The late night comedians won’t be able to make fun when Deep Impact crashes into a comet: it’s supposed to do that.
July 4th should be the day when NASA’s Deep Impact mission reaches its endpoint at comet Tempel 1. The Impactor probe will hit the comet at a speed of about 23,000 miles per hour while the Deep Impact spacecraft watches.
The copper fortified probe should hit the Manhattan Island-sized ball of ice at 1:52 AM EDT on July 4th. Ground and space observatories will watch the collision. The mission specialists will have to hope for a smooth deployment of the impactor into the comet’s path.
“We are really threading the needle with this one,” said Rick Grammier, Deep Impact project manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
“In our quest of a great scientific payoff, we are attempting something never done before at speeds and distances that are truly out of this world.”
But when they do thread that needle, the impactor will be the one guiding the thread. After its deployment and guidance from Earth for 22 hours, the autonomous navigation system will take over for the last two hours of the mission. The comet and the spacecraft are about 83 million miles from Earth.
“The autonav is like having a little astronaut on board,” Grammier said. “It has to navigate and fire thrusters three times to steer the wine cask-sized impactor into the mountain-sized comet nucleus closing at 23,000 miles per hour.”
NASA scientists estimate the resultant collision will make a crater sized between a large house and a football stadium. That will displace dust and ice to reveal the material beneath the comet’s surface. Meanwhile, Deep Impact will have about 13 minutes to photograph and transmit images and data from the area, before being hit by pieces of the comet.
Scientists believe the material within the comet will give clues about the formation of the solar system. The Deep Impact collision poses no threat to Earth. “In the world of science, this is the astronomical equivalent of a 767 airliner running into a mosquito,” said Dr. Don Yeomans, a Deep Impact mission scientist at JPL. “The impact simply will not appreciably modify the comet’s orbital path.”
David Utter is a staff writer for murdok covering technology and business. Email him here.
