It was early in the morning, clear sky and i took my dog out to go to the bathroom. i was looking at the sky when movement to the right caught my eye. i saw 3 lights that looked like stars moving across the sky at the same speed and what looked like the same distance apart. i originally thought maybe they were satellites, but about that time more movement to the left made me focus on more lights, approx 3 to 4, come rolling across the sky at a high rate of speed, then slow down quickly to get in line with the first ones i saw and continue across towards the northeast. this happened four to five more times with groups of 3 to 4 at a time. what was strange is that i couldn't tell where they were coming from. the sky was clear, no clouds, so i could see the whole sky and they seemed to either shoot down into our atmosphere from outside of it, or out from something that i couldn't see. at almost the end of this sighting came a three light horizontal group that was part of the same object or thing, they were not moving separate but together and it followed the rest of the lights i had been watching. at this point i ran into the house to get my phone. i have an iphone 10, but it doesn't work well in the dark. i got the impression that all of these were high in the sky, but honestly could not say how high they were. there were two more lights that were following along after the others that i tried to get a video of but it just turned out dark. we live in the flight path of the portland international airport and i know what jets, planes and helicopters look and sound like. what i saw was silent and no planes took off or landed during what i witnessed. a couple of minutes later, i began to see the usual airport traffic coming and going.