From: Giuseppe N. Gerbore >Is attitude data ( i.e. Iridium antenna orientation) calculated directly >from TLEs? No. The orientation of a satellite is not included in TLEs. Most TLEs are generated from observations only (radar, visual) and so this reporting format doesn't include what you can't determine. Some are expected orbit e.g. NASA space shuttle TLEs before launch. Of course the various groups controlling the satellites have more information about the orientation but this data isn't fed to the people who calculate most of the TLEs. The orientation of many (most?) *active* satellites is highly controlled by their owners. Each has a different technical reason (e.g. point antenna at earth, spin stabilize, point solar panels towards sun, etc). Because of this we just assume the satellite is in it's nominal orientation. This works extremely well for iridiums. Also this means when we see flashing satellites it usually means the satellite is spinning/tumbling and therefore no longer under control although there are exceptions for instance a satellite might be spin stabilized. - George Roberts http://gr5.org _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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