diff --git a/pyproject.toml b/pyproject.toml
index aa1c102..ba9fbf2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,7 +23,7 @@ python = "^3.8"
 skyfield = "^1.21"
 numpy = [
     { version = "<1.25", python = "3.8.*" },
-    { version = "^1.25", python = "^3.9" },
+    { version = "^1.25", python = ">=3.9,<3.13" },
 ]
 skyfield-data = ">=3,<6"
 python-dateutil = "^2.8"