European Space Agency’s Rosetta space probe has spotted molecular oxygen in the gas spewing from comet 67P/Churyumov-Gerasimenko. This finding has forced space scientists to rethink the ingredients thought to be present during the early days of the solar system.

Astronomers are particularly wondering about the factors that didn’t allow the oxygen to get annihilated during the formation of the solar system. Molecular oxygen reacts spontaneously with hydrogen, something which was present in abundance when the sun and the planets were formed. The existing models of solar system suggest that molecular oxygen must have disappeared when 67P was formed i.e. around 4.6 billion years back.

Andre Bieler, one of the lead authors of the study and a research fellow from the University of Michigan, said that for them detecting oxygen on the comet was a huge surprise.


While the findings of the new study are suggesting that the solar system models might need revision, Bieler and his colleague Kathrin Altwegg stated that at this moment they cannot speculate the kind of alterations those models require. Altwegg is a space scientist representing the University of Bern. The two couldn’t provide any information about the remodeling of our solar system as both of them are cometary scientists; they are not modeling experts.

The scientists said that they are currently trying to spot molecular oxygen in the Giotto spacecraft observation of Halley’s Comet (the event took place in 1986). For those who don’t know: it’s the only other comet to have a close-up view from a probe.

Here, it must be mentioned that spectral lines containing oxygen are not prominent enough to be spotted from the Earth’s surface. What this means is that there’s a possibility that presence of molecular oxygen might be a common feature of several other comets, but due to the excessive faintness of the spectral lines the theory cannot be confirmed.

ESA’s Rosetta has been following 67P for over a year. During this phase, the probe has spotted several elements in the coma of the comet. For those who don’t know: the term coma is used for the gas cloud around a comet’s rocky nucleus. Examples of elements detected by Rosetta include carbon dioxide, carbon monoxide, and water. All these elements are found in other comets observed by the scientists.