An approximation to the errors in the planetary ephemerides of the Astronomical Almanac

Abstract

Errors in the planetary coordinates of the Astronomical Almanac are approximated by comparing their fundamental ephemerides, upon which they are based, with a more recent ephemeris. JPL's DE200 provided the fundamental planetary and lunar ephemerides of the Astronomical Almanac for the years, 1984-2002, and DE405 has replaced DE200 in that role, starting in 2003. Recently, new observational measurements have become available, thereby enabling further improvements in the ephemerides, and thus, a measure of the previous errors.