Real-time Observation of Polyimide Erosion in Very Low Earth Orbit (VLEO) and Its Impact on Space Environmental Effect on Materials

Superlow altitude test satellite (SLATS) was launched on Dec. 23, 2017 and recorded the lowest altitude for Earth observing satellite (167.4 km, Guinness World Record). SLATS carried the world first material erosion mission, atomic oxygen fluence sensor (AOFS), to measure polyimide erosion in real time in very low Earth orbit (VLEO) environment. This presentation describes the results of AOFS. It includes the correction method of shielding/shadowing effect by the SLATS fuselage, and enhancement of polyimide erosion by the simultaneous N2 collision in VLEO environment. The erosion yield (Ey) of polyimide, which has been believed to be 3.0E-24 cm3/atom in all altitudes as a reference value of material erosion, will also be re-evaluated based on the recently updated atmospheric model (MSIS2.0) and experimental results by SLATS/AOFS.