Research on Calibration Method of Chang 'E-7 Lunar Seismograph Load

The Chang'E-7 mission is planned to deploy China's first independently developed lunar seismometer, which will monitor vibration signals on the lunar surface caused by moonquakes and meteorite impacts. This will provide valuable scientific data for studying the physical mechanisms of lunar seismic activity and the internal structures of the Moon. According to Apollo-era moonquake records, the magnitude of such events is relatively low, making signal detection particularly challenging. As a result, higher performance standards are required for the lunar seismometer. To ensure measurement accuracy and long-term operational stability in the extreme conditions of the lunar environment, it is essential to establish a systematic calibration methodology. This will guarantee that the instrument’s key technical parameters and calibration indicators meet the requirements for scientific exploration and data inversion. Based on the technical criteria for ground-based seismograph network integration, and considering performance specifications such as operating frequency band, resolution, and magnitude range, this paper proposes a comprehensive ground calibration test plan covering critical indicators, including amplitude-frequency response, sensitivity and sensitivity error, linearity, and self-noise levels. Through multiple rounds of ground testing at various development stages, a systematic and quantitative evaluation process for the seismometer's performance has been established. Furthermore, in accordance with the operational requirements during the in-orbit phase, an autonomous in-situ calibration scheme has been designed, along with a proposed manual source calibration method on the lunar surface. This study establishes a robust calibration framework for evaluating the functional performance of the lunar seismometer, providing a systematic approach to performance testing and assessment throughout all phases—from ground testing to in-orbit operation—and laying the foundation for high-precision data acquisition and subsequent scientific analysis.