This picture was taken by the Rosetta spacecraft during its flight beside Comet 67P. Although it may look like a snowstorm, what we’re seeing are actually grains of cosmic dust passing in front of Rosetta’s camera.
Credit:
ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA