On July 4, NASA's Deep Impact spacecraft will attempt an extraordinarily daring encounter with the comet Tempel-1, now hurtling through space at tens of thousands of miles per hour. This is made even more challenging because the comet's size, shape and other characteristics are not entirely known.
Two of NASA's eyes in the sky, the Spitzer and Hubble Space Telescopes, helped scientists prepare for the comet encounter. From their orbits high above Earth, the telescopes watched Tempel-1 in early 2004. Together they came up with the best estimates of the comet's size, shape, reflectivity and rotation rate. This is important because the Deep Impact's actual mission is just that, IMPACT. The first intentional impact with a comet by an earth-launched spacecraft.
On July 3, as it approaches Tempel-1, the spacecraft will separate into two parts. One part is an "impactor", designed to slam into the comet in order to release a cloud of gas, dust and debris. The second part will become a "flyby observatory" for collecting data and images of the comet, the impact, and scietific data on the chemical composition of this comet.
In addition to the flyby spacecraft images, at least 30 telescopes around the world, including Spitzer, Hubble and the Chandra X-ray Observatory, will be watching the dramatic impact. By analyzing the material blown out of the interior of the comet, this global network of telescopes will assemble a list of the raw ingredients that went into making the planets in our solar system.
The Deep Impact spacecraft was launched on January 12, 2005. Its mission is to study the primordial soup of our solar system, which is sealed away inside comets. This experiment will be the first opportunity to study the crust and the interior of a comet. As the material inside the comet's nucleus is pristine, it will reveal new information on the early phases of the Solar System. It will also provide scientists with new insight on crater physics, and thereby give a better understanding on the crater record on comets and other bodies in the Solar System.
Article comments
1 - Bennett
Tonight's The Night! The Deep Impact Mission will show up on the west coast around 10:52 Pacific Time, those of us on the east coast can go HERE to watch live pictures from Kitt Peak Observatory, or you can watch NASA TV.
To find the spot where the impact will show up in the night sky, go to this article from Sky And Telescope.
Good luck, I hope you have a chance to check out the first intentional "ramming" of a comet by one of our spacecraft.
Break out the binoculars or a telescope!
Cheers!