Green light lit up the entire sky and a small light moved horizontally before fading outI was riding with a close friend and co-worker from Louisville to Burnside, KY to spend the weekend at Lake Cumberland. Somewhere close to the midpoint of our trip the entire sky lit up with a teal green light (the EXACT location is somewhat of an estimate - I used the GPS on my Blackberry to mark the location on Google Maps but I guess I didn't save the location as a favorite and lost it). I don't know what I was thinking at the time, but I must have thought it was a shooting star or lighting or something along those lines because as soon as the light in the sky faded I leaned forward so I could look up. I scanned the sky fairly quickly left to right and right under the headliner (I'm estimating 60 or 70 degrees up from the horizon) I saw a greenish light fading out. It appeared about the same size as an average star in the sky aside from its color. As soon as I spotted it, it was already fading out (I watched that particular spot in the sky for 2 or 3 seconds max). I leaned back in my seat and I didn't say anything immediately until the driver said something along the lines of "what the ____ was that?" or "did you see that?". He described the light in the sky nearly identically to how I did and after we talked about that for a moment I realized that it didn't just light up in one spot like a flare or shooting star, but it lit up the ENTIRE sky. We were riding in his Expedition so we had plenty of surface area on the windows around us, but I couldn't fathom what would have lit the sky up to the point where I saw it out peripherally as well. Also, I guess he leaned forward before I did or locked onto the object before I did (I don't know which one as I wasn't looking at him or paying any attention to his movements because I was completely focused on what was going on) but he saw the object moving horizontally across the sky before its light faded out. He said he leaned forward just enough to see it moving (from his perspective) about 2 inches under the point where the headliner and top of the windshield meet and it moved in a line almost completely parallel to this point. The sky was slightly overcast but I did notice that stars were fairly visible at that time. We were in the car another 90 minutes and I distinctly remember the sky being almost crystal clear when we got to the cabin at Lake Cumberland (we were fairly high in the hills there and had a great view). There weren't many cars on the road at the time (Highway 127) but I did notice a car that was about 300 yds up ahead tapped their brakes a couple of times as soon as the sky lit up.