lower semisphere

例句：

1. 1. The lower semisphere is the region of space beyond the Earth's atmosphere.
   下半球是地球大气层之外的太空区域。
2. 2. The lower semisphere is where most planets are located.
   下半球是大多数行星所在的区域。
3. 3. The lower semisphere is also known as the outermost part of the solar system.
   下半球也被称为太阳系的最外层。