Recycled NASA Spacecraft to Fly by Earth, Comet
This is an artist's rendition of the Deep Impact flyby spacecraft releasing its impactor, 24 hours before the impact event in July 2005. Pictured from left to right are comet Tempel 1, the impactor, and the flyby spacecraft. The impactor is a 370-kilogram mass with an onboard guidance system. The flyby spacecraft includes a solar panel (right), a high-gain antenna (top), a debris shield (left, background), and science instruments for high and medium resolution imaging, infrared spectroscopy, and optical navigation (yellow box and cylinder, lower left). The fly spacecraft is about 3.2 meters long, 1.7 meters wide, and 2.3 meters high. The launch payload has a mass of 1020 kilograms.
Credit: NASA/JPL

A recycled NASA spacecraft that has already bombed one comet is headed for another one, after a slight detour by Earth that required a tricky engine maneuver to put it on track for both flybys.

The Epoxi spacecraft, which was originally built as the mother ship for NASA's Deep Impact mission mother ship, fired its engines on May 28 for 11.3 seconds to fine-tune its planned June 27 flyby past the Earth and trip to visit the comet Hartley 2 in November.

"While it was a small burn, it was a big step in getting us to Hartley 2," said Tim Larson, Epoxi project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "Humanity's fifth close-up view of a comet is less than five months away."

The maneuver sets the stage for a planned Nov. 4 swing by the comet Hartley 2, though Epoxi will just observe that icy wanderer and not let loose an impactor probe to crash into it like the original Deep Impact mission did to the comet Tempel 1 in 2005.

That earlier Deep Impact mission intentionally crashed a probe into Tempel 1 to determine the comet's composition. [Photos of the comet crash.]

Epoxi's recent engine burn changed the spacecraft's velocity by a mere 0.1 meters per second (less than a quarter mile per hour). But that was all the mission navigators needed to take advantage of Earth's gravity to get a speed boost for Epoxi's trip to Hartley 2.

Epoxi is an extended, unmanned mission of the Deep Impact space probe. Its name is derived from its dual science investigations ? the Deep Impact Extended Investigations (DIXI) and the Extrasolar Planet Observation and Characterization (EPOCh).

The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., located in Boulder Colo. JPL manages Epoxi for NASA's Science Mission Directorate in Washington, D.C. The University of Maryland is the Principal Investigator institution.