Please help explain this unknown light in the sky. Not ISS. Not a star or comet. Too slow So a few nights ago I walked outside on my front lawn and sat down on the tailgate of my truck. I was facing north. I was looking down and towards the house across the street. Out of no where a bright light caught my eye. I looked up and didn't see anything. A couple of seconds later another light appeared, then disappeared. I pin pointed it to the left of the left of 'Kochab' star in 'Ursa Minor.' I was locked onto the sky at that point... So I kept watching and it kept happening. It was irregular. Zero regularity; it kept doing this. Bright flashes of light and subtle growing of light for a 20 minute period moving towards the north east. Randomly doing this with 2 seconds, sometimes with 5-7 second intervals. Even the type of flashing was irregular. Sometimes flashing following by flashing and other times growing light following by growing light. I've never seen anything like this in my life. I know what the space station looks like, I've seen it countless times as well as space junk. They're constant lights. And we all know what planes look like in the night sky. Constant red lights with regular blinking of white light. It was traveling in a straight path with little to no noticeable curvature. In no way could it have been reflecting light. No doubt it was projecting its own light.

Anything similar you've known or heard about? Please help explain this.
That sounds like a high altitude nonfunctioning satellite to me. For example, a rocket body or upper stage that is tumbling. I have seen these types of satellites flash  many times before.

The pattern is irregular because of the spinning and changing angle to the Sun.