HST imaging of atmospheric phenomena created by the impact of comet Shoemaker-Levy 9

Science

Volumn 267, Issue 5202, 1995, Pages 1288-1296

  Hammel, H B ^a   Beebe, R F ^b   Ingersoll, A P ^c   Orton, G S ^d   Mills, J R ^a   Simon, A A ^b   Chodas, P ^d   Clarke, J T ^e   De Jong, E ^d   Dowling, T E ^a   Harrington, J ^a   Huber, L F ^b   Karkoschka, E ^f   Santori, C M ^a   Toigo, A ^c   Yeomans, D ^d   West, R A ^d  

^a MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

^b NEW MEXICO STATE UNIVERSITY   (United States)

^c CALIFORNIA INSTITUTE OF TECHNOLOGY   (United States)

^d CALIFORNIA INSTITUTE OF TECHNOLOGY   (United States)

^e UNIVERSITY OF MICHIGAN   (United States)

^f UNIVERSITY OF ARIZONA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ARTICLE; ASTRONOMY; ATMOSPHERE; MICROCLIMATE;

ATMOSPHERE; EXTRATERRESTRIAL ENVIRONMENT; JUPITER; SOLAR SYSTEM; SUPPORT, U.S. GOV'T, NON-P.H.S.;

EID: 0029633946     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.7871425     Document Type: Article

References (41)

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7. We used the WF3 detector of the Wide Field and Planetary Camera 2 for full-disk images; its 0.09953-arc sec pixels (36) corresponded to about 375 km at the sub-spacecraft point on Jupiter. For the higher resolution PC1 detector, the 0.0455-arc sec pixels (36) subtended about 170 km at the sub-spacecraft point. Significant vignetting in the 889-nm methaneband filter determined the image position in the PC images (7). Rather than repoint the telescope several times in each orbit, we elected to retain the 889-nm pointing to maximize the number of images in each orbit. This constrained us to image only the southern half of Jupiter in PC sequences.
8. C. J. Burrows, Ed., Wide Field and Planetary Camera 2 Instrument Handbook (STScl publication, Baltimore, MD, May 1994).
9. For those impacts where we detected waves, we used the center of the wave to identify the latitude and longitude of the impact site. We also looked for a central impact (that is, we looked for ejecta and used the material's position to estimate the impact location) and then used a circle of 3 or 5 pixels to define a center in this region. In most cases, we examined "before," "after," and later images of the site to make sure we had the best location estimate. We inferred impact times from the difference between predicted and inferred longitudes.
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22. To find the plume heights, we first measured the x and y positions of the plume top and of the center of Jupiter (22). We then computed the distance from the plume top to the planet center and subtracted the distance from the planet center to the point on the limb below the impact. Finally, we added the vertical distance from the 100-mbar level of the impact site to the Earth line-of-sight for the longitude and time of the impact (for times, we used our estimates from Table 2). This rough calculation Is good to within the errors of our ability to define the planet center and plume top.
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27. The algorithm was developed by T. Dowling and C. Santori based on an outline from H. Goldstein, Classical Mechanics (Addison-Westey, Reading, MA, ed. 2, 1980), pp.40-41.
28. -1.
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32. During the Voyager era, there were 13 ovals separated by about 25° longitude on average, with the maximum separation being 61°. If one assumed a missing oval, that implied a wave pattern with n = 14. The HST data show only seven ovals with longitudinal spacing ranging from 110° to 28°, with about 50° being most common. The eastward drift rate of the features has remained constant at about 0.6° per day.
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40. P. W. Chodas and D. K. Yeomans, personal communication.
41. We gratefully acknowledge the staff and management at the Space Telescope Science Institute (STScl) for their fortitude during these unusually challenging observations; we note in particular the assistance of our Comet Science Team colleagues H. Weaver, M. McGrath, and K. Noll, and the heroic efforts of A. Storrs during planning and execution of the observations. We thank J. Trauger and members of the WFPC2 Team for the marvelous instrument, and we also thank our anonymous referees for insightful comments on the manuscript. H.B.H. thanks C. Barnet and L. Gesner for support with software acquisition and development. These observations were made with the NASA-ESA Hubble Space Telescope, with support provided through grant G0-5624.08-93A from STScl, which is operated by the Association of Universities for Research in Astronomy under NASA contract NAS5-26555.