Weird lights high up in the sky flying in a straight line formation

About 4:15 in the morning on May 1rst I was outside with my dog and saw what looked like two identical satellites that were about as bright as a 1rst magnitude star moving out of the WNW sky . They both were moving one behind the other in straight line about 10 degrees apart and continued crossing the sky maintaining the same distance apart as they traveled towards the ESE . I went back in the house thinking how weird that was and about 10 minutes later when I looked out the window I saw two more lights moving in the same exact path as before . I know it's impossible for a satellite to circle the Earth in ten minutes so I ran back outside to see what was going on , only this time new satellites kept appearing one after the other all in a perfectly straight line and all equally spaced until there were six of them moving out of the WNW passing close to Arcturus coming nearly overhead then dimming out one by one in ESE sky .They each took several minutes to fly! by . There was no noise . I've an amateur astronomer for about 45 years and have never seen anything like this before . What were they ?