It says they were overlaid. If that's true, then the effects should still hold true.
Its more than that. They said they spent 45 hours layering the individual photos and "Much of the time was spent painstakingly erasing stars, to reveal the satellites."
alt Hacker News
Its more than that. They said they spent 45 hours layering the individual photos and "Much of the time was spent painstakingly erasing stars, to reveal the satellites."