1)unshaded area,无阳影区2)shadow of the sun,太阳阴影区3)ascian,无影区人4)twilight band,半阳影区，微明区5)radioheliograph,无线电太阳摄影机6)lack of yang,无阳
用法例句
When satellite orbits within the shadow of the sun and in vacuum and thermal environment,mirror thermal distortion in space-to-ground laser communication links is analyzed with the method of finite element analysis.
