Precise Positions of Triton in 2010-2014 based on Gaia-DR2

Abstract

With unique orbital and physical characteristics, Triton is a very important target because it may contain information of the origin and evolution of the solar system. Besides space explorations, ground-based observations over long time also play a key role on research of Triton. High-precision positions of Triton obtained from ground telescopes are of great significance for studying its orbital evolution and the physical properties of Neptune. As a long-term observational target, Triton has been observed by the 1.56 m telescope of Shanghai Astronomical Observatory since 1996. In this paper, based on our AAPPDI software and with Gaia DR2 as the reference catalog, 604 positions of Triton during 2010-2014 are calculated, with standard errors of 19-88 mas. A comparison between our results and the ephemeris (DE431+nep096) is also given.