Re: How inaccurate are predictions made months in advance?

Tony Beresford (
Wed, 29 Apr 1998 22:10:58 +0900

At 21:22 26/04/98 +0900, Tony Beresford wrote:
>With Trakstar the two predictions only differed by 5 minutes! 
 As Mike McCant pointed out in a private message this is actually
87 minutes( nearly an orbit). 
>Mike McCants has stated to me that
>quicksat is not as accurate as trakstar when using old elements
The above should read when using fresh elements, because it doesnt
use the SGP4 algorithm.
Incidentally the Russians are now saying in Press reports that they are
going to lower MIR, using the Progress scheduled for launch May 15,
presumably after the contract with NASA expires when Andy Thomas leaves
Tony Beresford