Thermophysical Diversity of Young Lunar Crater Ejecta Revealed with LRO Diviner Observations

Abstract

Young (1 m in diameter, (2) “clastic” ejecta with varying levels of vertical density stratification, and (3) “impact melts” with high thermal inertia materials buried under a layer of less dense material. These thermophysically derived classes correlate strongly with observed morphology in high-resolution images and polarimetric signatures in decimeter-wavelength radar, and their thermophysical properties evolve distinctly with crater age. This technique represents the first time impact melt in many forms can be quantitatively distinguished by its physical properties from other types of ejecta using remote-sensing data and could have applications in validating models of impact ejecta production and deposition.

Keywords

• Lunar craters
• Lunar surface
• Lunar impacts
• Lunar regolith
• Remote sensing
• Infrared astronomy