[amsat-bb] Re: AO-51 obseved solar eclipse?

[Alexandru Csete]

Greetings,

I ran a simulation using the Celestia space simulator and could indeed
observe a partial solar eclipse as seen from AO-51 :)
I have recorded the simulation to a video and you can watch it on
Youtube:
http://www.youtube.com/watch?v=7ET8BhbqmVk

I couldn't find any 3d model of AO-51 so I used a model of AO-7 - sorry
for that. Also note that I used TLEs from today to generate orbital
data for Celestia so the time and may not be scientifically accurate.

If you want to run the simulation for yourself, watch from other
angles, etc., you can get Celestia for free from
http://shatters.net/celestia/
You'll need to add the data files for AO-51 in the "extras" folder;
you can use mine to begin with. There is a .zip file here:
http://files.oz9aec.net/video/SolarEclipse/

You'll also find the H.264 encoded video there that you are free to
download (~100MB).

73
Alex Oz9AEC


On Tue, 13 Jul 2010 13:10:41 -0400
"Mark L. Hammond" <marklhammond at gmail.com> wrote:

> Hello Masahiro,
> 
> Thank you for your message!  You have made a great observation, and I
> think you are exactly right about the cause of the observed "glitches"
> in the telemetry.  Usually at this point in its orbit we would observe
> AO-51 charging its batteries at a steady rate from fully illuminated
> panels.
> 
> >From what I've read from page 43 here:
> http://eclipse.gsfc.nasa.gov/SEpubs/2010/TP214171a.pdf  the eclipse
> was from 18:15 to 20:52 UTC.    Look also at the areas experiencing
> eclipse.
> 
> Please be aware that the "clock" on AO-51 runs fast.  It is now about
> 3 minutes fast, so look at telemetry timestamped from about 18:18
> until 20:55 UTC.
> 
> Since the duration of the solar eclipse was 2 hrs 39 min (or 159 mins)
> and AO-51 orbits every 100 minutes or so, it could have been affected
> two times.
> 
> I've plotted some of the telemetry collected from that period
> (telemetry from 1800-2130utc)  and posted it here:
> http://www.amsat.org/amsat/ftp/telemetry/ao51/2010WOD/July2010/Wd071100_1800to2130utc_solar_eclipse.xls
> 
> And here's a screenshot of AO-51 at the time:
> http://www.amsat.org/amsat/ftp/telemetry/ao51/2010WOD/July2010/ao51_11July2010_2045utc_solar_eclipse.jpg
> 
> 73!
> 
> Mark N8MH
> 
> 
> 
> 2010/7/13 Masahiro Arai <m-arai at a.email.ne.jp>:
> >
> > Total solar eclipse was observed in southern Pacific Ocean at 11th
> > July. I checked AO-51 WOD file. Total Array I shows glitch at
> > 2043-2045z. AO-51 was located on east of Argentina at the time. Is
> > this glitch made with solar eclipse??
> >
> >
> > AO-51 Wd071100
> > 2010/7/11
> > UTC    Total Array I [mA]
> > 20:35   -2.111
> > 20:36   -0.323
> > 20:37   -0.323
> > 20:38    1.465
> > 20:39   -0.323
> > 20:40  528.851
> > 20:41  321.472
> > 20:42  307.170
> > 20:43  183.815
> > 20:44  190.966
> > 20:45  176.664
> > 20:46  249.962
> > 20:47  300.019
> > 20:48  396.557
> > 20:49  498.459
> > 20:50  519.912
> > 20:51  729.079
> > 20:52  634.328
> > 20:53  936.458
> > 20:54  843.495
> > 20:55  948.972
> >
> >
> > WOD file
> > ftp://ftp.amsat.org/pub/amsat/telemetry/ao51/2010WOD/July2010/Wd071100
> >
> > AO-51 WOD decoder
> > http://tinyurl.com/DK3WNsoftware
> >
> >
> > 73
> >
> > Masa  JN1GKZ    Tokyo Japan
> >
> >
> >
> > _______________________________________________
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> 
> 
>