Approx. 10:45 pm edt, 7/5/2019. 5 miles se of houghton lake, mi. three green lights in a row moving slowly across the sky, almost directly overhead. the center light was solid, other two were flashing. we initially thought it was an aircraft, but i noted to my father that all the lights were green. he immediately checked flighttracker on his phone - no aircraft in the vicinity. we continued watching the lights which appeared to be slowing, almost stopped. then all three lights jumped instantly to a different location in the sky, three times in about ten seconds, the resulting locations forming a diamond pattern. then while still, all three lights flashed yellow to red three times, turned solid green, then began moving w/sw at a tremendous speed. not knowing how large or how high this anomaly was, we estimated that if this was the height of an airliner at cruising altitude, the speed would be approx. 2400 mph. my father and i continued watching the completely silent anomaly move out of sight.