I observed Lacrosse 4 on 2000 Aug 22 at 09:24 UTC, running 2.98 min late relative to the epoch 00234.4262 elements that I posted yesterday. I alerted Paul Gabriel, who confirmed the late arrival on the next rev, at 10:58 UTC. It now appears that the spacecraft made a second manoeuvre about one rev prior to Paul's observation on 2000 Aug 21 at 10:20 UTC, which further circularized its orbit, and increased its orbital period by about 14 s. This would account for most of its approx 16 s late arrival on 21 Aug. I was suspicious that there may have been a manoeuvre, but chose to attribute it to imperfect obs on 20 Aug, when we were somewhat hampered by bright twilight. Paul and I have obtained quite a few points this morning, which should yield a pretty good orbit. I hope to post it in a few hours. In the meantime, observers should expect the object to be running progressively later, relative the epoch 00234.4262 elements. I suggest adding 14 s for each rev after the epoch to approximate the error. Ted Molczan ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Tue Aug 22 2000 - 05:53:13 PDT