diff --git a/gnu/packages/astronomy.scm b/gnu/packages/astronomy.scm
index 981a46f0d6..b590ce08a9 100644
--- a/gnu/packages/astronomy.scm
+++ b/gnu/packages/astronomy.scm
@@ -1987,6 +1987,8 @@ (define-public python-astral
 (define-public python-spherical-geometry
   (package
     (name "python-spherical-geometry")
+    ;; XXX: Can't be updated to the latest see:
+    ;; https://github.com/spacetelescope/spherical_geometry/issues/227
     (version "1.2.22")
     (source
      (origin