diff --git a/pyproject.toml b/pyproject.toml
index 29a5312e..7e2cd4b1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -27,7 +27,7 @@ dependencies = [
     "matplotlib",
     "papermill",
     "pandas",
-    "photutils >=1.9",
+    "photutils >=1.9,<2",
     "pydantic >=2",
     "pyyaml",
     "platformdirs",