[Previous] | [Session 7P] | [Next]
L. A. Lebofsky (UAZ), D. McCarthy (UAZ), E. K. Hege (UAZ), R. P. Binzel (MIT), J. Drummond (Phillips Lab), M. J. Gaffey (RPI), P. C. Thomas (Cornell), E. Wells (CSC), B. Zellner (GSU)
The near-infrared camera (NICMOS) onboard the Hubble Space Telescope (HST) has imaged the complete surface of asteroid 4 Vesta to map its diverse mineralogy and to investigate more thoroughly the recently discovered major impact basin at the south pole. The extremely high signal-to-noise imaging, broad wavelength coverage (0.95 to 2.22 microns) and distinctive narrow band filters provided by NICMOS allow the first discrimination of the mineralogies of lava flow regions between eucrite, howardite, and diogenite assemblages. The excellent dynamic range of these images allows detection of low contrast features at, and possibly beyond, the diffraction-limited resolution of HST. Identical observations of a solar-type star permit accurate removal of the point spread function. Two methods of image deconvolution (MEM, IBD) have been employed and show excellent agreement. The final global mineralogic map which results from these images will help reveal Vesta's volcanic and impact history.
The author(s) of this abstract have provided an email address for comments about the abstract: lebofsky@lpl.arizona.edu