diff --git a/csst/msc/calib_pos.py b/csst/msc/calib_pos.py
index f9014a6b42fd656fb4ac4067dc6f4396c46bafb8..9daa3ce5bb2c9a7bc1396b27b3e3734d34c89e32 100644
--- a/csst/msc/calib_pos.py
+++ b/csst/msc/calib_pos.py
@@ -10,6 +10,9 @@ from astropy import units as u
 from astropy.coordinates import SkyCoord
 from astropy.io import fits
 from astropy.wcs import WCS
+from astropy.time import Time
+from astropy.table import Table
+
 
 from .. import PACKAGE_PATH
 from ..core.processor import CsstProcessor