This movie made from images obtained by NASA's EPOXI mission spacecraft shows an active end of the nucleus of comet Hartley 2. Icy particles spew from the surface. The specks move as the movie toggles back and forth. Most of these particles are traveling with the nucleus. They are fluffy "snowballs" about 3 centimeters to 30 centimeters (1 inch to 1 foot) across.
The images for the movie were obtained by the Medium Resolution Imager on Nov. 4, 2010, the day the EPOXI mission spacecraft made its closest approach to the comet.NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the EPOXI mission for NASA's Science Mission Directorate, Washington. The University of Maryland, College Park, is home to the mission's principal investigator, Michael A'Hearn. The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.