diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4af541aa..ff9b3511 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@ will consitute of a breaking change warranting a new major release:
 
 - Persistent TM stores will now create new files on each reboot.
 - Fast ACS subsystem commanding: Command SUS board consecutively with other devices now
+- Star Tracker: Use ground confguration for EM and flight config for FM by default.
 
 ## Fixed
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 037284ea..6bf2a95a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -71,11 +71,13 @@ if(EIVE_Q7S_EM)
       1
       CACHE STRING "Q7S EM configuration")
   set(INIT_VAL 0)
+  set(OBSW_STAR_TRACKER_GROUND_CONFIG 1)
 else()
   set(OBSW_Q7S_EM
       0
       CACHE STRING "Q7S EM configuration")
   set(INIT_VAL 1)
+  set(OBSW_STAR_TRACKER_GROUND_CONFIG 0)
 endif()
 set(OBSW_ADD_MGT
     ${INIT_VAL}
diff --git a/bsp_q7s/OBSWConfig.h.in b/bsp_q7s/OBSWConfig.h.in
index 687d9363..1dff8f7f 100644
--- a/bsp_q7s/OBSWConfig.h.in
+++ b/bsp_q7s/OBSWConfig.h.in
@@ -67,7 +67,7 @@
 #define OBSW_PRINT_MISSED_DEADLINES                 1
 
 #define OBSW_MPSOC_JTAG_BOOT                        0
-#define OBSW_STAR_TRACKER_GROUND_CONFIG             1
+#define OBSW_STAR_TRACKER_GROUND_CONFIG             @OBSW_STAR_TRACKER_GROUND_CONFIG@
 #define OBSW_SYRLINKS_SIMULATED                     @OBSW_SYRLINKS_SIMULATED@
 #define OBSW_ADD_TEST_CODE                          0
 #define OBSW_ADD_TEST_TASK                          0