Residential neighborhood. suburbs and surrounding areas. aircraft seen at 11:30p.M from balcony with my wife. first at a distance and then flew directly overhead. flying west to east. greyish triangle flying slow, with no sound, about 500 feet up. no bright lights but as it flew overhead we could see beneath there were dim (yellowish) lights in rectangular shapes in a v-formation that may have been reflectors. no other lights seen. aircraft seemed smooth surfaced with no wings or flaps. the aircraft was moving slow (much slower than regular plane). seemed unrushed. no emission and again, making no sound at all. observed for approx. 2 minutes or less. lost track of it as it flew over house. very eery. aircraft was almost invisible against the night sky, got the feeling it didn't mean to be seen. life-changing to experience seeing this.