diff --git a/setup.py b/setup.py
index 24ccab0..43b8fbe 100644
--- a/setup.py
+++ b/setup.py
@@ -57,6 +57,6 @@
       scripts=['bin/fetch_tles.py', ],
       install_requires=['numpy>=1.19.0', 'scipy', 'requests'],
       python_requires='>=3.9',
-      extras_require=["sphinx", "sphinx_rtd_theme", "sphinxcontrib-apidoc"],
+      extras_require={"doc": ["sphinx", "sphinx_rtd_theme", "sphinxcontrib-apidoc"]},
       zip_safe=False,
       )