diff --git a/scenes/tilemap/tilemap.gd b/scenes/tilemap/tilemap.gd
index c89af314..78e0437c 100644
--- a/scenes/tilemap/tilemap.gd
+++ b/scenes/tilemap/tilemap.gd
@@ -707,7 +707,7 @@ func set_coordinates(lon: float, lat: float, course: float) -> void:
         add_mark_from_lon_lat(ship_id, lon, lat, ship_instance, 0.0)
     else:
         _marks[ship_id].position = lonlat_to_world(lon, lat)
-        ship_instance.rotation_degrees = course
+        ship_instance.rotation_degrees = fmod(270.0 + course, 360.0)
     queue_redraw()