. 2010, 28(08): 110-115.
Around the manned spacecraft's orbits in 300 to 500km altitude, there are all kinds of charged particles, neutral atmosphere, the electromagnetic fields, space debris etc. The space environment fluctuations in a manned spacecraft's orbit can significantly affect the safety of astronauts and spacecraft. The charged particles can cause SEU, SEL and the discharge of spacecraft's surface, even threaten the astronauts' safety. The retarded effects of neutral atmosphere make the spacecraft's orbit to descend. Oxygen denudation and oxygen contaminations of atmosphere also affect the solar cell's efficiency and the normal work of thermoregulation materials. To ensure astronauts' safety and normal operations of manned spacecraft, Space Environmental Monitors (SEMs) have been or will be mounted on Chinese manned spacecraft. Detection of SEMs enables us to understand better the space environment in the manned spacecraft's orbit, and to provide a good space environment service for astronauts and spacecraft. In addition, from the data of SEMs, we will conduct various scientific researches. The development of Chinese manned spacecraft is divided into 3 steps, and SEMs are used in each step. Space environmental detection in the first step is to have a preliminary understanding of space environment of manned spacecraft's orbits, and to provide the ensuring service for the formal manned flight. The second step considers Chinese feature. The two instruments installed can realize an integrated detection of charged particles and atmospheric environment. The first detector can detect multi-direction particles, multi-energy spectrum, radiation dose and LET spectrum. The second detector can monitor atmospheric density, composition and contamination. The following step of space environmental detection pays attention to the safety of astronauts and spacecraft, as well as the new areas of detecting plasma, neutrals, cosmic rays and debris.
