2018.P.1.3. Asteroid Orbiting and Landing Exploration with Micro-spacecraft and CubeSat in SECM

Author(s)

Yonghe Zhang (1)
Yamin Wang (1)

Shanghai Engineering Center for Microsatellites, China

Session

P.1

Keywords

Asteroid exploration, low cost, Micro-spacecraft, CubeSats

Abstract

Shanghai Engineering Center for Microsatellites (SECM), which has launched nearly forty satellites into Earth orbit for space science, communication, navigation, and Earth observation, now shows an increasing interest of exploring deep space targets in a low-cost way. Asteroid Resource Exploration Plan (AREX), regarded as the first interplanetary plan of SECM, initiated two year ago and is now still under the research for fine mapping, surveying of planetary resources, exploring of internal structure of asteroid, that could drive the future asteroid mining as well as resource utilization mission.

The AREX is a two-step plan which consists of one preliminary mission: Technology Test and Verification Pathfinder, and final mission: Sample and Return Mission. The Pathfinder plans to send a micro-spacecraft with two CubeSats within 500 kg for orbiting and landing on a near-Earth asteroid. In order to reduce the mission budget, the micro-spacecraft is piggybacked to a Geostationary Transfer Orbit as the secondary payload on the Long March 3 Rocket, then, injects into the desired heliocentric trajectory by multiple lunar flybys.

On the Pathfinder’s 1.5-year primary science phase, the micro-spacecraft begin to approach the target asteroid from a distance of 100000 km for determining shape and pole position. Then, km-distance level flyby trajectories are designed to estimate the mass and rough gravitational field by ground tracking. Global topography and mapping are completed through progressively lower flyby trajectories. In the meantime, multispectral imaging is deployed for mineralogical, ice-water, and organics analysis.
Two CubeSats carry some science payloads to perform specific tasks. For instants, the γ spectrometer needs 2~3 months operation in a low orbit around asteroid, so as to collect sufficient scientific research data. It can be conceived that other science mission will be delayed if the micro-spacecraft work with the γ spectrometer. Besides, the high-resolution images require a very low orbit, on which the micro-spacecraft suffers huge risk because of the irregular gravity of asteroid. Thus, CubeSat I for above-mentioned reconnaissance task is designed to operate under these tough constraints. In addition, CubeSat II is planned to land on the surface of asteroid in free fall and will carry some in-situ payloads for high-resolution surface images, temperature gradient, chemical composition, etc.

In this proposal, the micro-spacecraft, CubeSats, and piggyback launch is designed to reduce the manufacture fee. Autonomous trajectory programming and GNC, data processing onboard is applied for low-cost deep-space operation. A low-cost mission of about 30 million dollars is pursued.