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arXiv · 1308.6416

Updated IAA RAS Planetary Ephemerides-EPM2011 and Their Use in Scientific Research

Abstract

The EPM2011 ephemerides are computed using an updated dynamical model, new values of the parameters, and an extended observation database that contains about 680 000 positional measurements of various types obtained from 1913 to 2011. The dynamical model takes into account mutual perturbations of the major planets, the Sun, the Moon, 301 massive asteroids, and 21 of the largest trans-Neptunian objects (TNOs), as well as perturbations from the other main-belt asteroids and other TNOs. The EPM ephemerides are computed by numerical integration of the equations of motion of celestial bodies in the parameterized post-Newtonian n-body metric in the BCRS coordinate system for the TDB time scale over a 400-year interval. The ephemerides were oriented to the ICRF system using 213 VLBI observations (taken from 1989 to 2010) of spacecraft near planets with background quasars, the coordinates of which are given in the ICRF system. The accuracy of the constructed ephemerides was verified by comparison with observations and JPL independent ephemerides DE424. The EPM ephemerides are used in astronavigation (they form the basis of the {\it Astronomical Yearbook} and are planned to be utilized in GLONASS and LUNA-RESURS programs) and various research, including the estimation of the solar oblateness, the parameters of the rotation of Mars, and the total mass of the asteroid main belt and TNOs, as well as the verification of general relativity, the secular variations of the Sun's mass and the gravitational constant, and the limits on the dark matter density in the Solar System. The EPM ephemerides, together with the corresponding time differences TT - TDB and the coordinates of seven additional objects (Ceres, Pallas, Vesta, Eris, Haumea, Makemake, and Sedna), are available at ftp://quasar.ipa.nw.ru/incoming/EPM.

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E. V. Pitjeva. 2013-08-29. Updated IAA RAS Planetary Ephemerides-EPM2011 and Their Use in Scientific Research. https://doi.org/10.1134/s0038094613040059

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