FROM NPR: It’s taken 10 years to travel 4 billion miles, but the Rosetta spacecraft has finally placed a lander on a comet. It’s a mission that’s never been attempted before. The landing was a huge scientific milestone, especially since terrain on the 2-mile rubber ducky-shaped comet was much rougher than scientists originally thought. Now that Philae has landed safely, scientists are hoping she will provide critical information about the evolution of our solar system, the origin of water, and the building blocks of life on Earth.

Dr. Emily Rice, a professor of astrophysics at the College of Staten Island and a researcher at the American Museum of Natural History, explains the details of this mission on>