diff --git a/astroquery/heasarc/core.py b/astroquery/heasarc/core.py
index 703aafc867..e5cabd9d33 100644
--- a/astroquery/heasarc/core.py
+++ b/astroquery/heasarc/core.py
@@ -17,7 +17,6 @@
 
 
 def Table_read(*args, **kwargs):
-    # why does if commons.ASTROPY_LT_5_0 not work on Windows?
     if commons.ASTROPY_LT_5_1:
         return Table.read(*args, **kwargs)
     else:
diff --git a/astroquery/utils/commons.py b/astroquery/utils/commons.py
index 98582a0501..47e6b4e210 100644
--- a/astroquery/utils/commons.py
+++ b/astroquery/utils/commons.py
@@ -59,7 +59,10 @@ def FK4CoordGenerator(*args, **kwargs):
 ASTROPY_LT_4_1 = not minversion('astropy', '4.1')
 ASTROPY_LT_4_3 = not minversion('astropy', '4.3')
 ASTROPY_LT_5_0 = not minversion('astropy', '5.0')
-ASTROPY_LT_5_1 = not minversion('astropy', '5.1')
+
+ASTROPY_LT_5_1 = not minversion('astropy', '5.1dev197')
+# Update the line above once 5.1 is released
+# ASTROPY_LT_5_1 = not minversion('astropy', '5.1')
 
 
 @deprecated('0.4.4', alternative='astroquery.query.BaseQuery._request')