Great entry! I loved the little intro sequence. The gameplay itself is simple, but complete. I enjoyed having to dodge debris while trying to beam people up. Also fun twist on the typical 'aliens invading earth' trope, where it's now aliens saving earth!
One thing that bothered me a little though was the collider for the tractor beam. It seemed like only the bottom of the beam actually allows you to suck people up, while I would expect the whole length of the beam to be a collider. The humans in building were also hard to see due to the lack of contrast with the background. Perhaps an outline could help visibility.
Overall though, fun simple game. Great job!