Its constellation consists of 66 low earth-orbiting, cross-linked satellites and has multiple in-orbit spares.
它的星座由66个低地球轨道交联卫星组成，并有多个卫星在轨备用。
2
The 43-minute movie chronicles the 20-year life of Hubble and includes highlights from the May 2009 servicing mission to the Earth-orbiting observatory, with footage taken by the astronauts.
43分钟电影记录了哈勃20年历史，包括从2009年维修任务到绕地轨道天文台的热点和宇航员拍的镜头。
3
The solar ejections that cause auroras can also create geomagnetic storms that can affect spacewalking astronauts, Earth-orbiting satellites, and even communications and power systems on the ground.