Session
Technical Session XI: Science/Mission Payloads I
Abstract
Microsat and nanosat developers have mastered the challenges involved in developing low-cost, high-performance satellite missions in low Earth orbit. Here we describe a proposed small-microsat-scale (~20 kg) planetary exploration mission based on the same design approach used in those LEO missions. The “GRavimetric Asteroid Surface Probe” (GRASP) spacecraft is being designed by Gedex and SFL, to carry out fundamental science and exploration activities on the surface of a small asteroid. It will carry a novel, extremely-high-accuracy space gravimeter instrument (VEGA, the VEctor Gravimeter for Asteroids) being developed by Gedex. Emplaced on an asteroid’s surface, VEGA will make measurements of the local gravity field strength (with nano-G accuracy) and direction (with arc-minute accuracy). A single such measurement will enable an asteroid’s mass to be determined, even for a very small asteroid. Measurements at multiple locations will enable inferences to be made about the asteroid’s internal density distribution, and hence its internal structure and composition. While much of the equipment used in LEO nanosats and microsats is suitable for use in GRASP, the mission’s asteroid landing and roving objectives, and the asteroid orbit and surface environment, lead to several design features not generally seen in LEO missions. Here we review GRASP’s mission objectives, highlighting the challenges which drive the design. We discuss the main mission and system level requirements which GRASP will meet, and describe the overall GRASP design.
An Asteroid Lander/Rover for Asteroid Surface Gravity Surveying
Microsat and nanosat developers have mastered the challenges involved in developing low-cost, high-performance satellite missions in low Earth orbit. Here we describe a proposed small-microsat-scale (~20 kg) planetary exploration mission based on the same design approach used in those LEO missions. The “GRavimetric Asteroid Surface Probe” (GRASP) spacecraft is being designed by Gedex and SFL, to carry out fundamental science and exploration activities on the surface of a small asteroid. It will carry a novel, extremely-high-accuracy space gravimeter instrument (VEGA, the VEctor Gravimeter for Asteroids) being developed by Gedex. Emplaced on an asteroid’s surface, VEGA will make measurements of the local gravity field strength (with nano-G accuracy) and direction (with arc-minute accuracy). A single such measurement will enable an asteroid’s mass to be determined, even for a very small asteroid. Measurements at multiple locations will enable inferences to be made about the asteroid’s internal density distribution, and hence its internal structure and composition. While much of the equipment used in LEO nanosats and microsats is suitable for use in GRASP, the mission’s asteroid landing and roving objectives, and the asteroid orbit and surface environment, lead to several design features not generally seen in LEO missions. Here we review GRASP’s mission objectives, highlighting the challenges which drive the design. We discuss the main mission and system level requirements which GRASP will meet, and describe the overall GRASP design.
