Deep Impact Flyby took a look back at the devastation it wrought on Comet Tempel 1 and snapped a spectacular image of impact ejecta streaming out into space in a column that has grown much larger in dimension than the comet nucleus itself. While images and other data continues to stream to the Earth from Flyby, scientists are examining the data already received, including temperature readings of the nucleus before impact and spectral readings that will provide the composition of the comet.
At this morning’s Post-Impact Briefing held at NASA’s Jet Propulsion Laboratory in Pasadena, California, USA, scientists displayed new images of the comet and preliminary scientific results. Principal Investigator Dr. Mike A’Hearn noted that Comet Tempel 1 was shaped more like “a loaf of bread or a muffin” than the various fruits people have previously suggested in analogy. Dr. A’Hearn said that this loaf has a lot of topographic relief, craters that may have been formed by natural impacts, and intriguing bright spots. Scientists have spotted evidence for layering of material on the comet and regions of smooth areas that are unexplained.
Dr. Pete Schultz, the Co-Investigator from Brown University, described the impact itself and the search for the resulting crater. He presented an animation created from images taken by Flyby of the event. There was a brief incandescent flash of light as volatile gases were vaporized when Impactor first made contact with the cometary surface, followed by a split second pause before a huge explosion of material erupted from the rapidly-forming crater. This plume of ejecta cast a growing shadow on the surface. A cloud of dust kicked up by the collapsing crater wall was also spotted in images. The new crater was obscured by dust and gas from the eruption, but scientists will try to enhance likely images of the region in search of the crater. They do not expect to have preliminary results until later this week.
Flyby “is in great shape,” according to Rick Grammier, Deep Impact Project Manager at JPL. Flyby will continue to capture images and other data about Tempel 1. When its primary mission ends and all the data has been returned to the Earth, the spacecraft will enter a sun-safe mode with only critical systems functioning until a potential extended or different mission has been chosen and funded.
Earlier figures for traffic to the Deep Impact website indicate a billion hits, far more than the traffic the Cassini-Huygens and Mars Exploration Rovers websites experienced at their peak, combined. Planetary science mission sites often become the new record-holders for all-time traffic numbers in the first few days of their mission, beginning with the 100 million hits over three days seen by the NASA’s Mars Pathfinder Rover site in 1997. While website hit statistics do not indicate the exact number of individual visitors, they do indicate the popularity of a site.