13 Things That Don't Make Sense
Chapter 2
Chapter 2
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The [Pioneer Anomaly](/wiki/Pioneer_Anomaly "Pioneer Anomaly"). This discusses the *[Pioneer 10](/wiki/Pioneer_10 "Pioneer 10")* and *[Pioneer 11](/wiki/Pioneer_11 "Pioneer 11")* space probes, which appear to be veering off course and drifting towards the sun. At the time of writing of the book there was a growing speculation as to whether this phenomenon could be explained by a yet\-undetermined fault in the rockets' systems or whether this was an unidentified effect of gravity. The lead investigator into the progress of the rockets is physicist [Slava Turyshev](/wiki/Slava_Turyshev "Slava Turyshev") of the [NASA](/wiki/NASA "NASA") [Jet Propulsion Laboratory](/wiki/Jet_Propulsion_Laboratory "Jet Propulsion Laboratory") in California who is analysing the data of the rockets' launch and progress and "reflying" the missions as computer simulations to try to find a solution to the mystery.

However, in 2012, after the book was published, Turyshev was able to give an [explanation](/wiki/Pioneer_anomaly%23Explanation:Thermal_recoil_force "Thermal recoil force") to the Pioneer Anomaly.


When did Turyshev explain the Pioneer Anomaly?