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The Fragment R Collision: W. M. Keck Telescope Observations of SL9

Graham, James R. and de Pater, Imke and Jernigan, J. Garrett and Liu, Michael C. and Brown, Michael E. (1995) The Fragment R Collision: W. M. Keck Telescope Observations of SL9. Science, 267 (5202). pp. 1320-1323. ISSN 0036-8075.

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The W. M. Keck telescope was used to observe the impact of comet Shoemaker-Levy 9 (SL9) fragment R at a wavelength of 2.3 micrometers on 21 July 1994. The data showed three outbursts. The first flash lasted about 40 seconds and was followed 1 minute after its peak by a second flash that lasted about 3 minutes. A third, longer lasting flare began 6 minutes after the first flash and lasted for 10 minutes. At its maximum brightness, the flare outshone Jupiter. The two short flashes are probably associated with the initial meteor trail and the subsequent fireball, respectively. The bright flare occurred when the impact site rotated into view. These data show that the explosion ejected material at least 1300 kilometers above the visible cloud tops. The luminosity of the impact site during the long bright flare was probably maintained by the release of gravitational potential energy, as this material fell back onto the lower atmosphere.

Item Type:Article
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URLURL TypeDescription
de Pater, Imke0000-0002-4278-3168
Liu, Michael C.0000-0003-2232-7664
Brown, Michael E.0000-0002-8255-0545
Additional Information:© 1995 American Association for the Advancement of Science. We acknowledge the invaluable assistance of the entire Keck Observatory staff and especially thank J. Aycock, A. Conrad, P. Gillingham, W. Harrison, and W. Lupton. These observations were made possible by special observing software written by D. Vezie. K. Zahnle provided many ideas and much inspiration. This work was supported by grants from NASA, NSF, and the Packard Foundation.
Group:UNSPECIFIED, Division of Geological and Planetary Sciences
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David and Lucile Packard FoundationUNSPECIFIED
Issue or Number:5202
Record Number:CaltechAUTHORS:20121003-113205572
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Official Citation:The Fragment R Collision: W. M. Keck Telescope Observations of SL9 James R. Graham, Imke de Pater, J. Garrett Jernigan, Michael C. Liu and Michael E. Brown Science , New Series, Vol. 267, No. 5202 (Mar. 3, 1995), pp. 1320-1323
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34667
Deposited By: Ruth Sustaita
Deposited On:03 Oct 2012 20:18
Last Modified:09 Mar 2020 13:19

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