Would you know how many satellites are in orbit at this moment?

The first artificial satellite- Sputnik- was launched into space on October 4, 1957 by the Soviet Union. Since then, things have been busy! As of August 19, 1999, there is a total of 2616 satellites in Earth orbit, as well as 90 space probes (that is, objects not orbiting the Earth but sent to the Moon, planets, comets, etc.). On top of that, there are about 6100 pieces of debris out there as well: pieces of broken up satellites, rocket boosters, lost tools, etc. etc., for a grand total of roughly 9000 objects in space. The U.S. alone accounts for about 3850 of that total.

The North American Aerospace Defense Command (NORAD) is in charge of keeping track of all that stuff. Their website at www.spacecom.af.mil/norad/index.htm has lots of information about how they do it. I got the numbers above from their Satellite Boxscore webpage.

If you want to see some of those satellites, try the Heavens Above webpage. Enter your latitude and longitude (or pick it from a huge database of locations) and it will predict satellite passes for your location. I have mine bookmarked and check it every clear night! Many satellites are easily bright enough to see with the naked eye, and some are bright enough to see in daylight!