A bunch of California residents were freaking out this week over mysterious lights that seemed to be orbiting overhead:

Here was a shot of the lights in a string:

Turns out, the lights were a bunch of SpaceX satellites catching the sun's rays and making them appear like an invading fleet of alien warships.

Elon Musk's company had just launched 60 of the things into orbit on Feb. 15, which orbit 60x closer than most satellites, making them quite a bit more visible.

The reason? Those satellites are part of SpaceX's plan to bring satellite broadband to nearly everywhere on the planet. That requires a lot of satellites and a lower orbit.

This is what that network will eventually look like:

And here's a video of a similar sighting last year after a previous launch:

The company is planning to change the angle of the satellites to keep them from being as visible from the ground below. Rocket science is pretty cool.