In Southern Utah, our best views begin tonight @ 10:43 PM, Thurs @11:04PM, and Saturday 6/7/08 @10:14 PM, and Monday 6/9/08 @9:23 PM when the ISS/Discovery will make a visible pass from NW to SE. Tonight and Thursday will be quick low-horizon passes lasting about a minute. Saturday and Monday passes will fly directly overhead, lasting from 2-3 minutes each!Approximately 2,000 satellites are currently in earth orbit. Thousands of smaller pieces of junk also circle the globe. Most are faint and rendered invisible. But depending on who's counting, anywhere from 100 to 300 satellites can be seen with the unaided eye. These are generally more than about 20 feet in length and anywhere from 100 to 400 miles above Earth, a region called "Low-Earth Orbit".
The International Space Station is by far the biggest and brightest hunk of technology circling the planet. Its solar arrays span 240 feet (73 meters). The main modules are together 146 feet (45 meters) long. It stands as tall as a nine-story building and weighs 412,000 pounds (186,900 kilograms). And right now, with the space shuttle Discovery attached, it is even larger.
Traveling around the Earth at 18,000 mph (28,970 kilometers per hour) at an average altitude of 240 miles (386 kilometers), the station can appear to move as fast as a high-flying jet airliner, sometimes taking about four to five minutes to cross the sky, visible to the unaided eye as a point of light similar to aircraft lights.
For more general information on tracking the International Space Station as it passes over your area, go to spacewatch/iss viewing and scroll down to When and Where to Look. Or, see this Nasa Site which allows you to enter your country, then click on your state, then your city & see what will be visible in your area for the next 10-days. Concentrate on those passes with the highest Max Elev (anything above 50 Degrees is good -- 90 Degrees would be directly overhead).