diff --git a/hw4-pybind/compute_gravity.hh b/hw4-pybind/compute_gravity.hh
index 77071bd1..56479b21 100644
--- a/hw4-pybind/compute_gravity.hh
+++ b/hw4-pybind/compute_gravity.hh
@@ -1,27 +1,30 @@
 #ifndef __COMPUTE_GRAVITY__HH__
 #define __COMPUTE_GRAVITY__HH__
 
 /* -------------------------------------------------------------------------- */
 #include "compute_interaction.hh"
 
 //! Compute Newton gravity interaction
 class ComputeGravity : public ComputeInteraction {
 
   // Virtual implementation
 public:
   //! Newton gravity implementation
   void compute(System& system) override;
 
   // Accessors
 public:
   //! set the gravitational constant
   void setG(Real G);
 
   // Members
 private:
   //! newton constant
-  Real G = 1.;
+  //Real G = 1.;
+
+  // TEMPORARY:
+  Real G = 6.67384e-11 * 5.97219e24 * std::pow(60*60*24, 2) / std::pow(149597870.700*1e3, 3);
 };
 
 /* -------------------------------------------------------------------------- */
 #endif  //__COMPUTE_GRAVITY__HH__