diff --git a/.travis.yml b/.travis.yml
index cff7bacd93f673297f21a6fac91d2560f6f61a27..bfa74b9537bdb2ad2d16f543a69145cc543274f7 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,7 +13,7 @@ notifications:
 matrix:
   include:
     - os: osx
-      osx_image: xcode9
+      # osx_image: xcode9 # don't specify an image here to use the default
       compiler: clang
     - os: linux
       compiler: gcc