1. XM Status, Priorities and Plans Icy Satellites
C. J. Hansen, A. Hendrix
January 2008

2. Observation Types Primary Mission
ICYMAP - Map uv albedo at high resolution; scans across satellite
ICYEXO - Detect volatiles by absorption; observe occultation of “bright 19” star
ICYOCC - Chord for satellite location, size; observe occultation of star
ICYLON - Sample uv albedo as f(phase, longitude); Sit ‘n stare
ICYSTARE - Detect volatiles as emission feature; long sit ‘n stare integration
ICYATM - Detect oxygen in region around Enceladus; mini system scan
New
ICYECL - Look for post-eclipse brightening as evidence of volatiles condensing during eclipse; sit ‘n stare
ICYLIMB (new) - Look for volatiles near limb; slow scan onto limb
ICYPLU - long integration to look for Enceladus’ plume (rider on ISS)
Notes: Observation types are in priority order. Ok to give up ICYATMs and ICYOCCs. Fight for ICYEXOs.
Status: All non-targeted flyby CIMS entries are in, Observation Descriptions have been populated with IEB settings desired

3. ICYMAP Example
Will get maps of Enceladus, Dione, and Rhea in the XM

4. Enceladus Observation Suite
System scans show variable atomic oxygen in Saturn’s system
Localized scans across Enceladus give higher resolution picture of the distribution of oxygen
Link to highest resolution to characterize the eruptive state
Execute routinely to monitor Enceladus’ activity remotely

5. Enceladus Flyby Timelines

6. Solar Occultation Rev 131
We will observe an occultation of the sun on Rev 131
New results are in the EUV, which gives us access to a different wavelength range than the FUV
The big scientific payoff is the chance to definitively detect / measure nitrogen in the plume - important for models of chemistry-driven dynamics in the interior