Analysis of The Anomalous Orbital-Energy Changes Observed in Spacecraft   Flybys of Earth
  In March 2008 anomalous behavior in spacecraft flybys of Earth was reported in Physical Review Letters, Volume 100, Issue 9, March 7, 2008, in an article entitled "Anomalous Orbital-Energy Changes Observed during Spacecraft Flybys of Earth".   The data indicate unaccounted for changes in spacecraft speed, both increases and decreases, for six different spacecraft involved in Earth flybys from December 8, 1990 to August 2, 2005. The article states that, "All ... potential sources of systematic error .... [have been] modeled. None can account for the observed anomalies.... Like the Pioneer anomaly ... the Earth flybys anomaly is a real effect .... Its source is unknown."   In the present article it is shown that the Earth flybys anomaly would be caused by a very small acceleration [in addition to that of natural gravitation], centrally directed and independent of distance, the same effect as that which the Pioneer anomaly exhibits. How that effect operates to produce the observed results is analyzed. A cause of the centrally directed accelerations is presented. 
Roger Ellman (The-Origin Foundation, Inc)