diff --git a/SGP4.cpp b/SGP4.cpp
index fb9f4d4..5531fa8 100644
--- a/SGP4.cpp
+++ b/SGP4.cpp
@@ -68,7 +68,6 @@ void SGP4::SetTle(const Tle& tle) {
     mean_motion_ = tle.MeanMotion() * TWOPI / Globals::MIN_PER_DAY();
     bstar_ = tle.BStar();
     epoch_ = tle.Epoch();
-    orbit_number_ = tle.OrbitNumber();
 
     /*
      * error checks
@@ -1289,6 +1288,4 @@ void SGP4::Reset() {
             recovered_mean_motion_ = perigee_ = period_ = 0.0;
 
     epoch_ = Julian();
-
-    orbit_number_ = 0;
 }
diff --git a/SGP4.h b/SGP4.h
index 8a433ab..f52d6f1 100644
--- a/SGP4.h
+++ b/SGP4.h
@@ -93,11 +93,7 @@ public:
     Julian Epoch() const {
         return epoch_;
     }
-
-    unsigned int OrbitNumber() const {
-        return orbit_number_;
-    }
-
+    
 private:
     void Initialize(const double& theta2, const double& betao2, const double& betao, const double& eosq);
     void DeepSpaceInitialize(const double& eosq, const double& sinio, const double& cosio, const double& betao,
@@ -267,7 +263,6 @@ private:
     double perigee_;
     double period_;
     Julian epoch_;
-    unsigned int orbit_number_;
 };
 
 #endif