[Previous] | [Session 43P] | [Next]
S. G. Gibbard, B Macintosh, C. E. Max, D Gavel (Lawrence Livermore National Lab), I de Pater (University of California, Berkeley)
The atmosphere of Neptune, with a strong internal heat source driving vigorous convection, shows considerable variation over time. Storm features such the the Great Dark Spot observed by Voyager 2 endure for timescales of months or years. Bright features are also seen at infrared wavelengths, perhaps associated with these storms. We present the results of a series of observations of Neptune made from the 10-meter W.M. Keck I Telescope over the period of 1996-1998. Observations were made using speckle imaging with the H-band filter (centered at 1.65 microns) which allows an unprecedented resolution of 0.04 arcseconds (0.02 arcseconds per pixel) across the disk of Neptune. This allows us to observe changes in the location, size, and shape of bright features over timescales of hours, days, months, and years. Rotation rates for the planet at several different latitudes are derived from this data. Use of lower-resolution narrow band images taken on the same nights as the speckle data will allow us to constrain the location and vertical extent of the bright features.