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Spacecraft Rosetta Deploys Lander on Comet
The European Space Agency spacecraft Rosetta successfully released its lander Philae onto Comet 67P (Churyumov-Gerasimenko) at 11:03 EST, the first landing on a comet in history. The first landing of a spacecraft on an asteroid was performed by NASA’s NEAR Shoemaker in February 2001.
ESA’s German mission control center got word that Philae touched down 28 minutes after it occurred, the fastest communication can travel from its far location.
The operation took place over 300 million miles away at a speed of 40,000 mph. Rosetta’s journey began 10 years ago, and logged over 4 billion miles because it first had to slingshot around Earth three times and then once around Mars to obtain enough speed to catch up to the comet. The comet itself is only 2.5 miles in diameter.
The lander Philae, about the size of a washing machine, was allowed to free-fall onto the low-gravity environment of Comet 67P (several hundred thousand times weaker than Earth*) and secure itself with ice screws and harpoons. Although indicating the harpoons failed, the lander appears to be stable, according to the ESA. The comet’s spin rotation is only once per 12 hours.
Between Philae and Rosetta there will be 21 instruments to collect data that scientists hope will help explain the origins and evolution of the universe. Philae's instruments include devices to measure light, electrical magnetism, and heat. It will also drill eight inches below the surface of the comet to extract samples to be analyzed onboard. Its battery is expected to last 64 hours but is ample enough to collect a wealth of information. After that, solar panels will attempt to provide about an hour of battery life per day.
The comet’s rather eccentric orbit around the sun, at a period of 6-1/2 years, will reach its next perihelion (closest point to the sun) in August of 2015 and expel hundreds of kilograms of material every second (the characteristic tail of a comet). It is thought that this activity along with the rising temperature will cause damage to Philae and even Rosetta. The orbiter will remain alongside the comet for over a year and the lander predicted to be stuck to the comet indefinitely even after its systems have shut down.
© ESA/Getty Images In this February 17, 2014 handout photo illustration provided by the European Space Agency (ESA) the Philae lander is pictured descending onto the 67P/Churyumov-Gerasimenko comet.
* This data appears to be inaccurate. The gravity of Comet 67P is 10-3 m/s2 (one ten-thousandth of Earth's gravity) - 11/13/14