PASADENA, Calif., Aug. 2 (UPI) -- NASA says instruments on board the Herschel Space Observatory have provided the first confirmed finding of oxygen molecules in space.
While individual atoms of oxygen are common in space, particularly around massive stars, molecular oxygen, which makes up about 20 percent of the Earth's atmosphere, has eluded astronomers until now, a NASA release said Monday.
"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 Paul Goldsmith, Herschel project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Goldsmith and his colleagues theorize the oxygen discovered in the Orion star-forming complex is locked up in water ice coating tiny dust grains, and is only released after starlight warms the icy grains and releases water that is then converted into oxygen molecules.
"This explains where some of the oxygen might be hiding," said Goldsmith. "But we didn't find large amounts of it, and still don't understand what is so special about the spots where we find it. The universe still holds many secrets."
Researchers say they'll hunt for more oxygen in other star-forming regions.
"Oxygen is the third most common element in the universe and its molecular form must be abundant in space," said Bill Danchi, Herschel program scientist at NASA headquarters in Washington. "Herschel is proving a powerful tool to probe this unsolved mystery."
