RE: how useful are these old elsets?

jhunt@eagle1.eaglenet.com
Tue, 14 Jan 97 09:49:05

Dave's statement is *generally* true, but in the case of these *classified* 
satellite TLEs, you might want to use what *is* available if you want to try 
to locate them.
These TLEs are the latest elements calculated from OLD actual past 
observations. Personally I think you stand a pretty slim chance of locating 
them with +2000 day old elements but hey, something is better than nothing.  

As to, "are they still in orbit"; well, OIG's d(a)ta base still lists them 
as "no elements available" so it seems they are still in orbit. I believe if 
they had decayed they would list them as "decayed" even though they are 
classified sats and OIG doesn't provide elements for them.

Jeff Hunt <jhunt@eagle1.eaglenet.com>

--- On Tue, 14 Jan 1997 08:20:33 -0600 (CST)  Ryan Rudnicki <RR03@swt.edu> 
wrote:

>My question:  Why are the elements below in the .tle file?  Are the objects 
>whose elset age is over 1000 days still in orbit?  Are these orbits stable 
>enough that they don't need refreshing too often?  Is it a case of too many 
>satellites and too few refreshers?  The .tle file I'm using is a Ted 
Molczan file dated 09.I.97 and downloaded from Mike McCants' web site.