LONEStar: The Lunar Flashlight Optical Navigation Experiment

TL;DR

The paper addresses autonomous optical navigation for a spacecraft in heliocentric space using planet, Earth, and Moon observations. It presents LONEStar, a ground-based processing workflow implementing triangulation algorithms (DLT, Midpoint, LOST) and light-time corrections within a batch OD framework to achieve heliocentric localization without radiometric data. The study reports three core demonstrations: instantaneous triangulation with Mercury–Mars, sequential triangulation with Jupiter–Saturn, and dynamic triangulation over multi-day timescales, plus Earth–Moon localization; it also shows OPNAV-only orbit determination achieving DSN-level fidelity when Earth/Moon data are included. The results validate the practicality of planet-based OPNAV for deep-space missions, enabling autonomous navigation with reduced reliance on radiometric tracking and offering educational value through a student-led operations team.

Abstract

This paper documents the results from the highly successful Lunar flashlight Optical Navigation Experiment with a Star tracker (LONEStar). Launched in December 2022, Lunar Flashlight (LF) was a NASA-funded technology demonstration mission. After a propulsion system anomaly prevented capture in lunar orbit, LF was ejected from the Earth-Moon system and into heliocentric space. NASA subsequently transferred ownership of LF to Georgia Tech to conduct an unfunded extended mission to demonstrate further advanced technology objectives, including LONEStar. From August-December 2023, the LONEStar team performed on-orbit calibration of the optical instrument and a number of different OPNAV experiments. This campaign included the processing of nearly 400 images of star fields, Earth and Moon, and four other planets (Mercury, Mars, Jupiter, and Saturn). LONEStar provided the first on-orbit demonstrations of heliocentric navigation using only optical observations of planets. Of special note is the successful in-flight demonstration of (1) instantaneous triangulation with simultaneous sightings of two planets with the LOST algorithm and (2) dynamic triangulation with sequential sightings of multiple planets.

Figures (45)

• Figure 1: The Lunar Flashlight spacecraft. Shown here are the major spacecraft subsystems and components Smith:2023 (left) and the spacecraft during integration and testing at Georgia Tech (right).
• Figure 2: Original Lunar Flashlight mission concept of operations Hauge:2023.
• Figure 3: Visualization of as-flown Lunar Flashlight trajectory as seen in Earth-centered ecliptic ICRF. After about 5 months within the Earth-Moon system (left), LF was ejected into a heliocentric trajectory (right). Shown in dark blue is the portion of the trajectory corresponding the LONEStar imaging campaign. Tick marks indicate the LONEStar elapsed time relative to the reference epoch 2023-JUL-22 00:00:00 UTC. The Moon’s orbit is shown in red.
• Figure 4: Georgia Tech Mission Operations Center (MOC) during Lunar Flashlight mission.
• Figure 5: Illustration of Lunar Flashlight spacecraft configuration, important coordinate frames, and orientation of camera field of view (FOV).