RT info:eu-repo/semantics/article
T1 Precession of the non-rigid Earth: Effect of the mass redistribution
A1 Baenas, Tomás
A1 Escapa García, Luis Alberto
A1 Ferrándiz, José Manuel
A2 Ingenieria Aeroespacial
K1 Ingeniería aeroespacial
K1 Celestial mechanics
K1 Methods: analytical
K1 Earth
K1 Reference systems
K1 2504 Geodesia
AB [EN] This research is focused on determining the contribution to the precession of the Earth’s equator due to the mass redistribution stemming from the gravitational action of the Moon and the Sun on a rotating solid Earth. In the IAU2006 precession theory, this effect is taken into account through a contribution of −0.960 mas cy−1 for the precession in longitude (with the unspecific name of non-linear effect). In this work, the revised value of that second-order contribution reaches −37.847 mas cy−1 when using the Love numbers values given in IERS Conventions, and −43.945 mas cy−1 if those values are supplemented with the contributions of the oceanic tides. Such variations impose a change of the first-order precession value that induces relative changes of the Earth’s dynamical ellipticity of about 7.3 and 8.5 ppm, respectively. The corresponding values for the obliquity rate are 0.0751 and 0.9341 mas cy−1, respectively, in contrast to 0.340 mas cy−1 considered in IAU2006. The fundamentals of the modeling have been revisited by giving a clear construction of the redistribution potential of the Earth through the corresponding changes in the Earth tensor of inertia. The dynamical problem is tackled within the Hamiltonian framework of a two-layer Earth model, introduced and developed by Getino and Ferrándiz. This approach allows for the achievement of closed-analytical formulae for the precession in longitude and obliquity. It makes it possible to obtain numerical values for different Earth models once a set of associated Love numbers is selected. The research is completed with a discussion on the permanent tide and the related estimation of the variation of the second degree zonal Stokes parameter, J2, and also the indirect effects on nutations arising from the relative change of the Earth’s dynamical
PB EDP Sciences
SN 0004-6361
LK https://hdl.handle.net/10612/17738
UL https://hdl.handle.net/10612/17738
NO Baenas, T., Escapa, A., & Ferrándiz, J. M. (2019). Precession of the non-rigid Earth: Effect of the mass redistribution. In Astronomy & Astrophysics (Vol. 626, p. A58). EDP Sciences. https://doi.org/10.1051/0004-6361/201935472
DS BULERIA. Repositorio Institucional de la Universidad de León
RD 20-may-2024