Pale Blue Light in Night Sky Over Seward, NebraskaIt was approximately 1800 hours when I was traveling westbound on I-80. To the south I noted a light coming towards me heading north to cross the highway. It caught my eye because the leading light on this craft was a pale-blue, or almost aqua in color and did not flash.As I watched it start to pass over me I noticed only a rear light, which I can only describe as a dull dirty white glow. It was difficult to make out the shape of the object because of the time of day, it was twilight, and the sun had gone down below the horizon.I thought that it might be a helicopter and I expected to see that shape, but that is not the impression I got of it from its silhouette. The object was not moving fast and seemed very low, if I had to guess, I would say that it was maybe 500 feet above the ground and travelling at approximately 100 mph.In closing, I spotted this object coming from the South, heading North and it seemed to be passing slightly west of Milford, Nebraska. There were no flashing lights, as one would expect to see from an FAA aircraft. If you have any answers as to what this may have been, I would truly appreciate it. I have never seen anything that would make me report it, but this object was extraordinary to me.Thank You Sincerely