EPOXI / Deep Impact
The Deep Impact and EPOXI missions using the Deep Impact spacecraft built by Ball Aerospace have provided scientists with extremely valuable data on the nature of comets.
On November 4, 2010 at 10 a.m. EDT, the spacecraft approached Comet Hartley 2 at a distance of about 700 kilometers (434 miles). EPOXI was the second mission to use the Deep Impact vehicle built for the 2005 mission that collided with deep-space comet Tempel 1 and excavated material from the nucleus of the comet on the Fourth of July, 2005.
The observation was the fifth time that a comet has been imaged that close, and the first time in history that two comets have been imaged with the same instruments and same spatial resolution.
Using its onboard instruments, Deep Impact observed the nucleus of comet Tempel 1 giving scientists an unprecedented view of the characteristics of comets and the pristine materials inside.
Ball Aerospace was the mission prime contractor for Deep Impact with responsibility for the two-part spacecraft: the Impactor spacecraft and Flyby spacecraft; and three high resolution cameras; algorithm development; environmental testing; and launch and mission support.
Many Ball Aerospace-built instruments were also involved in recording the Deep Impact collision. Three of NASA’s Great Observatories – Hubble, Spitzer and Chandra – were tasked for the event. Ball Aerospace played a significant role in all of these observatories.
Collision in Space
The two-part spacecraft launched together in January 12, 2005 and separated 24 hours before reaching its target. The Impactor separated from the Flyby spacecraft and autonomously positioned itself directly in front of the encroaching Tempel 1 comet.
With closing speeds of 23,000 mph, the Impactor’s active guidance system steered it to impact on a sunlit portion of the comet’s surface. As it closed in on Tempel 1, the Impactor’s camera relayed close-up images of the comet’s surface to the Flyby spacecraft for downlink to Earth. Meanwhile, the Flyby spacecraft used its two instruments to image the impact and then continued to photograph the comet as it followed its orbital path around the Sun. The primary science data was returned to Earth in near real-time, and all data was returned to Earth within one day of the encounter.