diff --git a/Shaders/projection.frag b/Shaders/projection.frag
index 8e360af2b..b972e664d 100644
--- a/Shaders/projection.frag
+++ b/Shaders/projection.frag
@@ -1,3 +1,5 @@
+// From there it's a matter of multiplying the moon position by gl_ModelViewMatrix to get it into eye space
+
 // uniforms
 uniform int enable_overlay;
 uniform int auto_vfov;