I posted: >The Centaur burn for 3 minutes at 22000 miles and the residual fuel and oxidizer >dump after payload separation should be visible as two naked-eye "comets" about >6+ hours after launch from the entire western hemisphere since this will occur >over the equator at longitude 90 west. The launch is scheduled for 01:39 UT (Nov 11). The circularization burn would then be about 07:50 UT. The fuel dump should be some time after 08:10 UT. (Or perhaps the Centaur will do a depletion burn.) The IUS burn for DSP 22 was estimated to be magnitude 1 from a dark sky. Here is the predicted GTO coast tle: DSP 23 GTO coast 1 99991U 07315.12700000 0.00000000 00000-0 00000-0 0 00 2 99991 26.6000 270.0000 7081000 353.0000 0.0000 2.19648000 03 Predictions for Austin, TX: *** 2007 Nov 11 *** Times are UT *** Mag Hrs Min Alt Azi Hgt Range R A Dec 6.4 3 30 58 259 3410 3707 22 1.3 19.4 6.4 3 35 72 249 4156 4252 23 9.4 22.4 6.6 3 40 82 221 4896 4920 0 0.9 23.3 6.9 3 45 83 162 5623 5640 0 39.7 23.2 7.1 3 50 80 131 6333 6373 1 9.5 22.7 7.3 3 55 76 120 7022 7100 1 33.1 22.0 7.5 4 0 73 116 7690 7810 1 52.4 21.3 Inside the Earth's shadow for about 95 minutes 9.3 5 35 58 122 16909 17397 4 8.9 10.7 9.6 6 5 59 128 18753 19241 4 28.1 8.4 9.7 6 35 59 136 20200 20676 4 44.3 6.3 9.9 7 5 60 145 21286 21751 4 58.6 4.2 9.9 7 35 60 154 22034 22499 5 11.7 2.2 10.0 7 45 60 157 22211 22680 5 15.9 1.6 10.0 7 55 59 161 22353 22827 5 20.0 0.9 Here is the predicted circular orbit tle: DSP 23 and Centaur 1 99992U 07315.33000000 0.00000000 00000-0 00000-0 0 00 2 99992 4.0000 285.0000 0001000 154.0000 0.0000 0.99965000 03 Predictions for the Centaur for Austin, TX: Mag Hrs Min Alt Azi Hgt Range R A Dec 10.0 7 50 56 163 22292 22882 5 12.9 -2.9 10.0 8 0 56 164 22292 22887 5 22.9 -3.1 For the DSP 22 launch, the prediction was also for orbital circulization over longitude 90 west, but the observations indicated about 96 west. So there is a lot of uncertainty in these predictions. If the launch is delayed, the altitude and azimuth values will still be correct and the declination will still be correct, but the RA will be in error by the amount of the launch delay. The intrinsic magnitude for the Centaur should be about 3.0, but the DSP payload will probably be 2 or 3 magnitude fainter. Mike McCants ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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