diff --git a/src/nature.rs b/src/nature.rs
index 17b8ae2..7071fc9 100644
--- a/src/nature.rs
+++ b/src/nature.rs
@@ -176,7 +176,7 @@ pub fn orbital_velocity(coords: DVec3, mass: f64) -> DVec3 {
     let speed = (G * mass / r).sqrt();
 
     // This generates a perpendicular orbital vector in the prograde direction
-    let perpendicular = DVec3::new(-coords.z, 0.0, -coords.x).normalize();
+    let perpendicular = DVec3::new(coords.z, 0.0, -coords.x).normalize();
 
     return perpendicular * speed;
 }