Series of lights moving in a straight line across the sky.There were 6 equally spaced lights flashing in sequence in the southern sky. At a glance they appeared to be stars until further examination showed them to be flashing in sequence and in a straight line. They covered an area (depending on their distance away) of 2 miles to 50 mi. We heard no sound and then they moved slowly from east to west. We observed this for about ten minutes.I questioned others who live south of us and no one had heard any helicopters or anything else around this time.