[amsat-bb] Re: satellite los footprints

[Joe Fitzgerald]

On 3/25/2013 6:42 PM, Ken Ernandes wrote:
> 2.  If you decide to give the users the ability to input their location, them the option to provide either a single minimum elevation angle or a local map -- i.e., 360 individual minimum elevations as a function of Azimuth.  It's much easier to project this and the user is generally interested in an unobstructed LOS with respect to his/her location.
>
>

It's not the best resolution but in the image below, you can see how 
there are "cut outs" in the circles surrounding NASA's ground stations - 
the software has clearly implemented the idea Ken outlined above.  For 
example, there is apparently some obstruction to the south east of the 
Hawaiian tracking station.  If the sub-satelite point is inside the 
white line it's AOS.  The surface of the earth visible to the shuttle, 
on the other hand, is simply a red circle, just faintly visible in this 
image.

http://vault.newsfromspace.com/missions/sts114/STS114_land-5.jpg

-Joe KM1P