The European Space Agency (ESA) Rosetta spacecraft, currently orbiting Comet 67P/Churyumov–Gerasimenko has detected molecular nitrogen. This is the first time the substance has been detected at a comment, although it is something that researchers have hoped to find for some time. Previous detections of nitrogen have only occurred in cases where it was bound up with other compounds such as ammonia and hydrogen cyanide.

The form of molecular nitrogen is thought to have been the most common type when the Solar System was forming and to have been the main source of nitrogen involved in the creation of the gas giants. It is also present in the surface ice and atmosphere of Pluto’s moon Triton as well as Saturn’s moon, Titan.

It is in the same cold, distant reaches of the solar system that scientists think comets such as 67P/Churyumov–Gerasimenko were formed.

According to a statement from the ESA, “the new results are based on 138 measurements collected by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument, ROSINA, during 17–23 October 2014, when Rosetta was about 10 km from the centre of the comet.”

“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,” says Martin Rubin of the University of Bern, lead author of the paper presenting the results published today in the journal Science.

The trapping of molecular nitrogen is thought to have taken place in the interstellar nebula at temperatures comparable to those that trapped carbon monoxide in ice. Understanding the composition of the comet could help scientists to understand temperatures and other conditions at the time the solar system was formed.

It was also announced this week, at the Royal Aeronautical Society in London, that Comet 67P is slowing down and is starting to become more active. Normally the comet takes 12.4 hours to complete one rotation or “day”. According to the ESA the comet is now slowing down at a rate of about 1 second per day.

“The gas jets coming out of the comet – they are acting like thrusters and are slowing down the comet,” said flight director Andrea Accomazzo according to the BBC.

Navigators with the Rosetta mission track landmarks on the comet to check its rotation. These landmarks, in turn, help the ESA to plan Rosettas navigation. Last year the rotation was slowing by 33 milliseconds per day, but as it approaches the sun the comet is slowing further.

“OK, it’s not going to slow down completely – but this gives you an order of magnitude for the accuracy we’re now achieving with the navigation of the spacecraft around the comet,” said Accomazzo.

After four months there is still no word on Rosetta’s Philae lander. The robotic lander, which is still resting on the comet, did not respond to a wakeup call after eight days of attempts ending last week. ESA researchers are still hoping that the lander will resume sending data next month.

“Perhaps it is still too cold for the Philae lander to wake up on Comet 67P/Churyumov-Gerasimenko. Maybe its power resources are not yet sufficient to send a signal to the team at the DLR Lander Control Center,” the German Aerospace Centre (DLR) said according to Phys.org.

After landing, Philae had just enough power to complete a 54-hour roster of core experiments before powering down. Researchers now have to hope that the lander gets enough sun to power up again before Rosetta’s mission ends.