In business, repurposing is all the rage. Take a product or service intended for one purpose and have it do something else.

Even NASA has caught the repurposing bug. The agency took its Deep Impact spacecraft — the one that in 2005 sent an 800-pound probe crashing into comet Tempel 1 to understand better the composition of comets — and gave it a new mission.

Two missions, really. One was to study known extrasolar planets with one of the telescopes on the spacecraft, and the other to fly past a second comet, Boethin, in 2008, and try to characterize it by surveying it with cameras and an infrared spectrometer.

But since what is now called the Epoxi mission was announced, a problem cropped up. Boethin, which is about a mile in diameter and was discovered in 1975, seems to have disappeared. Astronomers cannot locate it and suggest that it may have broken into pieces to small to be seen.

So in addition to repurposing Deep Impact, NASA is retargeting it, too. The agency announced last week that it had approved sending the spacecraft to another small comet, Hartley 2. The spacecraft has already performed a course-correcting rocket burn, and it is now scheduled to pass within about 600 miles of the comet in October 2010.