Chandler wobble
Earth's axis wanders
The Chandler wobble is a small, periodic shift in Earth's axis of rotation, causing the poles to trace a roughly circular path over about 433 days.
Named for astronomer Seth Carlo Chandler, who identified it in 1891.
The wobble affects precise astronomical measurements and GPS calculations, though its amplitude is only about nine meters at the poles.
Earth measurement science
- geodynamicsScience of Earth's motion
- mantleCovering or wrap
- ocean circulationMovement of seawater globally
- atmospheric pressureWeight of air above
groundwater · ice sheet · seismology · GPS · gravimetry
Rotating axis gradually reorients
- gyroscopeSpinning disc measuring orientation
- torqueRotational force measurement
- angular momentumRotational motion quantity
- inertiaResistance to altered motion
rigid body · spin · moment of inertia · centrifugal · dynamics · equilibrium · stability
Maximum oscillation displacement
- dampingDissipation of vibrational energy
- excitationStimulation of response
- resonanceAmplified oscillation at natural frequency
- frequencyRate of recurrence
periodicity · cycle · fluctuation · nutation · libration · perturbation · harmonic · decay
geodesy
Earth measurement science
- geodynamicsScience of Earth's motion
- mantleCovering or wrap
- ocean circulationMovement of seawater globally
atmospheric pressure · groundwater · ice sheet · seismology · GPS · gravimetry
precession
Rotating axis gradually reorients
- gyroscopeSpinning disc measuring orientation
- torqueRotational force measurement
- angular momentumRotational motion quantity
inertia · rigid body · spin · moment of inertia · centrifugal · dynamics · equilibrium · stability
amplitude
Maximum oscillation displacement
- dampingDissipation of vibrational energy
- excitationStimulation of response
- resonanceAmplified oscillation at natural frequency
frequency · periodicity · cycle · fluctuation · nutation · libration · perturbation · harmonic · decay · spectral analysis