In 2014, after a ten-year journey, the European Space Agency’s Rosetta mission reached the chicken winged-shaped comet 67P/Churyumov–Gerasimenko. Since then, the probe has orbited the comet as it flies farther and farther away from the sun—slowly losing power as a dwindling amount of our star's rays illuminate its solar panels. Now 575 kilometers from the sun, the ESA is sending the craft out in style, with plans to crash land it on 67P tomorrow, collecting scientific data all the way down. And the ESA will broadcast all the action via livestream on its website.
The Rosetta mission is best known for the trials and travails of its Philae lander. In November 2014, after reaching the comet, Rosetta deployed the washing machine-sized craft. But one of its harpoon anchors malfunctioned, causing the probe to bounce. It eventually landed in the shadow of a cliff where it could not receive enough sunlight to power its instruments. But its exact whereabouts were not known until Rosetta spotted it earlier this month.
The satellite has made increasingly close orbits of 67P, taking photos of the surface and measuring the space rock's atmosphere. “What we are doing at the moment is actually more complicated than when we deployed Philae itself,” Matt Taylor, a mission scientist tells Davis. “I think [finding Philae] is a nice prelude for the end of the mission. It’s bloody exciting.”
Project scientists will set Rosetta on a collision course with 67P at 4:50 PM EST today, according to the ESA. But it will take a 13.5 hour free fall for the craft to actually hit the comet's surface. Around 6:40 AM EST on September 30, the satellite's venture will come to an end near a 426-foot wide pit named Ma’at, roughly 1.2 miles away from Philae’s final resting place, Elizabeth Gibney reports for Nature. The crash itself will not be particularly big. Rosetta is expected to hit the comet at roughly walking speed.
The hope is that Rosetta will take some incredible images on its final descent with resolutions as close as several millimeters per pixel. Gibney reports that researchers are interested in getting images of the walls of the Ma’at crater, and that the onboard ROSINA science package will get readings on gas, dust, temperature and ionized particles. “We’re literally diving into the unknown, entering a new zone for science,” mission scientist Laurence O’Rourke tells Maddie Stone at Gizmodo.
“Rosetta will live on because we’re going to get loads of great science out of the data that’s been taken,” Taylor tells Stone. “I think we’ve done all that we can with the spacecraft, and I haven’t got any regrets.”
So set your alarm clocks for tomorrow morning and catch all the action on the ESA's website.