RE: 81-33b 12389 final orbit observation ?

From: Ted Molczan via Seesat-l <>
Date: Sun, 12 Jul 2015 00:04:44 -0400
Tristan Cools wrote:

> Maybe i observed what could be the final orbit of this Cosmos 1263 rocket.
> At 21:12 utc just passing below bootes mag 0.  Orange color maybe already
> glowing....   greetings tristan cools

Assuming that you observed from Bruges, then mag 0 when passing near Bootes was within the range of the predicted
magnitude of 2.0 +/-2. This is based on standard magnitude 5.3 (1000 km, 90 deg phase angle) and coefficient of phase
1.23 mag/rad. These were derived in 2001, from 952 visual observations by Russell Eberst of this model of rocket stage.
Based on the TLE nearest in epoch, the altitude at the time was 140 km - too high to have been self-luminous.

Alain Figer observed at about the same time and reported mag 0 or 0.5, consistent with the predicted maximum brightness
from his location of mag 0.8 +/-2.

Ted Molczan

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Received on Sat Jul 11 2015 - 23:05:39 UTC

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