NASA has released the mission description document for tomorrow morning's Enceladus-1 flyby. None was released for the flyby last month since technically it was a non-targeted flyby despite having a "targeted" flyby distance. The document contains information on Enceladus, Enceladus science questions, goals for this flyby, graphics showing planned observations, and timelines for data acquisition and playback. Among the highlights:
- The mass determination from the Rev 3 encounter found that the internal rock-ice ratio is higher than previously estimated
- No ammonia has been detected at Enceladus in infrared spectra
- CIRS measurements on the day and night sides of Enceladus will map surface temperatures to determine thermal inertia. If active sources are present, CIRS will determine their spatial distribution and energy output. CIRS will search for spectral signatures on the surface and in plumes (if present) to determine composition.
- ISS will perform meter-scale resolution imaging to determine geological structures and investigate the satellite's history.
- RADAR scatterometry of the surface will determine roughness at cm scales. Radiometry will probe the energy balance of Enceladus.
- UVIS will make UV maps of the surface of Enceladus to understand surface composition and will look for emission features suggestive of a tenuous atmosphere.
- VIMS will investigate the identification of minerals and other materials on the surface, and will perform mapping of the abundance and grain sizes of surficial materials.
- MAPS instruments will examine the particle environment at ~500 km from the surface to determine the nature of material coming off the surface and the relationship between the satellite and the E-ring, and the satellite and its immediate magnetospheric particle environment.
- Data from the inbound, "dayside" part of the flyby will be played back tomorrow morning, between 9:30 and 11:00 am MST. Data from the outbound, "nightside" part of the flyby and from the Tethys non-targeted flyby will be played back Wednesday evening between 7:23 and 11:00 pm MST.