Formula for the Chandler Period (Free Wobble of Planetary Bodies)
First published: 2025
Brief summary
Numerical simulation of the Chandler wobble -- Earth's ~433-day free polar motion cycle -- derives its period from the planet's instantaneous viscoelastic response, with the method also applied to measuring Mars's equivalent wobble.
Article
Formula for the Chandler Period (Free Wobble of Planetary Bodies) is a peer-reviewed journal article published by Geophysical Research Letters (AGU) in 2025. It focuses on numerical simulation of the Chandler wobble -- Earth's ~433-day free polar motion cycle -- derives its period from the planet's instantaneous viscoelastic response, with the method also applied to measuring Mars's equivalent wobble.
The analysis focuses on ~433 days (Earth Chandler wobble), also discusses Mars's measured equivalent wobble period. It also considers numerical simulation compared to observation. This gives the cycle claim a specific numerical and evidential setting rather than presenting periodicity only as a visual impression.
The article reports the following result: The Chandler wobble is a cyclic change in the rotation pole's position with a period of about 433 days on Earth; the Chandler wobble period is governed by the instantaneous response of the planet-forming material. The interpretation is strongest when measurement uncertainty, nonlinear dynamics, boundary conditions and alternative physical mechanisms are tested explicitly.
For cycles researchers, the article brings together chandler wobble, polar motion, 433-day period, planetary rotation. It is relevant to physical and geophysical systems in which oscillation, reversal, recurrence and nonlinear dynamics must be distinguished from random variability.
Because it is a peer-reviewed journal article, the article is a strong starting point for discussion in the Physics & Geophysics forum, although its conclusions should still be compared with later replications and updated datasets.
Source details and credits
- Source / publisher: Geophysical Research Letters (AGU)
- Source type: Peer-reviewed journal article
- URL type: WWW
- Credits: Geophysical Research Letters (AGU)
- URL: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2024GL112997