Observations of the Performance of Pendula at the Time of the 2002 December 4 Solar Eclipse in South Australia

Abstract

SummaryIt has been claimed that pendula exhibit anomalous behaviour at the time of solar eclipses. The claims have been that Foucault pendula deviate from the regular motion of their plane of oscillation and that pendula, more generally, change their oscillatory period. At the time of the 2002 December 4 solar eclipse, we made observations of the operation of a Foucault pendulum and a pendulum clock at the University of Adelaide. We were able to set an upper limit of one degree on the deviation of the oscillatory plane of the Foucault pendulum at eclipse time when compared to observations immediately before and after the partial eclipse phases. Our limit on any change of pendulum time periods associated with the eclipse was one part in one hundred thousand.