From to [ Shift -1 day | Shift +1 day ] Zoom menu

Plot and as with

Best fit to data (blue line). Reference gradient (red lines):-583ms/day/mrad.
Going will vary with amplitude because sin(θ) ≉ θ

Comments (see all | edit)

03 May 2009 [16:00]
very strange event, amplitude dropped by 1mrad so clock sped up by 1s/day, corrected itself the next morning. Could this have been a spider spinning its web between the pendulum and the casing? This is a really good event to plot as Going vs Amplitude becvause it obeys the pendulum physics beautifully. [link]

Download data

Interval between data points: seconds [either 3 seconds (weather data is duplicated) or multiples of 60 seconds (all data is averaged)].

Contact:, Trinity College, Cambridge