Oxygen is the 3rd most common gas in the Universe.
So it is surprising that Molecular Oxygen has only just been
discovered in space, after decades of searching.
I assume that Molecular Oxygen means 02?
The 02 standing for two individual atoms of Oxygen in combination. Which gives us the air we breath.
Anyway astronomers having searched for one of the most abundant gasses in the Universe for
decades without success, have finally achieved fame, using that amazing European Telescope- Herschel.
PASADENA, Calif. 08.01.11– The Herschel Space Observatory's large telescope and state-of-the-art infrared detectors have provided the first confirmed finding of oxygen molecules in space. The molecules were discovered in the ORION star-forming complex.
Individual atoms of oxygen are common in space, particularly around massive stars. But molecular oxygen, which makes up about 20 percent of the air we breathe, has eluded astronomers until now.
"Oxygen gas was discovered in the 1770s, but it's taken us more than 230 years to finally say with certainty that this very simple molecule exists in space."
http://www.nasa.gov/mission_pages/herschel/news/herschel20110801.html