diff --git a/mission/controller/acs/Guidance.cpp b/mission/controller/acs/Guidance.cpp
index 46d98599..89f3d958 100644
--- a/mission/controller/acs/Guidance.cpp
+++ b/mission/controller/acs/Guidance.cpp
@@ -4,24 +4,24 @@ Guidance::Guidance(AcsParameters *acsParameters_) { acsParameters = acsParameter
 
 Guidance::~Guidance() {}
 
-void Guidance::targetQuatPtgIdle(double timeDelta, double sunDirI[3], double targetQuat[4],
-                                 double targetSatRotRate[3]) {
-  //-------------------------------------------------------------------------------------
-  //	Calculation of target quaternion to sun
-  //-------------------------------------------------------------------------------------
-  //  positive z-Axis of EIVE in direction of sun
+void Guidance::targetQuatPtgIdle(const double timeDelta, timeval timeAbsolute,
+                                 const double sunDirI[3], const double posSatF[4],
+                                 double targetQuat[4], double targetSatRotRate[3]) {
+  // positive z-Axis of EIVE in direction of sun
   double zAxisXI[3] = {0, 0, 0};
   VectorOperations<double>::normalize(sunDirI, zAxisXI, 3);
 
-  //  assign helper vector (north pole inertial)
-  double helperXI[3] = {0, 0, 1};
+  // determine helper vector to point x-Axis and therefore the STR away from Earth
+  double helperXI[3] = {0, 0, 0}, posSatI[3] = {0, 0, 0};
+  CoordinateTransformations::positionEcfToEci(posSatF, posSatI, &timeAbsolute);
+  VectorOperations<double>::normalize(posSatI, helperXI, 3);
 
-  //  construct y-axis from helper vector and z-axis
+  // construct y-axis from helper vector and z-axis
   double yAxisXI[3] = {0, 0, 0};
   VectorOperations<double>::cross(zAxisXI, helperXI, yAxisXI);
   VectorOperations<double>::normalize(yAxisXI, yAxisXI, 3);
 
-  //  x-axis completes RHS
+  // x-axis completes RHS
   double xAxisXI[3] = {0, 0, 0};
   VectorOperations<double>::cross(yAxisXI, zAxisXI, xAxisXI);
   VectorOperations<double>::normalize(xAxisXI, xAxisXI, 3);
diff --git a/mission/controller/acs/Guidance.h b/mission/controller/acs/Guidance.h
index 15e88cdc..973c0bd3 100644
--- a/mission/controller/acs/Guidance.h
+++ b/mission/controller/acs/Guidance.h
@@ -25,8 +25,8 @@ class Guidance {
   ReturnValue_t solarArrayDeploymentComplete();
   void resetValues();
 
-  void targetQuatPtgIdle(const double timeDelta, double sunDirI[3], double targetQuat[4],
-                         double targetSatRotRate[3]);
+  void targetQuatPtgIdle(const double timeDelta, timeval timeAbsolute, const double sunDirI[3],
+                         const double posSatF[4], double targetQuat[4], double targetSatRotRate[3]);
   void targetQuatPtgTarget(timeval timeAbsolute, const double timeDelta, double posSatF[3],
                            double velSatE[3], double quatIX[4], double targetSatRotRate[3]);
   void targetQuatPtgGs(timeval timeAbsolute, const double timeDelta, double posSatF[3],