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  • Perspective
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The progress of extraterrestrial regolith-sampling robots

Abstract

Space exploration has significantly enriched humanity’s understanding of the space environment in which our Earth resides and the evolution of the Solar System. What we know about a celestial body can be greatly enhanced through a thorough analysis of regolith samples. Extraterrestrial regolith-sampling robots are instrumental in acquiring regolith samples for return or in situ analysis in deep-space exploration. This Perspective systematically summarizes the history and latest developments of these robots, covering the basic concepts, historical context and evolution. Extensive insights into the challenges and constraints in sampling extraterrestrial celestial bodies are then explored. An in-depth analysis of the key ground-test technologies that guarantee the reliability and security of extraterrestrial sampling robotic systems is then presented. Next, a comprehensive perspective of the main technical trends in the development of new extraterrestrial regolith-sampling robots is given. Finally, a technical roadmap of China’s future space exploration missions is provided. Extraterrestrial regolith-sampling robots have made great achievements and changed our understanding of the Universe in the past. They will continue to innovate extraterrestrial regolith-exploring methods in even more fundamental ways, and greater achievements are underway.

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Fig. 1: ERSRs in deep-space exploration missions with a soft landing/touching.
Fig. 2: Different extraterrestrial regolith-sampling techniques.
Fig. 3: Environmental conditions of typical celestial bodies in the Solar System.
Fig. 4: Key ground tests for ERSRs.

a, left, NASA/Campo Alto/V. Robles; a, middle and b, middle, Kris Zacny, Honeybee Robotics; b, right, Julie Kleinhenz; c, left and middle, Brian Glass/NASA/Ames; c, right, Carol Stoker

Fig. 5: China’s future deep-space exploration missions.

Earth, Mars, Moon, Jupiter and asteroid, NASA

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All data needed to evaluate the conclusions are present in the paper. Additional data related to this paper may be requested from the corresponding author or T.Z. (buaazt@gmail.com).

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Acknowledgements

The work is financially supported by the NSFC Key Project (grant no. 51635002) and the NSFC Normal Project (51775011). We thank NASA’s V. Robles, B. Glass and C. Stoker, and Honeybee Robotics’ K. Zacny for giving permission to include their images in this Perspective. We also thank J. Rojas and Z. Lin for their helpful suggestions to make the content more concise.

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X.D. and T.Z. designed the framework of the article; T.Z., Z.Z., X.H., S.L. and K.X. conducted the literature review; T.Z., Y.P., X.L., J.D. and W.Z. conducted the perspective; and T.Z., K.X., Z.Y. and X.D. wrote the manuscript.

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Correspondence to Xilun Ding.

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Peer review information: Nature Astronomy thanks Kris Zacny for his contribution to the peer review of this work.

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Zhang, T., Xu, K., Yao, Z. et al. The progress of extraterrestrial regolith-sampling robots. Nat Astron 3, 487–497 (2019). https://doi.org/10.1038/s41550-019-0804-1

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