diff --git a/mars_rover/worlds/mars_curiosity.world b/mars_rover/worlds/mars_curiosity.world
index 66ec6bc2..1e3f63eb 100755
--- a/mars_rover/worlds/mars_curiosity.world
+++ b/mars_rover/worlds/mars_curiosity.world
@@ -1,8 +1,5 @@
 <?xml version="1.0" ?>
 <sdf version="1.11">
-  <world name="default">
-<?xml version="1.0" ?>
-<sdf version="1.6">
   <world name="default">
     <physics name="1ms" type="ignored">
       <max_step_size>0.001</max_step_size>