How's the surrounding when it won't work. It works best if you have clear sky view.

if i am not mistaken there is an increasing activity on the sun's surface. solar flares can cause disruptions on satellites in orbit that are exposed directly. in minor cases it will cause reboots and freezes on onboard computers, in worst cases... you would not want to know.... 

http://www.swpc.noaa.gov/

http://spaceweather.com/