Analysis of Micrometeoroid Environment Characteristics Using Meteor Radar Data from the Meridian Project

Micrometeoroids represent a significant factor threatening the safety of China's spacecraft in space. Historically, numerous incidents of spacecraft anomalies due to meteoroid impacts have been reported, therefore, conducting modeling studies on the meteoroid environment is of great significance. This study utilizes observational data from the Mohe Station of China's Meridian Project to inverse the characteristics of micrometeoroids in near-Earth space, analyze the spatiotemporal distribution characteristics of micrometeoroids over China's mid-to-high latitudes (including their number, velocity, altitude, azimuth, zenith angle, and flux), and retrieve their physical properties such as mass. The results indicate that meteoroid activity exhibits distinct seasonal and diurnal variations: activity is higher in summer than in winter and significantly higher at night than during daytime. In addition, the spatial distribution of meteoroids is non-uniform and primarily concentrated in the northwest direction; their velocities predominantly range between 20 and 80 km/s, and altitudes are mainly concentrated between 75 and 125 km. Comparing the inversed flux results with the classical Grün model revealed good consistency between the two sets of results for larger-sized meteoroids' flux. This research can provide technical support for developing China's independent meteoroid environment modeling studies.