Evidence of Hydration Found on Asteroid Psyche by SwRI-Led Team

Evidence of Hydration Found on Asteroid Psyche by SwRI-Led Team
by Clarence Oxford
Los Angeles CA (SPX) Aug 14, 2024

A team led by the Southwest Research Institute (SwRI) has identified hydroxyl molecules on the surface of the metallic asteroid Psyche using data from NASA's James Webb Space Telescope. The discovery of these hydrated minerals suggests that Psyche has a more complex history than previously understood, providing key insights as NASA's Psyche spacecraft makes its way to the asteroid, currently orbiting the Sun between Mars and Jupiter.

Psyche, which spans approximately 140 miles in diameter, is among the largest objects in the main asteroid belt. Prior studies have indicated that Psyche is dense and predominantly metallic, possibly representing the exposed core of a planet that underwent a significant collision. On October 13, 2023, NASA launched the Psyche spacecraft, which is now on its 2.2 billion-mile journey, scheduled to arrive at the asteroid in August 2029.

"Using telescopes at different wavelengths of infrared light, the SwRI-led research will provide different but complementary information to what the Psyche spacecraft is designed to study," explained Dr. Tracy Becker of SwRI, the second author of a new paper in the American Astronomical Society's Planetary Science Journal that discusses these findings.

"Our understanding of solar system evolution is closely tied to interpretations of asteroid composition, particularly the M-class asteroids that contain higher concentrations of metal," stated Dr. Stephanie Jarmak from the Center for Astrophysics | Harvard and Smithsonian. Dr. Jarmak, the paper's lead author, conducted much of this research during her time at SwRI. "These asteroids were initially thought to be the exposed cores of differentiated planetesimals, a hypothesis based on their spectral similarity to iron meteorites."

The Webb telescope's data suggest the presence of hydroxyl and possibly water on Psyche's surface. The origin of these hydrated minerals could be from external sources such as impacts. However, if the hydration is native, Psyche's history may differ significantly from current models.

"Asteroids are remnants of the planetary formation process, and their compositions can vary based on their formation location within the solar nebula," said Dr. Anicia Arredondo of SwRI, another co-author. "If the hydration is endogenous, it might indicate that Psyche did not originate as the remnant core of a protoplanet. Instead, it could imply that Psyche formed beyond the 'snow line,' where temperatures were low enough for volatile compounds to condense into solids, before migrating to the outer main belt."

The variability in hydration features across observations suggests a heterogeneous distribution of hydrated minerals on Psyche's surface, pointing to a complex history potentially shaped by impacts from highly hydrated carbonaceous chondrite asteroids.

Understanding the composition and location of asteroids like Psyche provides crucial insights into the distribution and evolution of materials in the solar nebula. The distribution of water across our solar system may also guide the search for life in other solar systems, as water is essential for life on Earth.

NASA's Webb telescope, developed in collaboration with the European and Canadian space agencies, is managed by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy. The Psyche mission is led by Arizona State University, with NASA's Jet Propulsion Laboratory handling mission management, operations, and navigation.

Research Report:Estimate of water and hydroxyl abundance on asteroid (16) Psyche from JWST data