|Rosetta’s lander Philae is safely on the surface of Comet 67P/Churyumov-Gerasimenko, as these first two CIVA images confirm. One of the lander’s three feet can be seen in the foreground. The image is a two-image mosaic. Credit: ESA|
Images released today by the European Space Agency confirm that, for the first time in human history, a spacecraft launched from Earth has landed and survived on a moving comet.
Yesterday, ESA’s Rosetta mission soft-landed its Philae probe on a comet after a seven-hour descent to the surface of Comet 67P/Churyumov–Gerasimenko. A signal confirmed the successful touchdown arrived on Earth at 11:03 a.m. Eastern Standard Time.
But the landing faced some last-minute technical difficulties. Just before the lander separation from Rosetta, a problem was detected with the small thruster on top that was designed to counteract the recoil of the harpoons to push the lander down onto the surface. However, ESA Flight Directors later learned that the harpoons did not fire at landing. It is theorized from data that the lander, without the assistance of the harpoons or thruster, may have made bounced on the comet before coming to a final rest.
The Rosetta spacecraft was launched over a decade ago from Europe’s spaceport in Kourou, French Guiana. During this long voyage, Rosetta had to make three gravitational sling shot maneuvers around the Earth and one around Mars to gain enough speed to catch up with Comet 67P/ Churyumov-Gerasimenko.
Rosetta neared the icy comet on August 6, 2014. After several months of maneuvering the spacecraft into a precise orbit around the comet, Rosetta launched its Philae probe yesterday at 4:03 a.m. Eastern Standard Time (09:03 GMT).
Philae will later focus on the composition and structure of the comet nucleus material. It will also drill more than 20 centimeters into the subsurface to collect samples for inspection by the lander’s onboard laboratory.
Rosetta is the first mission ever to orbit a comet’s nucleus and soft-land a probe on its surface. Rosetta will also be the first spacecraft to fly alongside a comet as it heads towards the inner Solar System, observing how a frozen comet is transformed by the warmth of the Sun. By studying the nature of the comet’s dust and gas, scientists hope that the Rosetta mission will help them understand more about the role of comets in the evolution of the Solar System.