A bright BRIGHT light at twilight that suddenly appeared and disappeared over the tree line about the distance of a blimp in the sky

Driving on Rt 66 heading East from Front Royal my husband was driving and stuttered my name, I looked up and saw a very very bright light. It was brighter than any LED and it was very unusual for the distance, luminosity, and appearance. The distance was above the tree line, like what you imagine a blimp would be as high as. Twilight was just beginning, so stars were barely out and the sky was just starting to get very dark. This was in between the mountains on the highway. The light was shaped like a circle with a sharp ring around the back or base of it with a very short tail of light behind it. It suddenly disappeared, no trail, no trace. We searched for comet or asteroid happenings, but nothing came up. We both felt the hair on the back of our necks stand up.