The power of the SSI for imaging Jupiter's atmosphere is the combination of spatial resolution and spectral coverage. At 30 km/pixel, the SSI is able to image features in the clouds whose horizontal scale is comparable to the pressure scale height. On Earth, such features are associated with deep moist convection and with certain kinds of waves. The typical atmospheric sequence uses four filters: 410 nm (violet), 727 nm (weak methane absorption), 756 nm (nearby continuum), 889 nm (strong methane absorption). At 889 nm, clouds deeper than several hundred mbar are invisible. At 727 nm, clouds deeper than a few bars are invisible. The sequences span 11.5 hours (two jovian rotations), and are designed to track features across the disk during a jovian day. They include an image midway between the terminator and the limb (S1), an image about 9 hours later near the terminator (S2), an image 10 hours after S1 midway between the terminator and the limb (S3), and an image 11.5 after S1 close to the limb. Information is gathered about relative cloud heights and cloud motions. In the vicinity of the Great Red Spot the SSI has detected optically thick, high clouds suggestive of deep moist convection, high-altitude hazes over the Red Spot and elsewhere, nearly cloud-free areas near the high thick clouds, mesoscale waves similar to those seen by Voyager but not aligned with the ambient flow, and small-scale convective bands and spots that change appreciably over a 70 minute period.
AAS/Division for Planetary Sciences Meeting Abstracts #28
- Pub Date:
- September 1996