Flying saucer with multi colored lights near Kingsport, Tn

I was driving home late from school in mid- to late-April 1989.  I had stayed late to work on finals projects and left the college somewhere between 12:30 and 1:00 am.  
I proceed West on I-81 and saw something hovering above the trees on the right side of the road at the top of a steep embankment.  When I got closer, I pulled into the emergency lane and looked up the embankment toward the UFO.  There was lights all the way around the bottom of this craft.  I could see the bottom very clearly.  It was only about 300ft up the hill from me hovering about the trees.  It had two or three different colored lights around the outside on the bottom.  The colors where red, white and green or blue. The bottom was shiny like polished aluminum or chrome.  I could not see the upper portion of the craft.
	The craft made no sound and just set there only 30 or 40 ft above the tree tops. It was probably about 100ft in Dia.  I slowed down to a crawl and looked out my passenger side window up at the bottom of the craft.  I was afraid to get out or stop.  There was no car in view in front of or behind me on my side of the interstate.  I could see cars coming on the opposite side of the road.  I only seen the craft for 1-2 minutes but see if very clearly.
	I pulled away slowly and it was still setting there when I left.  It made no sound.  
I watched the news the next day several times and evidently no one else reported it.  Some people on the other side of the interstate had to see it.
Witness elects to remain totally anonymous; provides no contact information.  PD