diff --git a/assets/json/gravity.json b/assets/json/gravity.json
index 518f9a97..b3d69475 100644
--- a/assets/json/gravity.json
+++ b/assets/json/gravity.json
@@ -8,5 +8,12 @@
 	"saturn": 0.916,
 	"uranus": 0.889,
 	"neptune": 1.12,
-	"pluto": 0.071
+	"pluto": 0.071,
+	"io": 0.183,
+	"europa": 0.134,
+	"ganymede": 0.146,
+	"callisto": 0.126,
+	"titan": 0.14,
+	"triton": 0.0794,
+	"sun": 28
 }