diff --git a/spacevoxelviewer.py b/spacevoxelviewer.py
old mode 100644
new mode 100755
index e287b79..f4a54c0
--- a/spacevoxelviewer.py
+++ b/spacevoxelviewer.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+
 import numpy as np
 import matplotlib.pyplot as plt
 from astropy.io import fits  # For reading FITS files
diff --git a/voxelmotionviewer.py b/voxelmotionviewer.py
old mode 100644
new mode 100755
index 6abe4fb..fc7b026
--- a/voxelmotionviewer.py
+++ b/voxelmotionviewer.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+
 """
 pyvista_interactive_view_with_rotation_history.py