Why did NASA send an 820-pound probe into the path of a comet?
Comets abound in our solar system. But despite years of observations using ground and space-based telescopes, scientists have speculated on this basic question: Could material buried deep within a comet’s interior have seeded life on our planet? To find an answer, on July 4, 2005, NASA crashed a washing machine-sized probe into a comet the size of Manhattan. The probe was released from NASA’s Deep Impact spacecraft, which captured images of comet Tempel 1 before, during and after the collision. The impact produced a dramatic spray of ice and dust that burst from a newly formed crater. Analysis of the images revealed that comets harbor essential and ancient ingredients of life, including organic material that may have been delivered to Earth billions of years ago. Interior ices and substances in the comet’s core were also preserved, suggesting that they are protected from the sun’s heat. Watch the videos to see how the event unfolded.