Maybe somebody here can help me understand what I saw a couple of years ago. Basically, I saw what appeared to be two satellites on a collision course. One was

Maybe somebody here can help me understand what I saw a couple of years ago. Basically, I saw what appeared to be two satellites on a collision course. One was bright and travelling across my FOV from left to right fairly slowly. Then another much dimmer and faster light appeared in the right of my FOV and appeared to be on a collision course. At the moment of apparent collision (from my POV) they appeared to very rapidly orbit around each other some number of times, before continuing on their original course. I believe the dim one was moving more slowly than before, but I am unsure. This happened around July of 2018 I believe. From lat,lon of about 49.25,-123.12 looking south at the night sky at about 45°. My best guess is it was an optical illusion, the two satellites were at different altitude and only appeared to be on a collision course from my point of view. Some sort of lensing effect? I don't know.