There has been a flurry of activity surrounding comet 67p over the past few days. First, the biggest news. ESA’s Rosetta spacecraft has measured molecular nitrogen at Comet 67P/Churyumov-Gerasimenko.
This measurement provides some insight into the environment that gave birth to the comet. Molecular nitrogen is believed to have been the most common type of nitrogen when our solar system began to take shape. And, it’s also the main source of nitrogen in our solar system’s gas giants. It makes up large parts of the atmosphere on Titan, Pluto and Neptune’s moon Triton.
The measurements point to Comet 67P forming at very low temperatures. Researchers believe it was born in the Kuiper Belt region.
“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.
Varying scenarios put the temperature comet 67p formed at anywhere between -220 degrees Celsius and -253 degrees celsius.
“This very low-temperature process is similar to how we think Pluto and Triton have developed their nitrogen-rich ice and is consistent with the comet originating from the Kuiper Belt,” Martin said.
Could comets like Comet 67P be responsible for nitrogen in our atmosphere? Researchers say comets may have been responsible for some of it, but this new study suggests Comet 67P and others like it were not responsible.
The leading theory for Earth’s nitrogen is plate tectonics (volcanoes).
ESA scientists have spent more than a week sending signals to the Philae lander. There’s still no response. It could still be too cold, or the lander doesn’t have enough sunlight to power up.
DLR Project Manager Stephan Ulamec said it was a “very early attempt.” The team “will repeat this process until we receive a response from Philae. We have to be patient,” said Ulamec.
On Friday, the communication unit on Rosetta was turned off. The scientists at DLR will try again sometime during the first half of April. That’s the next best opportunity to receive a return signal from the lander.
New commands were sent to Philae on March 17th. Officials want the Philae lander to more effectively divide the available solar power between heating and communications.
“We are sure that the communication unit on the orbiter worked, but whether Philae has received the new commands, we do not yet know,” said Koen Geurts, a member of the control room team at DLR. Philae could have received the commands, but not have enough power to send a responding signal back to Rosetta. Conditions should be good enough by summer for Philae to wake up.
There’s a lot scientists just don’t know about Philae. Are its batteries charging? Did it even survive the extremely low temperatures?
How Gas Jets Are Affecting Comet 67P’s Rotation
Comet 67P takes 12.4 hours to complete one rotation. But, scientists have noticed that slowing by nearly one second a 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 at a lecture at the Royal Aeronautical Society last week.
Want to learn more about how the ESA landed on Comet 67P? Check out the lecture below.