 approximate geographic area of interest and is returned by
the SetRegion set of routines. It has a center latitude/longitude
which uniquely describes a single location on the globe and half an
extent measured in meters, in both the latitude and longitude
directions. This structure is used by the MtkReadData routine to
subset MISR data when reading. Typically this structure does not need
to be accessed directly, but rather just passed to MtkReadData. No
dynamic memory is allocated, so there is nothing to fr