Gene, I use a freeware program called Satscape by Scott Hather Similar features to the program you mentioned but designed for windows. Check it out at: http://www.satscape.co.uk/ Rick Tejera President Editor SACnews Saguaro Astronomy Club Phoenix, Arizona saguaroastro@xxxxxxx www.saguaroastro.org -----Original Message----- From: az-observing-bounce@xxxxxxxxxxxxx [mailto:az-observing-bounce@xxxxxxxxxxxxx] On Behalf Of gene lucas Sent: Friday, July 07, 2006 11:11 PM To: az-observing@xxxxxxxxxxxxx Subject: [AZ-Observing] Re: ISS/STS-121 pass -- Freeware to track it Heavens-Above is a great, convenient free source of satellite pass info. You can select any worldwide location, and even customize for a favorite place. Gives the predicted Iridium flares, too. (Probably the best URL for that.) A good "freeware" to download for tracking and predicting satellite passes is STS-Plus, by Dr. David Ransom of Sedona. It allows you to display a track map (projected on the Earth's surface) for any given satellite, using the updated TLEs (Two-Line Elements, the Keplerian data needed to calculate an orbit). This is a DOS program that was originally written for NASA's command centers. It opens up on your PC in a Windows menu, works great. I have used it effectively with the public Astronomy Day display at the Arixona Science Center for a number of years. It also features an "alarm" mode that will "beep" when the selected satellite comes within range. Also allows computing the proper doppler-shifted radio frequencies (for ham radio communications). Here's the URL: http://www.dransom.com/ There are multiple web sites listed there for downloading the TLE ephemeris data. (Note that any tracking program will need updated TLEs, especially for the Space Shuttle (which maneuvers, of course). Have fun! Gene Lucas (17250) Rick Tejera wrote: >Jimmy, >You can get the most current orbital elements from Heavens-Above. > [older stuff snipped, to please the NET NANNY -- I always get bit by over-quoting!! GAL] -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list. -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.