It doesn't have much of an atmosphere, but there is a trace of one, mostly due to its magnetic field trapping the solar wind, and to material flung up from the surface after violent impacts from comets and asteroids.
水星上基本上没有大气层,但有一些大气
痕迹,主要是磁场捕捉到太阳风,以及彗星和小行星猛烈撞击后抛起
物质。