| Description: The activity_id attribute describes the type of measurement contained in a CRISM EDR or other data product, and provides indication of how the observation is commanded. The format of the value is AC### where AC is a 2-letter designation of the type of measurement made, and ### is a 3-numeral designation of the instrument command macro that was executed to acquire the data. Macro numbers are in the range 0-255. For EDRs, BI is measurement of detector bias, DF is a measurement of background including dark current and thermal background, LP is measurement of a focal plane lamp, SP is measurement of the internal integrating sphere, and SC is measurement of an external scene. TP indicates that the EDR contains any test pattern produced by instrument electronics. T1 through T7 specify the test pattern, test pattern 1 through test pattern 7. UN indicates that the EDR contains data in which housekeeping does not match the commanded instrument configuration. For an RDR, RA indicates that the file contains values in units of radiance (W m^-2 nm^-1 sr^-1). IF indicates that the file contains values in units of I/F, or radiance divided by solar flux scaled for heliocentric distance. AL indicates that the file contains values as estimated Labert albedo, which is I/F corrected for cosine of incidence angle and for atmospheric and thermal effects. SU indicates that the files contains summary parameters, unitless values derived from Lambert albedo. For an RDR or a DDR, DE indicates that the files contains derived values related to observation geometry or independently characterized properties of the scene. |