Incredible blue cylinder of light from craft((NUFORC Note: US Navy missile launch. PD))Driving on I-5 South, south west of Chico CA two of us observed what at first looked like a helicopter facing east shining a spot beam across the sky (not pointing down). There was a very distinct blue cylinder of light emanating from a bright white light which had crisp lines as if it was perfectly uniform in width, it extended a few degrees of azimuth across the sky. Additionally there was a smaller but much wider cone of whitish light emanating in the same direction. However this object was way too high to be a helicopter. The helicopter comparison would seem logical if the object was 100 or 1000 times closer. We stared at this object for what felt like a few minutes discussing what it could be. During this time it became obvious that is not a helicopter and not static as it seemed. Then we noticed the object was moving west and the white light in the shape of a cone moved with it, the blue light column was still there pointing east (not at the ground). At this point it looked like the bright spot of light was the rear of the object and the cone seemed to be the effect as the object moved, kind of like a wake. This conical wake was impossibly big though. As we drove the object moved an extremely long distance West or WSW. The crisp cylinder of blue light appeared to smear and slowly fade over a few more minutes. During this time we could see the cone of light remain while the bright light of the object continued west. As it moved, narrower cones were created. While we were still looking at the blue light cylinder (now smeared, no more distinct lines) we commented how it was blue. I traced the object west and we saw two pickup trucks pulled over on the side of the road liking in the same direction as the event with their phones out. Eventually you could trace the object until it was extremely far away. At this point a fainter cone of light was behind it and looked to pointing up. To better clarify, the blue cylinder looked like a very bright light until it dissipated 5 minutes after it showed up, the conical "light" seemed to not really be light. A good analogy would be that space craft reentry vehicle having a large cone of disturbance behind it, however it would have been impossibly large as the object was so far away. I am an electrical engineer specializing in real time digital signal processing for high precision GPS receivers and the other observer is a general contractor. Both late 30s driving back from a fly fishing trip. I am VERY interested in hearing back from anyone with an explanation for this, whether it can be explained by a natural phenomenon and any other reports of this incident. I would expect 100s or 1000s of people should have seen it due to the duration and nature.