Oxygen discovered on Rosetta comet, stunning scientists

Scientists have for the first time detected oxygen on a comet, a finding that could upend theories about how the solar system was formed. Reporting their findings in the journal Nature on Wednesday, an international team said that they detected “a lot” of molecular oxygen in the cloud of gas, or coma, surrounding the nucleus of comet 67P/Churyumov–Gerasimenko. While molecular oxygen has been found in Jupiter and Saturn, it’s never been found on a comet. The neutral gas comas of most comets are composed largely of water, carbon monoxide and carbon dioxide. Related: Philae’s comet may host alien life, scientists say “It is the most surprising discovery we have made so far in 67P because oxygen was not among the