04/08/2024
By Joanne Gagnon-Ketchen

Physics colloquium, Wednesday, April 10 at 4 p.m. in Olsen 102.

Benjamin P. Weiss, Robert R. Shrock Professor of Planetary Sciences, Department of Earth, Atmospheric, and Planetary Sciences (EAPS), Massachusetts Institute of Technology will give a talk on "Understanding the origin of metal worlds with the Psyche mission."

Abstract: Recently it has been realized the super-dense worlds are ubiquitous in the galaxy, ranging in size from iron-rich asteroids like (16) Psyche, to planet Mercury, to super-Earth exoplanets. How such worlds formed evolved are largely unknown. Here I describe how we are addressing this using laboratory magnetic measurements of iron meteorites and planned in situ observations from the recently launched NASA Discovery mission Psyche. Our meteorite measurements show that some early asteroids generated dynamo magnetic fields from churning of their liquid metallic cores. The Psyche mission will be the first spacecraft to visit a metal-rich body. Arriving in 2029, it will search for a remanent magnetic field and large metal-rich regions to test the hypothesis that the asteroid formed from the core of a melted body whose rocky exterior was stripped by impacts.

Bio: Weiss directs the MIT Paleomagnetism Laboratory and is the Chair of the Program in Planetary Sciences at MIT. Dr. Weiss received his BA in Physics from Amherst College in 1995. He then received his MS and PhD in Planetary Science and Geology from the California Institute of Technology in 2001 and 2003 respectively. He joined MIT in 2003 and became a Professor of Planetary Sciences in 2014. He was appointed the Robert R. Shrock Professor of Planetary Sciences in 2023. He studies the formation, evolution, and history of planetary bodies, with a focus on paleomagnetism and geomagnetism, geophysics, meteoritics, and habitability. Dr. Weiss has received several awards and felicitations in his career – he is the Deputy Principal Investigator for the NASA Psyche Mission and has an asteroid named after him (Asteroid 8069 Benweiss).