Oxygen leaking from comet surprises astronomers
Rosetta detects O2 molecules, probably from solar system’s birth, on 67P
SPACE SURPRISE Some of the gas streaming from comet 67P, seen in this September 11 picture from Rosetta, contains oxygen molecules trapped since the beginning of the solar system.
NAVCAM/Rosetta/ESA (CC BY-SA IGO 3.0)