Newly discovered chemical reaction could generate the gas instead, study suggests
Oxygen on comets might not date all the way back to the birth of the solar system.
Instead, interactions between water, particles streaming from the sun and grains of sand or rust on the comet’s surface could generate the gas. Those interactions could explain the surprising abundance of O2 detected in the fuzzy envelope of gas around comet 67P/Churyumov-Gerasimenko in 2015 (SN: 11/28/15, p. 6), researchers report May 8 in Nature Communications. Such reactions might also reveal how oxygen forms in other regions of space.
“Molecular oxygen is very hard to find out there in the universe,” says Caltech chemical engineer Konstantinos Giapis. When the Rosetta spacecraft detected oxygen around comet 67P, astronomers argued it must be primordial, trapped in water ice as the comet formed roughly 4.6