Re: Curbed satellite trajectory - GLOBALSTAR M006 & 060 ?

From: Alain Figer via Seesat-l <seesat-l_at_satobs.org>
Date: Fri, 9 Apr 2021 10:16:51 +0200
Hi Karl,

Assuming that you observed  April 5 night I actually found a configuration
that may perfectly explain your strange sighting at 19h15.6m UT. Initially
you were following object 1998-023B which descended from Epsilon to Zeta
UMa according to your observation. It was Globalstar M006 , a flashing
satellite which currently has a 18s rotation period. You must have lost it
visually at its minimum brightness, just when another satellite,
1992-093AV, faster and located a little below, crossed its trajectory a bit
under Zeta UMa, in moving from left to right. The "visual substitution"
must have occurred around 19h15m38s UT.
The inclination of the Globalstar is 52 ° and that of the other satellite
70.7 ° which produced an angular configuration like the one you indicated
in the sketch you sent me. The second satellite, 1992-093AV ,  is a debris
from the disintegration of  Cosmos 2227 rocket  (1992-093B) ; it was a much
faster satellite (altitude = 744 km) than the Globalstar one (altitude =
1883 km). Consequently the visual effect must have been striking because of
the "apparent acceleration" undergone by the object that you were initially
following.

Regards

Alain Figer
48.67 N ; 2.13 E ; 170m a.s.l.
44.57 N ; 6.68 E ; 1850m a.s.l.

Le lun. 5 avr. 2021 à 23:00, Karl Antier via Seesat-l <seesat-l_at_satobs.org>
a écrit :

> Dear all,
>
> I have a question, which may look dumb, but I must admit I never saw
> that before...
> I was smoking a cigarette outside, in Montfuron (France : 43.838° N,
> 5.696° E), when I saw what looks like a satellite in the Big Dipper tail
> tens of seconds before 19h15 UT. I wondered if it could be a Starlink,
> seen its magnitude (+3.5 to +4.0), but I very fast realized it was far
> too slow to be one. But gazing at it, I suddenly had the impression its
> trajectory curbed and took a nearly 70° angle without really changing
> its magnitude, before disappearing... (see attached picture if allowed
> on the list)
> I must admit I did not understand at all what it could be. I wasn't
> drunk or drugged, I am observing the sky as an astronomer for 25 years
> now, I have seen strange things (NOSS triangle formations, etc.), but
> all of them found an explanation... For tens of minutes, I could not
> find any, so I realized I had observed the first real extraterrestrial
> shuttle!!! ;-)
>
> But a few minutes later, I checked on Stellarium, and realized there
> were 2 GlobalStar satellites (M060 and M006) which seems to pass in the
> Big Dipper Tail, with the two trajectories (before and after the curb) I
> observed. On the model, there are not exactly passing at the same place
> at the same time (which must have been the case to explain what I
> observed), but I was wondering if you had a guess on the timing accuracy
> of such satellites predictions?
>
> Thanks in advance for your answers!
> Best regards,
> karl
>
>
> _______________________________________________
> Seesat-l mailing list
> http://mailman.satobs.org/mailman/listinfo/seesat-l
>
_______________________________________________
Seesat-l mailing list
http://mailman.satobs.org/mailman/listinfo/seesat-l
Received on Fri Apr 09 2021 - 03:18:07 UTC

This archive was generated by hypermail 2.4.0 : Fri Apr 09 2021 - 08:18:08 UTC