Toward an Asteroid-Based Autonomous Navigation Framework for Deep Space CubeSats

This paper investigates the feasibility of asteroid-based autonomous absolute navigation for deep-space spacecraft. Unlike GPS-based autonomous navigation, which is available within Earth orbit, conventional deep-space navigation has primarily relied on ground-based tracking through the Deep Space Network. Existing optical navigation methods are generally used for relative navigation near a specific target body, limiting their ability to estimate absolute spacecraft position during long-duration deep-space cruise. To address these limitations, this paper addresses a fundamental question: can a GPS-analogous navigation infrastructure be realized in deep space? To answer this question, we propose an asteroid-based autonomous navigation framework that uses asteroids with known ephemerides as natural reference objects, while estimating spacecraft position from mid-infrared line-of-sight observations. In this paper we propose a novel navigation framework where a mid-infrared camera is used as a navigation sensor to detect thermal emissions from asteroids as point-like sources. The detected asteroid observations are then combined with an asteroid ephemeris catalog and attitude information to generate line-of-sight measurements in an inertial reference frame. Using multiple asteroid line-of-sight measurements, a bearing-only absolute navigation problem is formulated to estimate the spacecraft position without direct range measurements. To examine the initial feasibility of the proposed concept, numerical simulations were conducted using NASA SPICE-based asteroid ephemerides, a heliocentric spacecraft trajectory, a main-belt asteroid catalog, and a synthetic mid-infrared image generation model. In the simulation, asteroids were detected from synthetic images, line-of-sight measurements were generated through centroid estimation, and the position estimation performance was analyzed using multiple asteroid observations. The results indicate that absolute position estimation during deep-space cruise is feasible using only angle measurements from naturally existing asteroids. This study demonstrates the potential of asteroids as distributed natural references analogous to GPS satellites and suggests a new autonomous navigation concept that can complement ground-based tracking for CubeSat-class deep-space missions.