diff --git a/starfield.f90 b/starfield.f90
index b5ad811..7debea4 100644
--- a/starfield.f90
+++ b/starfield.f90
@@ -29,7 +29,7 @@ subroutine do_starfield (nbstar)
   integer, intent(in)     :: nbstar
   integer         idx, color
   real            px, py, sz
-  do idx=0, nbstar
+  do idx=1, nbstar
     px = (rand(0) * 10.00) - 5.00
     py = (rand(0) * 10.00) - 5.00
     sz = (rand(0) *  0.16) + 0.16