My boyfriend was driving North on TX-121 while on the phone with me, and described the event. He noticed it mainly because it was at night and the object was so bright. At first he thought it was a plane and didn't mention it to me until about after 13 or so minutes, it took off rapidly. He said it had been hovering the entire time he had been driving on the highway. He got excited and a little agitated when I pressed for details, he said it wasn't a cigar shape, but completely flat and didn't leave any trails when it zipped off. After it took off, it just disappeared. He tried to convince himself it was a jet or something, but as far as I know jets don't hover and planes and helicopters have blinking lights and cannot behave the way he described them.