I saw about 30 satellites moving in single file, straight line trajectory, constant speed, spaced evenly apart

First, let me say that I have never seen a ufo, and I believe that what I saw was satellites.
I was offloading or delivering gasoline to a station in sauk rapids, mn.  I was actually daydreaming about seeing a UFO,  when I looked up into the night sky I say a small white light moving at constant speed, and in linear trajectory, in a northernly direction (approximately).  It was at very high altitude.  As I watched it I noticed it had a second one about 4 seconds behind it.  As I continued to watch this, I noticed that there was a continuous stream of these objects (satellites).  Over the course of several minutes,  I counted about 30 of these objects.  I've never seen this many satellites moving together in a straight line, and I considered this to be noteworthy (hence this report)