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China’s first Mars exploration mission (HuoXing-1) has been named as ‘Tianwen-1’ meaning Heaven Inquiry. Tianwen-1 was launched on July 23, 2020. In this paper, the scientific objectives of earlier and current Mars exploration missions worldwide are reviewed, and the scientific objectives, payloads and preliminary scientific investigation plan of China’s first Mars exploration mission are introduced, and expected scientific achievements are analyzed.

Soft error caused by single event upset has been a severe challenge to aerospace-based computing. Silent data corruption (SDC) is one of the results incurred by soft error. SDC occurs when a program generates erroneous output with no indications. SDC is the most insidious type of results and very difficult to detect. To address this problem, we design and implement an invariant-based system called Radish. Invariants describe certain properties of a program; for example, the value of a variable equals a constant. Radish first extracts invariants at key program points and converts invariants into assertions. It then hardens the program by inserting the assertions into the source code. When a soft error occurs, assertions will be found to be false at run time and warn the users of soft error. To increase the coverage of SDC, we further propose an extension of Radish, named Radish_D, which applies software-based instruction duplication mechanism to protect the uncovered code sections. Experiments using architectural fault injections show that Radish achieves high SDC coverage with very low overhead. Furthermore, Radish_D provides higher SDC coverage than that of either Radish or pure instruction duplication.

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Chang'e-4 is the first man-made probe that accomplished landing and roving on the far side of the Moon, which is viewed as a new milestone in the history of Lunar exploration. Beginning with a brief introduction to the progress of domestic and foreign Lunar exploration, this paper reviews the implementation process of the Chang'e-4 project, sorts out the technical breakthroughs achieved, summarizes the exploration achievements, and provides references for subsequent Lunar exploration.