[ATMoB-discuss] geostationary sat observing weeks are here!

[George Roberts]

I have known about this for years but never shared it with atmobs and I realize now (with Bert's post) that I should.

Geosynchronous Sat observing can be done naked eye although it is best with binoculars.  There are two short periods during the year 
when you can see them near the equinoxes.

Geostationary: 24 hour orbit straight over the equator - this is unstable (because of the moon) and requires propellant to keep it 
there.

Geosynchronous: 24 hour orbit but is tilted so satellite drifts north and south very slowly (no noticable movement over 5 minutes).

There is a fantastic guide on exactly where to look here:

http://www.satobs.org/seesat/Sep-2006/0029.html

The geostationaries are all at -7 degrees for us so that limits where to look but the above email explains where to look within just 
a few degrees - yes just a few degrees of sky.  This is because most of these geostationary satellites have solar panels aligned 
flat to the sun.  When they are near the anti-solar point they flare up and can be as bright as mag 3 or brighter.  Of course at the 
antisolar point they are in the earth's shadow so you want to catch them just a few degrees from going into shadow.  The above link 
helps with this - look at all instructions and diagrams.  Basically if you look tonight you will be looking at dec -7 degrees, RA 
22h 30 min to 22h 0min.  Best in early evening.

You will need a star chart of this area of sky to find any "extra" stars.  Check every half hour or more often because they flare 
only for a little while (and get brighter as they approach earth shadow).

Geometries will be best in a few weeks in early evening and just before dawn but they are excellent right now also.

- George Roberts
http://gr5.org