A'Hearn MF, Belton MJS, Delamere WA, Kissel J, Klaasen KP, McFadden LA, Meech KJ, Melosh HJ, Schultz PH, Sunshine JM, Thomas PC, Veverka J, Yeomans DK, Baca MW, Busko I, Crockett CJ, Collins SM, Desnoyer M, Eberhardy CA, Ernst CM, Farnham TL, Feaga L, Groussin O, Hampton D, Ipatov SI, Li JY, Lindler D, Lisse CM, Mastrodemos N, Owen WM, Richardson JE, Wellnitz DD, White RL. Deep Impact: Excavating Comet Tempel 1.
Science 2005;
310:258-64. [PMID:
16150978 DOI:
10.1126/science.1118923]
[Citation(s) in RCA: 640] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Deep Impact collided with comet Tempel 1, excavating a crater controlled by gravity. The comet's outer layer is composed of 1- to 100-micrometer fine particles with negligible strength (<65 pascals). Local gravitational field and average nucleus density (600 kilograms per cubic meter) are estimated from ejecta fallback. Initial ejecta were hot (>1000 kelvins). A large increase in organic material occurred during and after the event, with smaller changes in carbon dioxide relative to water. On approach, the spacecraft observed frequent natural outbursts, a mean radius of 3.0 +/- 0.1 kilometers, smooth and rough terrain, scarps, and impact craters. A thermal map indicates a surface in equilibrium with sunlight.
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