Changes

[[File:Dn11304-1 600.jpg|right|300px|thumb|Trajectories of the Pioneer and Voyager spacecraft.  (The Pioneer anomaly is much too small to be noticeable at this scale.)]]

[[File:Dn11304-1 600.jpg|right|300px|thumb|Trajectories of the Pioneer and Voyager spacecraft.  (The Pioneer anomaly is much too small to be noticeable at this scale.)]]

The '''Pioneer anomaly''' refers to deviations from projected courses for several spacecraft sent to the outer solar system.  The data sent back from both Pioneer spacecraft, [[Galileo]], and Ulysses, represent one of the first meaningful tests of the precision of gravitation predictions over long distances.  The spacecraft have deviated from the courses that scientists predicted using [[general relativity]], as well as [[Law of Universal Gravitation|Newtonian mechanics]], indicating that both theories may be fundamentally flawed.

The '''Pioneer anomaly''' refers to deviations from projected trajectories for several spacecraft sent to the outer solar system.  The data sent back from both Pioneer spacecraft, [[Galileo]], and Ulysses, represent one of the first meaningful tests of the precision of gravitation predictions over long distances.  The spacecraft have deviated from the courses that scientists predicted using [[general relativity]], as well as [[Law of Universal Gravitation|Newtonian mechanics]], indicating that both theories may be fundamentally flawed.

==Discovery==

==Discovery==