Tony Beresford reported: > Used Ted's search elements looking for USA 129, bracketed the > time 1 minute before earliest to 1 minute after latest > prediction. This was a pass at 31 degrees maximum elevation > in the West. Used 7x50 binoculars. Saw nothing Tony Beresford USA 129 (96072A / 24680) could have been fainter than predicted, putting it just beyond the reach of 7x50's. I have experienced many faint low west passes, difficult to see even with 11x80's, so I suggest trying again on a better pass. If it still fails to show, then we must consider other possibilities: 1. The magnitude of the manoeuvre could have much different than expected, but its mean motion was ripe for the size of manoeuvre that I estimated. 2. Perigee could have been raised, and apogee lowered, to produce a low drag orbit similar to those of the two KH's in the eastern planes (95066A and 01044A). This would be unprecedented for a KH while still in the operational western plane, but not shocking. Reducing drag to conserve propellant now (at the expense of some resolution), might be a sensible hedge against the potential failure of the replacement launch on the final Titan IVB, believed to be scheduled for 2005 Feb. 3. It could have been de-orbited. At 7.01 years of age, it is nearing its end of life, and has spent the second longest duration in a primary KH plane (the longest was 7.52 years). If USA 129 remains otherwise healthy, but is low on propellant, then the drag-reducing manoeuvres discussed above make sense, and could extend life by up to several years. The two longest KH missions (total time in orbit, including time in s secondary plane) lasted 8 and 10 years, respectively. Ted Molczan ----------------------------------------------------------------- To unsubscribe from SeeSat-L, send a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@satobs.org List archived at http://www.satobs.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Tue Dec 23 2003 - 11:35:46 EST