Posted on 06/28/2005 4:43:23 PM PDT by neverdem
WASHINGTON, June 27 - A two-stage spacecraft called Deep Impact is about to make an ambitious attempt to dissect a comet by slamming into it and blowing some of its innards into space for all to see.
Launched from Florida on Jan. 12, NASA's Deep Impact is nearing the end of a finely calibrated 268-million-mile journey that puts comet Tempel 1 within its sights.
An 820-pound copper-core "impactor" is to smash into the comet's nucleus at 23,000 miles an hour in the early hours of July 4, an unprecedented event that will, if all goes well, be witnessed by its companion craft and numerous observatories in space and on Earth. Because of the distance and timing of the encounter, experts said that only Earth observers in the Pacific area using telescopes were likely to see the comet and any evidence of the impact.
Rick Grammier, the mission's project manager at the Jet Propulsion Laboratory in Pasadena, Calif., said the final part of the encounter 83 million miles away was so intricate and so fast that the twin ships would have to handle these maneuvers on their own without help from human controllers. "It's a bullet trying to hit a second bullet with a third bullet, in the right place at the right time," he said.
Scientists say the impact, which should occur at about 1:52 a.m. Eastern time, could excavate a crater as large as a sports stadium and send plumes of material from the comet's core far into space, allowing the first view of the pristine inner material that makes up these icy bodies.
Comets are believed to be remnants of the materials that formed the solar system some 4.5 billion years ago. Astronomers believe comets' interiors have undergone little change since then and contain the pristine ice...
(Excerpt) Read more at nytimes.com ...
"Astronomers believe comets' interiors have undergone little change since then and contain the pristine ice, gases, dust and other materials from which the rest of the solar system formed. Understanding comets is a way of understanding how the solar system was born.
"Another reason to study comets is that they, along with rocky asteroids, pose a threat of hitting the Earth and causing cataclysmic damage. Defending against such possibilities requires knowing more about these objects in hopes of deflecting or destroying dangerous ones, experts say."
See comment# 21.
Hats off to NASA!
The best I can do with either my .270 or the .30-06 is about 300 yards.
That "washing-machine" and getting it up there in space cost us 300 million dollars, by the way. And we're going to watch it explode.
I remember scientists' concern years ago with "life" contained within comets and asteroids - perhaps only bacteria, perhaps more, but to arbitrarily slam a projectile into an unknown entity wouldn't have been proper in those days. It's like a boy shooting a cat in the head to "see" what will happen." NASA's justifications are usually scripted long before costly project proposals are submitted to the wounded taxpayer. I'm surprised that a "it's for the kids" reason wasn't tested for public acceptability on this comet game.
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