Mid-Infrared Observations during the Deep Impact
Subaru’s COMICS (Cooled Mid-Infrared Camera and Spectrograph) captured the moment when a probe from the NASA spacecraft Deep Impact crashed into Comet 9P/Tempel 1. About 1,000 tons or 100 dump-trucks’ amount of material were ejected by the collision. The combined observations from other ground-based telescope show a complex mix of silicates, water, and organic compounds beneath the surface of Comet Tempel 1. These materials are similar to what is seen in another class of comets that originate in a distant swarm of pristine bodies called the Oort cloud. Once thought of as distant relatives, the short-period comet Tempel 1 and long-period Oort Cloud comets turned out to be similar under the surface.