UVIS Goals for CSM R. West

Solar and Stellar Occultations Occultations provide N2 density profiles, compositional information on some hydrocarbons and haze structure in the region 300-3000 km altitude (in the ‘ignorosphere’ between 400 and 900 km UVIS provides the only information Detailed vertical profiles but point locations in lat, lon. EUV (solar) for N2; FUV (star occs) for hydrocarbons and haze Advocacy for VIMS solar occs – hydrocarbons, CO, and haze down to the surface

Criteria Need a distribution in latitude, with attention to high latitudes where the winter polar vortex is expected to be present in the south Need time coverage to assess seasonal and solar variations Need approximately radial occs For stellar occs, slower is better

Stellar Occ Opportunities

Solar Occ Opportunities

Specifics ‘Penciled-in’ opportunities T78 Low/mid latitude, early opportunity, CIRS and CAPS get most of the time T103 High latitude in both hemispheres, good stellar occ T116 High priority stellar occs, and high priority solar occs for VIMS T118 joint with INMS Star occs outside of +- 2 hr. on T101, 105, 116