Selection of Satellites for Iridium Flare prediction on the GSOC web site

Chris Peat (
Mon, 26 Jan 1998 09:18:44 +0100

Joe Dellinger asked if the flare prediction programs will work with the
newly launched Iridium satellites. This is just to inform you all that our
flare prediction service at

selects only those satellites in their operational orbits, which are
characterised by a mean motion of 14.342... revs/day.  We do this to avoid
giving potentially false predictions, although it means, of course, that we
might miss a few flares from "rogue" satellites or those still climbing to
their operational height.

I would also like to take this opportunity to mention the new orbit display
that is generated on the server and can be reached via the satellite
information page. It works for all the satellites in our database, and the
display includes three different views of the orbit - from above the orbital
plane, from above the satellite, and a ground track over a "flat" earth map.
At the moment, the display is static (but can be refreshed with a page
reload), but I am planning to include a Java applet soon that will move the
spacecraft along its orbit. This display will work with ANY web browser
because it consists just of GIF files generated on the server, and is our
response to all those people who said their browsers don't support ActiveX

If you want to use a shortcut, try the URL;

which will show you the orbit of Vanguard 1 (NORAD no. 5). If you know the
NORAD number of the satellite you wish to display, just replace 5 with the
correct number. If the satellite is not in our database, you will get an
error message. We currently have all the spacecraft in Ted Molczan's file. I
will be adding a page soon which lists the satellites in the database
according to search criteria.


Chris Peat, Anite Systems
Currently working at the German Space Operations Centre near Munich