Congratulations to Dr. Caleb Gimar!
We are proud to announce that Caleb Gimar has successfully defended his dissertation,
“From the Moon to Charon: Mission-Inspired Laboratory Investigations into Space Weathering and Polar Reddening.”
Date: Friday, October 17, 2025
Advisor: Dr. Ujjwal Raut
Recent spacecraft observations have revealed that small Solar System bodies such as the Moon and Pluto’s moon Charon exhibit surface properties shaped by their unique space environments. Caleb’s dissertation explores how processes like solar wind irradiation, micrometeoroid bombardment, and interplanetary photon exposure affect surface albedo and spectral reflectance.
Through a series of laboratory-based experiments inspired by lunar and planetary missions, his research provides new insights into:
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Far-ultraviolet (FUV) reflectance of lunar simulants and Apollo samples, revealing the role of space weathering and titanium-bearing minerals.
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Comparative studies of Apollo soils, showing that FUV spectra may not fully distinguish between highly weathered mare and highland terrains.
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Spectroscopy of ethane ice relevant to Charon’s poles, demonstrating a potential “thermal reddening” process contributing to the moon’s distinctive coloration.
Caleb’s work bridges mission data and laboratory science, advancing our understanding of planetary surface evolution — from the Moon to the outer reaches of the Solar System.
Please join us in congratulating Dr. Caleb Gimar on this outstanding achievement!
