A new study by researchers at Southwest Research Institute (SwRI) and NASA’s Jet Propulsion Laboratory (JPL) offers insights into mysterious features on airless worlds, such as asteroids and moons. The research, published in The Planetary Science Journal, suggests that post-impact conditions, like those following a meteoroid impact, could produce liquid brines that temporarily flow along the surface of these celestial bodies.
Dr. Michael J. Poston from SwRI and Dr. Jennifer Scully from JPL led the team, which simulated the pressures experienced by ice on Vesta, one of the largest asteroids in our solar system, after an impact. They found that saltwater mixtures, or brines, stayed liquid and flowing for at least an hour, sufficient to cause erosion and landslides and potentially form unique geological features.
The study’s findings could help explain the origins of certain observed features on distant bodies, such as Europa’s smooth plains and Mars’ gullies, and build a stronger case for subsurface water in seemingly inhospitable locations in the solar system.
Unveiling the Mysteries of Airless Worlds: Insights into Flow Features and Subsurface Water
The surfaces of airless celestial bodies, such as asteroids and moons, have long fascinated scientists with their enigmatic features. A recent study co-led by Southwest Research Institute (SwRI) and NASA’s Jet Propulsion Laboratory (JPL) has shed light on the mysterious flow features observed on these bodies. The research, published in The Planetary Science Journal, proposes that post-impact conditions could produce liquid brines that temporarily flow along the surface, etching curved gullies and depositing fans of debris in crater walls.
Post-Impact Conditions and Liquid Brines
The study’s lead author, Dr. Michael J. Poston from SwRI, and his team investigated how ice underneath the surface of an airless world could be excavated and melted by a meteoroid impact. They simulated the pressures that ice on Vesta, one of the largest asteroids in our solar system, experiences after such an impact. The researchers found that the liquid released from the subsurface could flow for a significant amount of time before refreezing. This discovery has significant implications for understanding the geological features observed on airless bodies.
The team modified a test chamber at JPL to rapidly decrease pressure over a liquid sample, simulating the dramatic drop in pressure as the temporary atmosphere created after an impact on an airless body like Vesta dissipates. The results showed that pure water froze too quickly in a vacuum to effect meaningful change, but salt and water mixtures, or brines, stayed liquid and flowing for at least one hour. This duration is sufficient for the brine to destabilize slopes on crater walls, cause erosion and landslides, and potentially form other unique geological features found on icy moons.
Implications for Understanding Geological Features
The findings of this study could help explain the origins of certain observed features on distant bodies, such as the smooth plains of Europa and the distinct “spider” feature in its Manannán crater. The research could also shed light on the various gullies and fan-shaped debris deposits on Mars. By understanding how liquid brines can flow on airless worlds, scientists may uncover evidence of subsurface water in seemingly inhospitable locations in the solar system.
The study’s lead author, Dr. Poston, emphasized that if these findings are consistent across dry and airless or thin-atmosphere bodies, it demonstrates that water existed on these worlds in the recent past. This, in turn, suggests that water might still be expelled from impacts, indicating that there may still be water to be found in the solar system.
The Quest for Subsurface Water
The discovery of subsurface water on airless worlds has significant implications for astrobiology and the search for life beyond Earth. If water exists or has existed on these bodies, it increases the likelihood of finding life or evidence of past life. The study’s findings contribute to a stronger case for the existence of subsurface water in seemingly inhospitable locations in the solar system.
The research was funded through a grant from NASA’s Discovery Data Analysis Program as part of an ongoing project led by JPL at the California Institute of Technology, Pasadena. As scientists continue to explore the mysteries of airless worlds, they may uncover more evidence of subsurface water and its role in shaping the geological features of these enigmatic bodies.
Future Directions and Implications
The study’s findings have significant implications for future missions, such as the NASA Europa Clipper mission, which will explore Jupiter’s moon Europa in detail. The discovery of liquid brines on airless worlds could inform the design of instruments and experiments to detect subsurface water and search for signs of life.
As scientists continue to unravel the mysteries of airless worlds, they may uncover more evidence of subsurface water and its role in shaping the geological features of these bodies. The study’s findings demonstrate that even in the most inhospitable environments, water can exist and play a crucial role in shaping the surface features of celestial bodies.
External Link: Click Here For More
