Keplerian elements.   N0ONG WX Sat Kepler Editor is designed to work only with AMSAT (verbose) format elements. Import the kepler file from AMSAT using the Open button. Everything other than the  weather satellite elemnts will be removed automatically. Now you can remove specific satellites by pushing the appropriate button. Pressing the Save button will save the edited elements as kepler.dat. The program  was written by Robert Boeckmann and runs on Macintosh OS  X and OS9 and is freeware Screenshot of N0ONG   AMSAT, the Radio Amateur Satellite Corporation, have an excellent explanation of the format. Such element sets can be obtained from the following sources: FTP Dr T S Kelso's data at his website. The astro directories at Nic.funet.fi. The SEDS archive at the University of Arizona Elements at NASA's JPL. A large number of these element sets are mirrored locally including LEO potentially visible satellites (leo2dn.zip). Dr. Kelso's site provides elements for weather, amateur, GPS, comsat and visual objects, to name but a few groups. The SEDS and JPL sites archive Ted Molczan's element file (includes elements not published by NASA/USSPACECOM) and Allen Thomson's element files. The FUNET archives  mirror the JPL and AFIT sites. HTTP Orbital Information  Group (OIG) provides limited elset data after  going through a simple registration processs. New users are first limited  to 20 elsets/24 hours and after a trial period, are allowed to extend the limit to 100 elsets/24 hours. The more popular elsets that are associated  with grouped elsets such as for geostationary, communciations, some visual, Iridium, etc. are not limited. AMSAT's WWW server. NASA's SPACELINK carries shuttle elements. Both  during a flight and prior to it. They also have a file of elements for the  more visual satellites. Alan Pickup maintains frequently updated elsets for Mir , ISS and the shuttle (when it's up). Ken Ernandes web site carries element sets updated  every Monday, Wednesday, and Friday (except holidays). Relatively up-to-date elements for the tethered satellite TiPS can be  found at the US Naval Research Lab. The elements provided will have to be text edited with carrage returns to conform to  the requirements of most satellite tracking programs. Check sums are not used in the NRL issue. NRL uses the designation provided by US Naval Space Command "00006" and not sat cat. "23937" and International Designation 96029F as used by USSPACECOM/OIG. Unfortunately, these elements are not  provided by OIG as this payload was a piggy-back to a classified military sat. These elements can also be found in the molczan elsets but are not updated frequently. You can also find "ready-to-go" elements (without checksums) for TiPS  in Alphonse Pouplier's Web-page in his elset  "visi.zip". Normally downloaded late Thursday or Friday is the low earth orbit elset and highly eccentric orbit elset leo2dn.zip and eccen2.zip respectively, obtained from OIG's elset  database by volunteers from SeeSat-L. Listserv AMSAT run a listserver which distributes elements. Send a  message to listserv@amsat.org asking to be added to the KEPS list. The NASA shuttle elements mailing list provides you with exactly that. Send a message with the words 'subscribe STSTLE "Your name"' in the body to listproc@spacelink.msfc.nasa.gov. Netnews Dr Kelso posts elements to sci.space.news sci.space.shuttle         whilst AMSAT post elements to rec.radio.amateur.space