PRISM TLE

Hi Mike, I am having doubts about PRISM again. During two passes today first I used
Object J and the doppler did not fit. Next pass I used Object B and that fitted ???
Have a nice weekend. 73 OZ1MY, Ib

Everything has now changed ;-)
I analyzed the pass at 22:05 UTC with 16° elevation (used the latest keps day 30.5077) and both TLE.
It seems, YES – Ib, you are right. Will listen to the next pass with 72° elevation.

prism_b_vs_j_3001_2205

PRISM_J
1 33500U 09002J 09030.50771363 -.00000396 00000-0 -42973-4 0 299
2 33500 098.0479 142.2293 0055415 308.7033 050.9214 14.80585224 1075
PRISM_B
1 33493U 09002B 09030.50777114 .00000131 00000-0 24202-4 0 357
2 33493 098.0473 142.2341 0019370 330.2396 029.7732 14.80606051 1099

23:40 UTC , 72° elevation pass

prism_b_vs_j_3001_2340
… very strange. My midnight pass at 23:40 UTC shows the same result. The TLE for Object B is now matching much better to PRISM again.

Mike,
The fact that both objects are very close together there is a strong probability that the tracking stations are getting the objects transposed. If you remember this has happened before. What will define which one is PRIM will be the RCS Data published on the Space-Track site.
If one is a rocket casing the RCS Data will discriminate one against the other very clearly.
Colin VK5HI.

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