| Description: Provides the ordinary longitude coordinate of the origin (oblique latitude = oblique longitude = 0) for the oblique coordinate system used to specify the OBLIQUE_CYLIDRICAL projection used in Cassini BIDR. NOTE that whereas some past PDS products may utilize oblique projections defined solely in terms of the REFERENCE_LATITUDE and REFERENCE_LONGITUDE (i.e., with a third defining angle always set to zero), the Cassini BIDRs require the full generality of three nonzero rotation angles. These angles are represented by the keywords OBLIQUE_PROJ_POLE_LATITUDE, OBLIQUE_PROJ_POLE_LONGITUDE, and OBLIQUE_PROJ_POLE_ROTATION. The values of REFERENCE_LATITUDE and REFERENCE_LONGITUDE are consistent with the latter three angles but do not uniquely define the oblique coordinate system on their own. |