Abstract by William Oldroyd
Physics and Astronomy
Thermal Equilibrium Depth Modeling for a Potential Hidden Population of Antarctic Meteorites
Iron meteorites are underrepresented in Antarctic collections compared with observed worldwide meteorite falls, which represent the actual population of meteorites striking Earth. Meteorites absorb solar flux while on the Antarctic ice sheet, possibly causing heating and downward tunneling. Ablation and ice sheet flow counteract this descent, pushing meteorites upward. Dense meteorites that absorb adequate thermal energy may sink and reach a shallow equilibrium depth. Using a pyranometer, we have measured solar flux at multiple depths in two deep field sites in Antarctica, in the 13-14 and 16-17 field seasons. We compare these data with laboratory analogues and model the thermal and physical interactions between meteorites and their surroundings. We find that a 30 cm snowfall results in an 80% drop in solar energy potentially raising equilibrium depth estimates and implying greater accessibility to buried meteorites. Recovering an additional meteorite population would increase our knowledge of solar system formation and composition.