Research
In LEAPS we study the evolution of airless planetary surfaces. We focus specifically on the alteration of planetary surfaces due to their exposure to planetary space, a phenomenon known as space weathering. This process is driven by solar wind irradiation and micrometeoroid bombardment and alters the microstructure, chemistry, and optical properties of material on airless surfaces.
We study space weathering using a variety of techniques. We analyze returned samples from the Apollo missions to the Moon as well as grains returned from asteroid Itokawa and asteroid Ryugu. We also simulate surface conditions in the laboratory using analog materials like meteorites. We use ion bombardment to mimic solar wind irradiation and laser irradiation to simulate micrometeoroid impacts. We study these samples using a combination of reflectance spectroscopy and electron beam techniques, primarily scanning electron microscopy and transmission electron microscopy. Our work is multi-faceted and relevant to several past, present, and future missions. Our current projects are below.
LEAPS is recruiting! There are funded positions available for two students to start in Fall 2024:
- The first project would focus on the analysis of volatiles in lunar samples and analog materials. This project would include the opportunity to develop new techniques and protocols for storing and analyzing samples that will be returned by the Artemis missions as part of the RASSLE NASA SSERVI team.
- The second project would include the electron microscopic analysis of analog materials exposed to simulated surface conditions on Venus to understand the weathering of these materials in the Venusian atmosphere. This project would provide an opportunity to work on a multidisciplinary team which combines remote sensing techniques, experimental simulations, and sample characterization that will be highly relevant to the upcoming exploration of Venus via NASA missions.
Applicants from a diverse set of backgrounds are encouraged to apply, particularly those with experience in electron microscopy or the analysis of Earth/Planetary materials in the laboratory. Learn more about the graduate program in the Department of Earth, Atmospheric, and Planetary Sciences at Purdue.
Understanding Space Weathering of Sulfide Minerals from Asteroid Itokawa
Dr. Thompson and Graduate Student Laura Chaves are currently studying sulfide-bearing dust particles from asteroid Itokawa returned by the Hayabusa mission to understand how these minerals experience space weathering. As significant constituents of meteorites, understanding how sulfides are altered is important for understanding the space weathering of asteroidal regoliths.
Space Weathering on the Moon Revealed by an Apollo 17 Core Sample
As part of a large consortium team, Dr. Thompson and Graduate Student James McFadden are studying how space weathering signatures vary with depth below the surface by analyzing grains from a newly-released Apollo 17 core sample. This work is important for understanding regolith mixing on the lunar surface.
Quantifying Lunar Water derived from the Solar Wind
Dr. Thompson and Graduate Student Alexander Kling will be studying the generation of water in space weathered lunar soils via the implantation of solar wind hydrogen. This work is critical for understanding the distribution of volatiles in the solar system and for the exploration of in situ resource utilization on the lunar surface.
Space Weathering on Mercury
Dr. Thompson and post-doc Dr. Nicolas Bott are simulating the space weathering environment at Mercury to understand how the unique, volatile-rich composition of that planetary surface affects space weathering signatures. Using a combination of sample analysis and VIS-NIR reflectance spectroscopy, this work leverages results from the MESSENGER mission and will provide more context for the ongoing BepiColombo mission.
Space Weathering on Asteroid Ryugu
Dr. Thompson and Graduate Student Lisette Melendez are studying particles returned from asteroid Ryugu returned by the Hayabusa2 mission to understand how space weathering affects carbonaceous asteroids. This work is critical for understanding the evolution of some of the most primitive objects in our solar system.