PARIS, March 21 (UPI) -- The European Space Agency's Rosetta spacecraft found molecular nitrogen on Comet 67P/Churyumov–Gerasimenko, offering possible clues about the dawn of the solar system.
The ESA said the discovery is particularly important because molecular nitrogen has long been considered the most common type of nitrogen available during the formative period of the solar system.
Molecular nitrogen is considered to be the primary source of the chemical element that was incorporated into gas planets. It is also widely found in the dense atmosphere of Titan, Saturn's moon, and the atmospheres and icy surfaces of Triton, Pluto and Neptune's moon, the ESA said.
"It is in these cold outer reaches of our solar system in which the family of comets that includes Rosetta's comet is believed to have formed," the ESA said on its blog.
The results are based on 138 measurements taken by Rosetta when it was about six miles from the comet in October.
"Identifying molecular nitrogen places important constraints on the conditions in which the comet formed, because it requires very low temperatures to become trapped in ice," Martin Rubin of the University of Bern said in a paper detailing the discovery, published in Science.