High-Precision Orbit Fitting and Uncertainty Analysis of (486958) 2014 MU69

TL;DR

This paper presents a highly precise orbit fitting and uncertainty analysis pipeline for the Kuiper Belt Object MU69, enabling accurate flyby predictions and planning for the New Horizons mission using Hubble and Gaia data.

Contribution

We developed an advanced orbit fitting pipeline combining Hubble and Gaia data to achieve unprecedented precision in predicting MU69's position and uncertainties.

Findings

Successful prediction of stellar occultation in 2017

High-precision orbit determination for MU69

Enhanced planning for New Horizons flyby

Abstract

NASA's New Horizons spacecraft will conduct a close flyby of the cold classical Kuiper Belt Object (KBO) designated (486958) 2014 MU69 on January 1, 2019. At a heliocentric distance of 44 AU, "MU69" will be the most distant object ever visited by a spacecraft. To enable this flyby, we have developed an extremely high precision orbit fitting and uncertainty processing pipeline, making maximal use of the Hubble Space Telescope's Wide Field Camera 3 (WFC3) and pre-release versions of the ESA Gaia Data Release 2 (DR2) catalog. This pipeline also enabled successful predictions of a stellar occultation by MU69 in July 2017. We describe how we process the WFC3 images to match the Gaia DR2 catalog, extract positional uncertainties for this extremely faint target (typically 140 photons per WFC3 exposure), and translate those uncertainties into probability distribution functions for MU69 at any given time. We also describe how we use these uncertainties to guide New Horizons, plan stellar occultions of MU69, and derive MU69's orbital evolution and long-term stability.