[Previous] | [Session 31P] | [Next]
W. B. Colwell, S. A. Stern (SwRI), M. F. A'Hearn (U. Maryland), M. C. Festou, J. Wm. Parker, D. C. Slater, P. M. Tamblyn (SwRI), F. Vilas (JSC), P. R. Weissman (JPL)
In August 1997 we flew the Southwest Ultraviolet Imaging System (SWUIS) aboard the Space Shuttle (STS-85) to observe comet C/1995 O1 (Hale-Bopp) in a variety of visible and ultraviolet bandpasses (http://www.boulder.swri.edu/swuis/). SWUIS is a versatile low-cost UV/Visible imaging instrument designed to observe comets, planetary atmospheres, and objects of astrophysical interest through the UV transmissive window on the Shuttle cabin mid-deck. SWUIS consists of an 18 cm aperature Maksutov-Cassegrain telescope, and a Xybion image-intensified CCD camera sensitive from 2200 Å\ to 8500 Å. The telescope focal length can be varied between 105 and 257 cm for a field of view range of 0.2\circ to 0.6\circ full cone. The 30 Hz frame rate provides high temporal resolution and stabilization against Shuttle jitter.
The STS-85 SWUIS observations of C/Hale-Bopp occurred during the period 9-14 August 1997 when the comet was at a heliocentric distance of 2.3 A.U. when HST observations were not possible (they resumed in September 1997). The SWUIS dataset is the first high resolution UV time-lapse imagery of a comet, providing an opportunity to examine C/Hale-Bopp for morphological changes on time scales of minutes, hours, and days (six consecutive days of observations). These are the only wide field UV images of C/Hale-Bopp.
We have co-added the >430,000 C/Hale-Bopp images (nine hours of data taken during nine orbits) to produce a dataset of half-minute exposure images. Calibration was performed using field stars. We present our data for five bandpasses: broadband continuum, C2, CN, OH, and broadband UV continuum; and discuss our preliminary results on the comet morphology and H2O production rates.
If you would like more information about this abstract, please follow the link to http://www.boulder.swri.edu/swuis/. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.