diff --git a/crates/bevy_pbr/src/light.rs b/crates/bevy_pbr/src/light.rs
index 575c926b4ce40..f88083365a3fb 100644
--- a/crates/bevy_pbr/src/light.rs
+++ b/crates/bevy_pbr/src/light.rs
@@ -92,6 +92,9 @@ impl Default for PointLightShadowMap {
 /// approximation for light sources VERY far away, like the sun or
 /// the moon.
 ///
+/// The light shines along the forward direction of the entity's transform. With a default transform
+/// this would be along the negative-Z axis.
+///
 /// Valid values for `illuminance` are:
 ///
 /// | Illuminance (lux) | Surfaces illuminated by                        |