NOTE: The Cassini ISS and VIMS teams define the TARGET_NAME associated with an observation as the object relative to which the pointing has been defined. The practical implications of this choice are as follows:
(1) The ISS and VIMS teams never
identify the target of an observation as Saturn's rings. Instead, essentially all ring observations are described by TARGET_NAME = SATURN.
(2) For close encounters with satellites, the Cassini spacecraft often uses inertial pointing. When this occurs, the ISS and VIMS teams identify the observation as TARGET_NAME = SKY, rather than specifying the name of the moon being encountered.
The Image Atlas
at the PDS Imaging Node
is built on the index files generated by the teams, and so will return "false negatives" in these situations.
The PDS has identified several ways to work around these potentially misleading identifications.
(1) Within the OPUS
database, maintained by the PDS Rings Node
the "Intended Target Name" is updated for observations of these types. Searches using the "Intended Target Name" within OPUS should yield satisfactory results.
(2) The OPUS
Surface Geometry selector tab lets the user search for any body within the ISS or VIMS fields of view, regardless of whether or not it was identified as the target of the observation.