HOW TO PREDICT & WATCH SATELLITES
 

A number of web-based programs now exist for you to calculate when and where to see Earth-orbiting satellites from your location―even to show their paths graphically against the stellar background. 

Before searching for satellites, be sure to set your watch to the exact time from the United States Naval Observatory.  Often local phone companies have a number one can call for a recorded time signal as well.  For example, in the San Diego, California area, one can call 619.853.1212.

One of the best online sources for celestial information is Heavens Above. You can use it as a "guest", or you can "register"―both free.  The advantage of registering is that you can store information at the site (e.g., different observing locations, etc.).

Visit the website and click on "Selecting from our huge database".  From here you can select your city, and then follow the directions to get information on satellites passing overhead, complete with exact timings and a star map showing the satellite's path through the constellations!   Also available are data on sunrise and sunset times, constellation maps and much more.

This site will also tell you when and where to view glints of sunlight (flares) off of Iridium satellites.  For these, you must enter the exact latitude and longitude of your location, not just the approximate coordinates of the city you're in.   If you don't have a GPS to get that information, you can type in your address here, click on "Determine Latitude/Longitude", and write down the decimal form of your coordinates.

Next, return to Heavens Above and click on "Enter your coordinates manually".  Follow all directions and then select "Iridium Flares" (or any other calculation you desire).  If you've registered, you won't have to re-enter your coordinates each time you return.

One final tip:  always begin satellite searching at least 5-10 minutes early... just in case!