On Wednesday, Nov. 12, the European Space Agency's Rosetta mission successfully landed on the surface of comet 67P/Churyumov-Gerasimenko. Descending at a speed of about 2 mph (3.2 kilometers per hour) the lander, called "Philae," first touched down and its signal was received at 8:03 a.m. PST (11:03 a.m. EST).
Partially due to anchoring harpoons not firing, and the comet's low gravity (a hundred-thousand times less than that of Earth), Philae bounced off the surface and flew up to about six-tenths of a mile (1 kilometer) both above the comet's surface as well as downrange. At 9:53 a.m. PST (12:53 p.m. EST), almost two hours after first contact, Philae again touched down. A second, more modest bounce resulted, again sending it airborne. Philae's third contact with the comet's nucleus was the charm. At 10 a.m. PST (1 p.m. EST), the Rosetta mission's Philae lander became the first spacecraft to soft-land on a comet.
After more than a decade traveling through space, a robotic lander built by the European Space Agency has made the first-ever soft landing of a spacecraft on a comet.
Mission controllers at ESA's mission operations center in Darmstadt, Germany, received a signal confirming that the Philae lander had touched down on comet 67P/Churyumov-Gerasimenko on Wednesday, Nov. 12, just after 8 a.m. PST/11 a.m. EST.
This image of comet 67P/Churyumov-Gerasimenko was acquired by the Philae lander of the European Space Agency's Rosetta mission during Philae's descent toward the comet on Nov. 12, 2014. Philae's ROLIS (ROsetta Lander Imaging System) took the image at 14:38:41 UTC (6:38:41 a.m., PST) at a distance of approximately two miles (three kilometers) from the surface. The landing site is imaged with a resolution of about 10 feet (three meters) per pixel.
A statement about Rosetta from John Grunsfeld, astronaut and associate administrator for NASA's Science Mission Directorate, is online at:
The lander is expected to send images from its landing site, named Agilkia. These will be the first images ever taken from a comet's surface. Philae will also drill into the surface to study the composition, and witness close up how a comet changes as its exposure to the sun varies. With its primary battery, Philae will remain active on the surface for about two-and-a-half days. Philae's mothership, the Rosetta spacecraft, will remain in orbit around the comet through 2015. The orbiter will continue detailed studies as the comet approaches the sun and then moves away.
In addition to their well-deserved reputation as beautiful cosmic objects, comets hold vital clues about our solar system's history. They are considered primitive building blocks of the solar system that are literally frozen in time. Comets may have played a part in "seeding" Earth with water and, possibly, the basic ingredients for life.
NASA provided three of the 16 instruments on board the Rosetta orbiter. The NASA instruments are: the Microwave Instrument for Rosetta Orbiter (MIRO); Alice, an ultraviolet spectrometer; and the Ion and Electron Sensor (IES), which is part of a suite of five instruments. For more information on the U.S. instruments aboard Rosetta, visit:
