A Titan IV-B is scheduled to be launched on Aug 16 at 23:45 UTC. I believe that the payload is a Lacrosse, as I explained in this earlier post: http://www2.satellite.eu.org/seesat/Aug-2000/0017.html I hope that official 2-line elements for the Titan 2nd stage will be released soon after launch, as they were after Lacrosse 3 was launched, but in case that does not happen, I have produced pre-launch elements for orbits of inclination 57 deg and 68 deg: T-IV 2nd stage 9.8 3.0 0.0 4.8 v 1 70001U 00230.16663982 .00000000 00000-0 00000-0 0 07 2 70001 57.0090 47.0200 0177212 165.0881 195.5654 15.06051010 07 T-IV 2nd stage 9.8 3.0 0.0 4.8 v 1 70002U 00230.16663982 .00000000 00000-0 00000-0 0 08 2 70002 68.0000 37.0500 0177212 169.0000 195.5000 15.06050101 05 These orbits assume an on-time launch at 23:45 UTC. If the launch is delayed, then I will issue new elements. My guess is that the orbit will be inclined at 57 deg, but the evidence is sufficiently conflicting, that I believe it prudent to prepare to observe the 68 deg orbit as well. The elements are based on Lacrosse 2 and 3, and should be accurate to within a few minutes of time, assuming that this mission is similar. The RAAN could be off by a few degrees, so the track may not be quite as precise as the time. The elements are for the Titan 2nd stage; however, the Lacrosse payload should trail a short distance behind it for a day or two, before it manoeuvres to its final orbit. Here is how Mike McCants described his observation of Lacrosse 3 and its Titan IV 2nd stage, soon after their launch in Oct'97: http://www2.satellite.eu.org/seesat/Oct-1997/0377.html If tomorrow's launch occurs on time, then the orbit will initially be visible to Southern Hemisphere observers in evening twilight. Australian observers should expect to see it approximately 5 hours after launch. I have not checked whether or not there will be a simultaneous morning twilight window. North American observers can look forward to a morning twilight observation window, beginning on 20 August for the 57 deg orbit, and on 19 August for the 68 deg orbit. This window will open for progressively more northerly latitudes in the days that follow. The weather forecast for 16 and 17 August is more likely than not to violate launch constraints, so a delay may occur. If, as I suspect, the launch time is tied to one of the existing Lacrosse orbital planes, then the launch time would be progressively earlier for each day of delay. If the reference plane is that of Lacrosse 3, then the launch should occur 19 minutes earlier for each day of delay. If the reference plane is that of Lacrosse 2, then the launch should be 14.4 minutes earlier for each day of delay. 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
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