NASA launched the spacecraft Deep Impact on Wednesday, January 12, 2005 on a mission to Comet Tempel 1. The 820-pound spacecraft will travel 268 million miles, more than 80 million miles from Earth and just beyond the orbit of Mars, to crash into the 9-mile wide comet at a speed of 23,000 miles per hour. The impact will be equivalent to 4.5 tons of TNT exploding. The debris from the comet poses no threat to Earth, neither will the slight change in the comet’s orbital path.
The impact will create a crater in the comet. Its size will depend on the materials in the comet and the comet’s structure. If the comet has been around the sun many times, its structure may be very weak from the loss of gasses and dust as it heats up near the sun. If the comet is relatively new at passing around the sun, it may be a very solid ball of ice. Ice, dust, and other primordial material will be analyzed by the spacecraft. Scientists believe it may tell us more about the comet’s nuclei or core and maybe even the early solar system.
