Space & Astronomy

Rosetta discovers molecular oxygen on comet

By T.K. Randall
October 29, 2015

Image: AI-generated (Midjourney) Picked up by the spacecraft's ROSINA mass spectrometers, the presence of molecular oxygen around the comet came as something of a surprise to researchers because it is usually quick to react with other chemicals and therefore should not exist on its own in such significant quantities.

In total oxygen is thought to make up around 3.8% of the molecules swarming around the comet.The mission scientists believe that the gas may be a remnant from the comet's formation several billion years ago after having become trapped inside small grains of ice and rock.

"This evidence of oxygen as an ancient substance will likely discredit some theoretical models of the formation of the Solar System," said project leader Professor Kathrin Altwegg.

The exact processes involved however remain something of a mystery and scientists admit that existing models will need to be revised to try and explain how this oxygen could still be there.

"We think this result is of interest beyond the cometary community because it forces us to rethink all of these models," said André Bieler, a physicist at the University of Michigan.

Source: Nature.com

Tags: Comet, 67P, Oxygen, Rosetta