NASA is all set to launch its £140/$266 million craft Deep Impact next week to probe the nucleus of comet Tempel 1.
If everything works out according to the plan, the Deep Impact - which will begin its six-month journey from Cape Canaveral in Florida on Jan. 12 - will fire an 800lb ‘impactor’ module that will crash into its target (comet Tempel 1) at a speed of 22,800 mph, creating a hole seven storeys deep and as wide as a football pitch in its core, releasing clouds of debris into space.
The mother ship loaded with scientific instruments will then film the collision and analyse contents of the dust. Along with Deep Impact, space telescopes on the Earth such as Hubble, Chandra and Spitzer will also observe the event as the material is blown away.
Michael A’Hearn, professor of Astronomy at the University of Maryland and Deep Impact’s chief scientist said: “We know so little about the structure of cometary nuclei that we need exceptional equipment to ensure that we capture the event. We will be capturing the whole thing on the most powerful camera to fly in deep space.”
While Rick Grammier, Deep Impact project manager at Nasa’s Jet Propulsion Laboratory said: “The six-month journey is relatively short in cosmic terms. From Central Florida to the surface of a comet in six months is almost instant gratification from a deep space mission viewpoint. It is going to be an exciting mission and we can all witness its culmination together as Deep Impact provides the planet with its first man-made celestial fireworks display American Independence Day on July 4.”
When the ‘impactor’ collides with comet Temple 1 it will experience the speeding lump of rock and ice, which is as large as a mountain. The data that scientists gather from the mission, however, could be useful in planning future missions to divert comets that do present a threat. Another aim is to find out whether the interior of the nucleus is very different from its surface.
However, scientists said, there is no danger that collision will divert the comet’s path in any significant way, let alone that it might nudge it into an orbit that could threaten a collision with Earth. “It simply will not appreciably modify the comet’s orbital path, and comet Tempel 1 poses no threat to the Earth now or in the foreseeable future,” they said.
Tempel 1 was discovered in 1867 and orbits the Sun every five and a half years. It often passes through the inner solar system, making it a good target for scientific study.
