Polar motion

Polar motion of the Earth is the motion of the Earth's rotational axis relative to its crust.^[2]^: 1 This is measured with respect to a reference frame in which the solid Earth is fixed (a so-called Earth-centered, Earth-fixed or ECEF reference frame). This variation is a few meters on the surface of the Earth.

^ Folgueira, M. (2005). "Free polar motion of a triaxial and elastic body in Hamiltonian formalism: Application to the Earth and Mars" (PDF). Astron. Astrophys. 432 (3): 1101–1113. Bibcode:2005A&A...432.1101F. doi:10.1051/0004-6361:20041312.
^ Lambeck, Kurt (2005). The earth's variable rotation : geophysical causes and consequences (Digitally printed ed.). Cambridge: Cambridge University Press. ISBN 978-0521673303.

[1] Folgueira, M. (2005). "Free polar motion of a triaxial and elastic body in Hamiltonian formalism: Application to the Earth and Mars" (PDF). Astron. Astrophys. 432 (3): 1101–1113. Bibcode:2005A&A...432.1101F. doi:10.1051/0004-6361:20041312.

[Lambeck-2] Lambeck, Kurt (2005). The earth's variable rotation : geophysical causes and consequences (Digitally printed ed.). Cambridge: Cambridge University Press. ISBN 978-0521673303.

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