Deep Impact: excavating comet Tempel 1.

M F A'Hearn; M J S Belton; W A Delamere; J Kissel; K P Klaasen; L A McFadden; K J Meech; H J Melosh; P H Schultz; J M Sunshine; P C Thomas; J Veverka; D K Yeomans; M W Baca; I Busko; C J Crockett; S M Collins; M Desnoyer; C A Eberhardy; C M Ernst; T L Farnham; L Feaga; O Groussin; D Hampton; S I Ipatov; J-Y Li; D Lindler; C M Lisse; N Mastrodemos; W M Owen; J E Richardson; D D Wellnitz; R L White

doi:10.1126/science.1118923

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PubMed · 16150978

Deep Impact: excavating comet Tempel 1.

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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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Jupiter Meteoroids Organic Chemicals Spectrum Analysis Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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M F A'Hearn, M J S Belton, W A Delamere, J Kissel, K P Klaasen, L A McFadden, K J Meech, H J Melosh, P H Schultz, J M Sunshine, P C Thomas, J Veverka, D K Yeomans, M W Baca, I Busko, C J Crockett, S M Collins, M Desnoyer, C A Eberhardy, C M Ernst, T L Farnham, L Feaga, O Groussin, D Hampton, S I Ipatov, J-Y Li, D Lindler, C M Lisse, N Mastrodemos, W M Owen, J E Richardson, D D Wellnitz, R L White. 2005-09-08. Deep Impact: excavating comet Tempel 1.. https://doi.org/10.1126/science.1118923

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