Matte black chevron-shaped object hovering silently over median of I-78, with downward spotlights.

I am not sure that chevron is the right shape but it seems closest to what I saw.  I was driving west on I-78 after coming off of I-287 south.  I am guessing that it was in September because it was dark and yet it was warm enough for me to have the car windows open.  As I came around a curve in the interstate I could see over the median a black object with a number of spotlights shining down onto the median.  As I got closer I could see that it was triangular in shape but with the (back?) side sort of dented in (chevron?) The vehicle was very angular and not curved in any way.  It spanned the median, so it was about fifty feet in diameter, and I would say about the same in length.  There were about five or six of the spotlights that shone straight down in almost a pinpoint of light - definitely not floods but spots.  It was matte black, and it was hovering, and was absolutely silent.  I saw at least one other car coming the other direction on the interstate but it was impossible to tell if they saw it also. The object stayed there as long as I could see it in my rearview mirror.
 I was about 19 at the time and was on my way home from work.  I had been away to university for one year and had decided not to go back, and went to work full time.  I had worked overtime for two hours which was typical for that time.  I did not stop because I was a)fearful that the occupants might see me and b)even more afraid that my father would be angry if I arrived home later than I said I would.
Date is approximate.  PD