SPACE -- November 4, 2010 at 4:08 PM ET
NASA Snaps Photos of Comet Hartley 2
A NASA fly-by mission snapped and then beamed back pictures of a small peanut shaped-comet Thursday, marking only the fifth time that a comet's core has been viewed so close. The spacecraft, formerly known as Deep Impact, but renamed EPOXI, flew within 435 miles of Comet Hartley 2 just after 10 am, capturing a series of high-resolution close-ups.
What we know about Comet Hartley 2: It's .93 miles across -- tiny for a comet - but spews more gas and dust than other, bigger comets. It was first discovered by astronomer Malcolm Hartley in New South Wales Australia in1986, as a smudge on a photographic plate. And it was created about 4.2 to 4.5 billion years ago, beyond the planet Neptune.
Comets are small icy masses of dust and gas and believed to contain ancient materials from the formation of the solar system. Scientists study them to better understand their composition, along with how the solar system formed.
Michael A'Hearn, the mission's principal investigator, says they plan to plumb the images and spectra taken by EPOXI for information on the comet's structure and chemical composition. "We want to separate all the aspects of the comet that we can see into two groups -- aspects that reflect evolution and modern processing... and aspects that reflect the initial formation conditions," A'Hearn says. "The latter, of course, is what we really want."
This post was updated at 3:15 p.m. ET on Nov. 5