eliminate remaining reference to /opt/planetstack from python files
diff --git a/planetstack/hpc_observer/run.sh b/planetstack/hpc_observer/run.sh
index 3369a4a..8ebecc9 100644
--- a/planetstack/hpc_observer/run.sh
+++ b/planetstack/hpc_observer/run.sh
@@ -1 +1,2 @@
-python hpc-backend.py  -C /opt/planetstack/hpc_observer/hpc_observer_config
+export XOS_DIR=/opt/xos
+python hpc-backend.py  -C $XOS_DIR/hpc_observer/hpc_observer_config