiana. Sentinel-1C is scheduled to liftoff at 22:20 CET.
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.