diff --git a/astrometry.spec b/astrometry.spec
index 78f9897..47542e5 100644
--- a/astrometry.spec
+++ b/astrometry.spec
@@ -221,9 +221,9 @@ make SYSTEM_GSL=yes all py extra ARCH_FLAGS="%{optflags}"
 
 
 %install
+export PYTHON=%{__python3}
 %{make_install} SYSTEM_GSL=yes \
                 INSTALL_DIR=%{buildroot}%{_prefix} \
-                PYTHON=%{__python3} \
                 PY_BASE_INSTALL_DIR=%{buildroot}%{python3_sitearch}/%{name} \
                 INCLUDE_INSTALL_DIR=%{buildroot}%{_includedir}/%{name} \
                 LIB_INSTALL_DIR=%{buildroot}%{_libdir} \
@@ -268,6 +268,7 @@ rm -f %{buildroot}%{_docdir}/%{name}/LICENSE
 install -m0644 astrometry-data*/*.fits %{buildroot}%{_datadir}/%{name}/data
 
 %check
+export PYTHON=%{__python3}
 make test ARCH_FLAGS="%{optflags}"