Black Triangle over North Texas Circa 1985, 1986

I have been recounting this event since that time in either 1985 or 1986 in Plano Texas.  I am not quite sure what I saw. It first appeared as dim light in the distant night sky.  The light appeared to be slowly moving from 20 miles away NE to SW. I mentioned to a friend that was there and he noticed it but paid it no mind. We first surmised that it was a helicopter.  Several minutes had passed and I noticed that it was moving ever closer but I could not hear the operation of the machine.  I watched it as it floated directly overhead. It made no sound and appeared to be black or gun metal gray and machined on the bottom (lines or groves in patterns). It was triangular in shape with a light in each corner. I stared at it for a second.  The rest of the group appeared to pay it no attention at all even though it was right above us. It was stationary above us at about a 100 feet.  After staring for a minute it started to slowly move to the east.  I walked the alley di! rectly underneath it trying to follow. As I followed the craft it appear to notice me following.   At that time it started to ascend into the sky. I imagined that it would rise into the clouds but it did not.  After ascending for a couple of seconds it just disappeared completely.  No one spoke of the incident but I have recounted the story many times to my family since it happened.  I had not heard of a triangular UFO at the time so it struck me as a bit odd.  The movie  Contact came out and my brother called me on the phone to state that it was odd that they used a triangular UFO in the movie in light of the story I had always told.  He had never heard of triangular UFOs either until that time. I now know that black triangles are a common siting and that vanishing is a common phenomenon associated with them.  I am sorry that I cannot remember the exact month or year but I know that school was in at the time and it was around 1985 or 1986.  I do remember the media stating that pe! ople had reported a UFO siting over north Texas at the time. That made it clear in my mind that what I saw was not my imagination.