diff --git a/nav.py b/nav.py
index 13b74e5..f7d8ba0 100644
--- a/nav.py
+++ b/nav.py
@@ -20,7 +20,7 @@ DISTANCES = {
     ("mars", "ceres"): 265.0,
     ("gateway", "milliways"): 42.0,
     ("ceres", "vesta"): 96.0,
-    ("ceres", "europa"): 404.0,
+    ("ceres", "europa"): 399.0,
     ("europa", "io"): 0.25,
     ("europa", "ganymede"): 0.4,
     ("ganymede", "callisto"): 0.8,