[time-nuts] OT: Far-out space navigation from sideways satnav signals

[Jim Lux]

On 4/18/13 4:01 AM, David J Taylor wrote:
> An interesting novel use of GPS "stray" signals....
>
> "ESA’s retired GIOVE-A navigation mission has become the first civilian
> satellite to perform GPS position fixes from high orbit.  Its results
> demonstrate that current satnav signals could guide missions much
> further away in space, up to geostationary orbit or even as far as the
> Moon. "  See:
>
>   http://www.esa.int/Our_Activities/Space_Engineering/Far-out_space_navigation_from_sideways_satnav_signals
>
Interesting..

I know there's a bunch of analysis about how to use GPS at the moon. you 
need to look at the GPS satellites on the far side of the earth, grazing 
the limb.