I saw a triangular shaped object rotating slowly in the sky..Had four lights in it...

I was watching tv... when I looked out of my window... Over the roofs of the facing houses across the parkinglot I could see a triangular shaped opbject slowy rotating while moving slowly south.. the object had four lights.. One in the center..the others in the tips of the object... The center light was blueish..while the others were purple green and yellow.. I opened my window to hear if it was a plane or a helicopter.. but it didn't make any sound whatsoever...It couldn't have been an airplaine of any kind any way.. 'cause the object moved way to slow for that... Nor have I ever seen a airplane which rotates in slow motion..
Date of alleged incident may be approximate.  We wonder whether the sighting could have been caused by advertising lights.  PD