NEW YORK – Researchers from the University of Michigan and Bern revealed the unexpected discovery of oxygen in a comet spotted by the Rosetta spacecraft.

The European spacecraft Rosetta, launched in 2004, focuses on studying 67P/Churyumov–Gerasimenko, a comet with an orbital period of  6.45 years. After 11 years, the space probe has proved its value once again.

Measurements pointed out by the Rosetta indicate that oxygen molecules in the comet’s halo existed before its formation. According to scientist Andre Bieler of the University of Michigan, “This may have implications for mankind’s understanding of the chemistry involved in the formation of the Solar System some 4.6 billion years ago. We believe this oxygen is primordial, which means it is older than our Solar System”.

Not every comet in space shows and spheric shape. Some comets are irregular, due to the lack of gravity that should make them have an determined configuration. Copyright: ESA/Rosetta/NAVCAM, CC BY-SA IGO 3.0

Investigators previously indicated that oxygen on comets like the 67P didn’t exist. This new discovery is now making scientists rethink the elements present in our young solar system. The reason why the experts are starting to wonder what those elements actually were, is simple: oxygen wasn’t destroyed when the solar system was formed.

Oxygen is highly reactive to hydrogen, an element of which there was abundance of at the time when our planets and Sun were created. Therefore, current solar system models indicate that oxygen at its molecular level should have disappeared way before the 67P comet was created 4.6 billion years ago.

“It was a big surprise to actually detect the O2,” said Bieler in a briefing hosted by Nature journal. Although the discovery suggests the revision of these solar system models, Kathrin Altwegg, a space scientist at the University of Bern, said they could not speculate too much on what, exactly, would change about those models.

Despite the fact that Rosetta has detected elements such as water, carbon monoxide and carbon dioxide, molecular oxygen wasn’t expected at all. Because the discovery was unusual, scientists spent months ensuring that it wasn’t an instrument glitch before releasing the report.

Sources: Nature Journal