Asked by: Brian Hope, Birmingham
Surprisingly, yes. Earth’s atmosphere still contains oxygen up to about 700km altitude (the ISS orbits at 400km). At that altitude, oxygen exists as single atoms, rather than O2 molecules, and it is more reactive. Aluminium and stainless steel form a protective oxide layer and won’t corrode, but silver and iron corrode quickly in low orbit. In deep space, however, the lack of oxygen means that corrosion does not occur.