Balloon-shaped, illuminated floating object in the night sky

I was driving to get some dinner when I saw a strange, illuminated, hot air balloon-shaped object hovering in the sky.  The distance above the ground was about as high as an airplane would go, but it remained idol as I drove right underneath it and was motionless.  My first thoughts were "Hey, it's New Years Eve, maybe it's some kind of celebratory blimp or something," but as I continued staring at it while I drove, the shape wasn't like anything I've seen before.  
As I just about veered off the road since I couldn't bring my eyes away from it, it began to fall north, slowly making its way across the sky and fading into an orange, star-like shape, disappearing into the atmosphere.  I'd always thought the notion of UFOs was ridiculous and imaginative hoaxes, I couldn't come up with any kind of explanation for the phenomena. 
I was curious if anyone else saw this strange object that night.