commit e1e8631583ae26b1ac521afcf9b4f1fd640427fe
Author: Hugo Buddelmeijer <hugo@buddelmeijer.nl>
Date:   Tue Aug 4 09:33:22 2026 +0200

    Set iers auto_download default to False.

diff --git a/astropy/utils/iers/iers.py b/astropy/utils/iers/iers.py
index 0541831366..acaf36826b 100644
--- a/astropy/utils/iers/iers.py
+++ b/astropy/utils/iers/iers.py
@@ -166,13 +166,14 @@ class Conf(_config.ConfigNamespace):
     """
 
     auto_download = _config.ConfigItem(
-        True,
+        False,
         "Enable auto-downloading of the latest IERS-A data.  If set to False "
         "then the bundled IERS-A file will be used by default (even if a "
         "newer version of the IERS-A file was previously downloaded and cached). "
         "This parameter also controls whether internet resources will be "
         "queried to update the leap second table if the installed version is "
-        "out of date. Default is True.",
+        "out of date. Default is False in Guix for reproducibility.  Refresh"
+        "the python-astropy-iers-data package instead.",
     )
     auto_max_age = _config.ConfigItem(
         30.0,