Re: Starlink-65 flare 23 JUN 2020 - negative magnitude

From: Richard Cole via Seesat-l <seesat-l_at_satobs.org>
Date: Thu, 25 Jun 2020 21:49:42 +0000
Francisco,

Thanks for posting that, it was useful to run through my flare model. 
The fact the objects are bright even when not flaring indicates they are 
in open-book mode, so probably ~mag 1-2. From experience, the Starlinks 
from the May 2019 launch are in a variety of modes, some operational 
(earth pointing) and others open-book. This observation indicates that 
those in open-book mode are not all implementing the recent knife-edge 
mode that would make them darker.

The flare position is consistent with the 'standard model' which is that 
some panel on the Starlink is rolled around the velocity vector 
~33degrees from the Sun-facing direction. My guess is that it is one of 
the two mirror-surfaced panels that hold the Ka-band parabolic antennas 
and seem to be separately articulated.

regards

Richard Cole


On 25/06/2020 18:51, Francisco Ocaña González via Seesat-l wrote:
> Hi all,
> 
> I got the report of a flare from a Starlink on the 23rd June 2020. Trails
> of two satellites are recorded in an all-sky image taken by Jaime Izquierdo
> from M30 Observatory, in Madrid. Camera is used for a light pollution
> research project ( https://guaix.ucm.es/azoteaproject ) so exposures are
> long (25 seconds, one image every 2 minutes). And in this case the timing
> was a bit off (+3 minutes, checked afterwards). Actual time of observation
> was 03:36 UT, and trails observed fit very well with Starlink-65 (44276)
> and Starlink-21 (44245), launched on May 24, 2019 and happened to be around
> the 6000th revolution around the globe.
> 
> I have posted it in case someone may find it interesting, especially for
> modelling these flares. The two stars between the two trails are Zeta and
> Epsilon Cygni.
> 
> https://imgur.com/RRxZTNp
> 
> Cheers,
> 
> Paco Ocaña
> _______________________________________________
> Seesat-l mailing list
> http://mailman.satobs.org/mailman/listinfo/seesat-l
> 

-- 
mob:  0771 858 8940
_______________________________________________
Seesat-l mailing list
http://mailman.satobs.org/mailman/listinfo/seesat-l
Received on Thu Jun 25 2020 - 16:50:45 UTC

This archive was generated by hypermail 2.3.0 : Thu Jun 25 2020 - 21:50:45 UTC