Farewell Philae: ESA Switches Off Comms Link to Comet Lander
Scientists bid the Philae comet lander farewell as communications link to the lander was switched off.
The European Space Agency (ESA) shut off the electrical support system (ESS) processor unit of the Rosetta spacecraft, which has been searching for the Philae lander and relaying communications from the space probe.
— Philae Lander (@Philae2014) July 26, 2016
"I'm far from Earth & Sun! I'd love to take memories of you with me," Philae wrote its final farewell message on Twitter.
"Please send me a postcard from home!"
Meanwhile, the Rosetta spacecraft will remain in orbit around Comet 67P/ Churyumov-Gerasimenko until Sept. 30, when ESA will crash the spacecraft into the comet's surface to capture close-up photos and data from the comet.
"Switching off the ESS is part of the preparations for Rosetta's end of mission," the Rosetta team said in a press release published on the mission website.
"By the end of July 2016, the spacecraft will be some 520 million km from the Sun, and will start facing a significant loss of power - about 4W per day."
Philae made its historic touchdown on Comet 67P/ Churyumov-Gerasimenko on Nov. 12, 2014 with the Rosetta spacecraft. Its task was to gather information about the comet and transmit images. Unfortunately, the landing was not as smooth as expected, and the Rosetta team lost communication with the lander. Philae initially worked for about 60 hours before getting into hibernation mode, Space.com reports.
When Comet 67P moved closer to the sun, scientists were able to regain communications with Philae, and the lander made intermittent contacts with the Rosetta spacecraft, which was still orbiting the comet. However, the communications were too unstable to make any scientific observations.
After its brief contact with mission managers on July 9, 2015, Philae went into what ESA believed to be "eternal hibernation."
"In spite of this, the ESS was kept on until now in the unlikely chance that Philae would regain contact," the Rosetta team said in the same statement.
"Although Rosetta has reached altitudes well below 10 km over the surface of Comet 67P, however, no signal from the lander was received since July 2015."
According to the Rosetta team, the final hours of descent will enable the spacecraft to make once-in-a-lifetime measurements, including high-resolution imaging.
"This is the ultimate challenge for our teams and for our spacecraft," Patrick Martin, ESA Rosetta's mission manager said in a press release.
"And it will be a very fitting way to end the incredible and successful Rosetta mission."