For those who weren’t paying attention, the EPOXI mission formerly known as Deep Impact successfully completed a very close fly-by of comet Hartley 2 yesterday. Since this happened so recently, no analysis has yet been completed of the data, but a gallery of raw unprocessed images can be browsed here.
From now till the end of the month, EPOXI will take up station monitoring outbursts from Hartley 2.
The original Deep Impact mission was launched in 2005, to study comet Tempel 1. On July 4 that year, an impactor was launched at high speed to collide with the comet, so that the resulting plume of gas and debris could be analysed. That mission was completed successfully.
On 1 November, 2007, mission controllers sent instructions to Deep Impact, instructing it to wake up and begin its new mission (EPOXI) maneuvering for a rendezvous with Comet Hartley 2. The goal was to study Hartley 2 and compare it with the four previous comets to be visited by spacecraft.
The core of Hartley 2, shown left, is a little over 2km in length, and the comet has an orbital period just above six years.
Okay, so it seems I spoke to soon: Emily Lakdawalla offers some analysis on the Planetary Society blog here: http://www.planetary.org/blog/article/00002757/. Also, some nicely enlarged high resolution images of the comet. Excellent!