Lewis decay prediction
Alan Pickup (alan@wingar.demon.co.uk)
Fri, 26 Sep 1997 19:46:08 +0100
The latest elset for Lewis is:
Lewis 222 x 207 km
1 24909U 97044A 97269.60253286 .02192090 25336-5 99705-3 0 1445
2 24909 97.5549 167.7974 0011296 157.6698 202.5752 16.21871313 5479
showing a fall from a 232 x 216 km orbit during the past day.
My SatEvo analysis suggests that decay may occur about September 28.8.
The evolution gives a mean error of 0.1 seconds for the satellite's
motion over the preceding 1.4 days (max error 0.3 sec), in comparison
with the ten equator crossings during this time for which I have OIG
elsets.
Geomagnetic conditions have been quiet over the past few days, but could
become disturbed on the 27th if the Earth catches the effect of a solar
coronal mass ejection following a major solar flare on the 24th. If this
happens, the atmospheric density at Lewis's height is likely to increase
and its decay be brought forward by a several hours (depending on the
duration and intensity of the disturbance).
The following SatEvo-predicted elsets do *not* include any geomagnetic
allowance...
Lewis 214 x 203 km
1 24909U 97044A 97270.03410995 .02745155 41324-2 10530-2 0 91339
2 24909 97.5530 168.3021 0008493 147.3501 212.7024 16.24072959 5548
Lewis 205 x 196 km
1 24909U 97044A 97270.52659607 .03558080 73884-2 10552-2 0 91338
2 24909 97.5519 168.8792 0007230 145.3442 214.7029 16.27138415 5624
Lewis 193 x 185 km
1 24909U 97044A 97271.01800512 .05227047 17483-1 10603-2 0 91333
2 24909 97.5504 169.4580 0005696 143.3324 216.7065 16.31338190 5709
Lewis 184 x 178 km
1 24909U 97044A 97271.26316240 .07011419 34310-1 10653-2 0 91339
2 24909 97.5493 169.7481 0004749 142.3234 217.7098 16.34290729 5745
Lewis 172 x 167 km
1 24909U 97044A 97271.50779246 .11170271 95901-1 10756-2 0 91339
2 24909 97.5478 170.0391 0003561 141.3116 218.7139 16.38563199 5781
Lewis 147 x 145 km
1 24909U 97044A 97271.75153348 .36840304 12677+1 70258-3 0 91335
2 24909 97.5450 170.3314 0001687 140.2947 219.7176 16.47632897 5825
Lewis 123 x 123 km
1 24909U 97044A 97271.81215071 1.77121937 26481+2 88145-3 0 91337
2 24909 97.5434 170.4049 0000632 140.0387 219.9660 16.56224840 5834
Current elsets for this and other selected objects are updated throught
the day in the file select.tle, available via my SatEvo WWW page.
Alan
--
Alan Pickup | COSPAR site 2707: 55d53m48.7s N 3d11m51.2s W 156m asl
Edinburgh | Home: alan@wingar.demon.co.uk +44 (0)131 477 9144
Scotland | SatEvo satellite page: http://www.wingar.demon.co.uk/satevo/