If you watch the sky about an hour after the sun goes down, you may see some “moving stars”．But they're not real stars.They are manmade satellites.And the biggest of all is the International Space Station (ISS国际空间站)．
If you watch the sky about an hour after the sun goes down, you may see some “moving stars”．But they're not real stars.They are manmade satellites.And the biggest of all is the International Space Station (ISS国际空间站)．