UFO Sighting in Holly, Michigan on June 20th 2015 – 15-18 lights orangish-yellow top & bottom, red center flying in formation

2015jun20 at 11:20pm ufo sighting. there were 15-18 lights that were orangish-yellow on top and bottom, red in the center flying in formation. they were flying rather low (from my vantage point, maybe 20degrees up from horizon) in groups of three in a straight line, from west to east in the northern sky. they seemed to pulse & made no sound, and were traveling at approximately 30mph. when they disappeared behind the trees, i got in my car and drove north about a 1/2 mile to a clearing (appox. 2minutes) where i had clear view for 10miles to the east (the direction which they were headed) and they were just gone. note: as straight as their flight formation was, they may have been one long craft...