A large light that would continuously stop, hover, and change directions in flight.

On our way home from Logan, we encountered a strange light in the darkening sky.  It was by no means a star and was not blinking like an airplane.  The light it emitted was very bright and large.  At first the odd shape was heading Southwest, then it changed directions and started to go West.  The weird thing was though, was that it would stop in the middle of the sky and just suddenly hover there for a few minutes.  We stopped, jumped out of the truck and proceeded to record a quick video of it.  We were shocked as it flashed blue, white and red very quickly in the video.  We hopped back in the truck and started moving again, trying to get closer although it was dozens of miles away in the air.  When we stopped again to gaze at the orb of light, it hovered again over a mountain and begin to suddenly go out like a light switch had been flicked.  It eventually disappeared, but we were all pretty shaken. In many of the pictures the light seems to be a sphere of some sort, moving in small circles while still hovering in the same spot.