Update Astropy and add better doc build instructionsHEADmaster

1 files changed, 1 insertions, 1 deletions

diff --git a/README.md b/README.md
index 85a6669..fdd237c 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ Great for unit conversions: https://speedcrunch.org/userguide/advanced.html
 
 ### Astropy
 
-First, clone the submodule with `git submodule init && git submodule update --remote`. Then [build the documentation](https://github.com/astropy/astropy/blob/main/docs/install.rst#building-documentation).
+First, clone the submodule with `git submodule init && git submodule update --remote`. Then [build the documentation](https://github.com/astropy/astropy/blob/main/docs/install.rst#building-documentation) with `tox -e build_docs`.
 
 ### Download web pages