http://www.newsweek.com/spot-international-space-station-iss-when-how-1112011

The International Space Station is always orbiting the Earth at about 17,000 miles per hour, or five miles per second. But its incredible speed doesn't mean it's impossible to see.

The station makes a complete orbit of Earth once every 92 minutes, passing above the heads of everyone down below. Because the station is about 240 miles above the planet, it doesn't appear to be traveling thousands of miles per hour to the naked eye.