SSB-46: Download from a mirror if fails

CAL/CalibrationCommon/lib/coordinates.py

@@ -8,7 +8,11 @@ from astropy.utils.data import download_file
 from astropy.utils import iers
 from astropy.time import Time
 
-iers.IERS.iers_table = iers.IERS_A.open(download_file(iers.IERS_A_URL, cache=True))
+
+try:
+    iers.IERS.iers_table = iers.IERS_A.open(download_file(iers.IERS_A_URL, cache=True))
+except:
+    iers.IERS.iers_table = iers.IERS_A.open(download_file(iers.IERS_A_URL_MIRROR, cache=True))
 
 
 def mjd_to_astropy_time(mjd_time_seconds) -> Time: