European Space Agency/Rosetta
The Rosetta spacecraft's farewell photo of the Philae lander making its descent to the surface of Comet 67P.
It was a jittery night for scientists at the European Space Agency: The international space organization had launched the Rosetta
spacecraft in March 2004, and after a decade in space that took the craft approximately 500 million miles from the sun, scientists at Rosetta's mission control center were about to plant Rosetta's lander, Philae, on a comet just 2.5 miles in diameter.
At approximately 8 a.m. Pacific Time, Philae reached the surface of the comet, 67P/Churnyumov-Gerasimenko, after a seven-hour drop. The comet is 300 million miles from Earth, and this is the first time in history that humans have landed a craft on a comet.
While Rosetta has been able to make invaluable observations about Comet 67P's attributes, Philae is equipped to make observations about the comet's physical and molecular composition. Rosetta will continue to follow the comet while Philae broadcasts its findings from the surface.
"It's a look at the basic building blocks of our solar system, the ancient materials from which life emerged. It's like doing archaeology, but instead of going back 1,000 years, we can go back 4.6 billion," Kathrin Altwegg of the University of Bern in Switzerland, one of Rosetta's project leads, told The Washington Post