Rosetta finds oxygen on comet 67P in 'most surprising discovery to date'

[muriel_volestrangler]

Scientists on the Rosetta mission have found oxygen in the gas cloud around comet 67P in what they described as the most surprising discovery about the comet to date.

It is the first time that molecular oxygen - the form of the gas we breathe - has been detected on a comet, and points to a gentle birth for comet 67P some time before the formation of the solar system.

Measurements from the European Space Agency’s orbiting Rosetta probe show that oxygen is the fourth most abundant gas in the tenuous atmosphere of comet 67P / Churyumov-Gerasimenko, to use its full name, after water vapour, carbon monoxide and carbon dioxide.

“It’s actually the most surprising discovery we have made so far on 67P because oxygen was not among the molecules expected in a cometary coma,” said Kathrin Altwegg at the University of Bern.

http://www.theguardian.com/science/2015/oct/28/rosetta-finds-oxygen-on-comet-67p-in-most-surprising-discovery-to-date

Also: http://www.latimes.com/science/sciencenow/la-sci-sn-oxygen-rosetta-comet-20151027-story.html

Full Nature article:

The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density1. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn2, 3, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov–Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet’s formation, which is unexpected given the low upper limits from remote sensing observations4. Current Solar System formation models do not predict conditions that would allow this to occur.

http://www.nature.com/nature/journal/v526/n7575/full/nature15707.html

[Gregorian]

1. I'm waiting to see Jesus riding one of those.