# Precise CCD positions of Triton in 2014-2016 using the newest Gaia DR1 star catalogue

## TL;DR

This paper reports precise CCD measurements of Triton’s position from 2014-2016 using Gaia DR1 star catalogue, improving positional accuracy for Neptune’s satellite.

## Contribution

It provides new high-precision Triton positions based on extensive CCD observations and Gaia DR1 data, enhancing ephemeris accuracy.

## Key findings

- Mean O-Cs are 0.042 and -0.006 arcsec in RA and Dec.
- Observation dispersions are about 0.012 arcsec.
- Data covers 15 nights of observations.

## Abstract

755 new CCD observations during the years 2014-2016 have been reduced to derive the precise positions of Triton, the first satellite of Neptune. The observations were made by the 1 m telescope at Yunnan Observatory over fifteen nights. The positions of Triton are measured with respect to the stars in Gaia DR1 star catalogue. The theoretical position of Triton was retrieved from the Jet Propulsion Laboratory (JPL) ephemeris nep081xl, while the position of Neptune was obtained from the JPL ephemeris DE431mx. Our results show that the mean O-Cs (observed minus computed) are 0.042 and -0.006 arcsec in right ascension and declination respectively. The dispersions of our observations are estimated at about 0.012 arcsec in each direction.