FUNCTION is_orbit_valid, orbits_in, info=info

   missing_orbit_filename = !CIPS_ROOT + '/calibration_data/missing_orbits/missing_orbits.txt'
;   orbit_template = ASCII_TEMPLATE( missing_orbit_filename )
   missing_orbit_filename_template= !CIPS_ROOT + '/calibration_data/missing_orbits/orbit_template.sav'
;   SAVE, orbit_template, FILENAME = missing_orbit_filename_template

   RESTORE, FILENAME = missing_orbit_filename_template
   missing_orbits = READ_ASCII( missing_orbit_filename, TEMPLATE = orbit_template )
   index = WHERE( missing_orbits.orbit EQ orbits_in )
   IF index[0] NE -1 THEN BEGIN
   	  PRINT, orbits_in, " is a known missing orbit."
      IF KEYWORD_SET( info ) THEN BEGIN
         info = missing_orbits.reason[index]
      ENDIF
      RETURN, 0
   ENDIF ELSE BEGIN
      RETURN, 1
   ENDELSE
END