Gravity-Dominated Hit and Run Collisions in Solar System Formation

Researchers supported in part by the NASA Astrobiology program are providing new insight into the late stages of solar system formation. The team developed empirical relationships to understand the processes behind accretion and erosion when large planetary bodies of varying compositions collide – including bodies that are rich in water. The study also focuses on the fine line between collisions where two bodies merge together, and those that result in a ‘hit-and-run’ scenario.

The results indicate that hit-and-run collisions occur across a wider range of impact angles than previously thought. The team provides an algorithm for incorporating their model into N-body planet formation simulations.

The study, “Gravity-dominated Collisions: A Model for the Largest Remnant Masses with Treatment for “Hit and Run” and Density Stratification,” was published in The Astrophysical Journal.

The work was supported by the Nexus for Exoplanet System Science (NExSS).  NExSS is a NASA  research coordination network supported in part by the  NASA Astrobiology Program. This program element is shared between NASA’s Planetary Science Division (PSD) and the Astrophysics Division. This research is a critical part of NASA’s work to understand the Universe, advance human exploration, and inspire the next generation. As NASA’s Artemis program moves forward with human exploration of the Moon, the search for life on other worlds remains a top priority for the agency.

Reference: “Gravity-dominated Collisions: A Model for the Largest Remnant Masses with Treatment for “Hit and Run” and Density Stratification” by Travis S. J. Gabriel, Alan P. Jackson, Erik Asphaug, Andreas Reufer, Martin Jutzi and Willy Benz, 24 March 2020, The Astrophysical Journal.
DOI: 10.3847/1538-4357/ab528d