After months of delays in development of its elaborate guidance software system, NASA’s Deep Impact unmanned space probe is launched on a mission to intercept, and fire an impactor into, Comet Tempel 1 half a year later. In order to catch up with the comet, Deep Impact is lofted into orbit by a Delta II rocket, which puts the spacecraft on a precise course at a speed of roughly 64,000mph. Deep Impact will fire the impactor into the comet in July to study the distribution and composition of the debris scattered by the resulting impact.
After months on a precise interception course, NASA’s unmanned Deep Impact space probe meets up with Comet Tempel 1, firing a impactor into the comet’s nucleus to study the distribution and composition of the debris scattered by the resulting impact. The impactor had been released by the flyby spacecraft six days earlier, and transmitted its images and readings to the flyby vehicle, which records them and retransmits them to ground controllers on Earth. The two vehicles’ on-board software tracks the comet so precisely that the impact happens within a second of the anticipated timeline in the mission plan, kicking up enough cometary dust to obscure the view of the crater left on the comet’s nucleus. Following the Tempel 1 mission, the still-intact Deep Impact flyby vehicle is redirected for future missions to other objects in the solar system.
NASA’s Deep Impact probe, already a veteran explorer of comets, turns its camera eye toward Comet ISON, a recently-discovered comet expected to put on a spectacular show even to the naked eye in late 2013. Originally launched in 1995 to study Comet Tempel 1 at close range, Deep Impact has since used its cameras to study other comets passing through the solar system. The distance between Deep Impact and Comet ISON at the time the 36-hour photo sequence is taken is roughly 493 million miles.