Although Rosetta's Philae lander has made it to the surface of comet 67P/Churyumov-Gerasimenko on Wednesday, the historic landing was not as smooth as it initially appeared.
The robotic lander encountered problems when its top-thruster, which was designed to counteract the recoil of impact and prevent the probe from bouncing back into space, did not work. The lander's twin harpoons that were meant to anchor it to the low-gravity comet also failed to deploy.
As a result of these malfunctions, the probe rebounded off of the comet soon after it landed on the surface. Results of magnetic field analysis indicate that the washing-machine sized craft hit 67P/C-G's surface like a bouncy ball.
The team behind the Rosetta Lander Magnetometer and Plasma Monitor (ROMAP) revealed that the probe first touched down on the comet's rugged surface at 15:33 UTC but it bounced back soaring over a kilometer back into space before it floated back again to the surface landing two hours later at 17:26. The probe bounced again for the second time and got back to the surface at 17:33 and finally settled.
"Magnetic field analysis revealed 3 landings at 15:33, 17:26 and 17:33 UTC," the team tweeted.
After bouncing off of the surface twice, the Philae touched down away from its target landing zone settling in a shadowy part near a cliff where it will only get one and a half hours of sunlight a day. Had it settled on its planned landing site, the probe would receive up to seven hours of sunlight per day.
The difference in the amount of sunlight that the robot will get is crucial because it needs to use solar power once its batteries have run out and the sunlight it gets will significantly impact how much work the Philae can do on the comet's surface. Another concern is that the probe is not anchored on the low-gravity surface.
Despite the hitches, the Philae has already started analyzing the composition of the comet and is sending scientific data it has gathered back on Earth. Philae's mission team cautiously activates more of the probe's instruments in order of the risks these pose with regards to Philae's position.
Philae has also sent home a panoramic shot of the craggy terrain of the comet. The image the European Space Agency (ESA) has shared was taken by the lander's CIVA-P imaging system and shows the 360 degree view around its final touchdown area.
