Breathe easier, budding astronauts, it turns out there are oxygen molecules in space. In fact, there are some just 1,500 light-years away, in a star-forming region of the Orion nebula, reports Live Science. Researchers think the oxygen comes from water molecules that coat tiny grains of space dust; when the sun melts the water, oxygen molecules are released. "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," said a NASA scientist.
Oxygen is the third-most common element in the universe, but so far scientists have only been able to detect oxygen atoms, usually around massive stars. The oxygen molecule—good old O2—has been much more elusive. Even now, researchers say the discovery by European Space Agency's Herschel Space Observatory is just a starting point. "But we didn't find large amounts of it," said the NASA scientist, "and still don't understand what is so special about the spots where we find it. The universe still holds many secrets." (More Herschel Space Observatory stories.)