if you haven't seen this anime, its called gargantia and its about a race of humans that live in outerspace and fight an alien race called the hideauze.
the hideauze, are basically alien squid/octopus, but during the battle they have to retreat, while trying to escape through the worm hole two soldiers were attacked, with the hideauze attached to their yunboro, in order to defeat them they had to blow them up but in doing so it caused a malfunction in the worm hole and it sent the to a different galaxy, they find themselves on a planet thought to incapable of sustaining life, Earth!
there the main character, ledo, meets humans but earth isn't how he thought it would be. here he learns about earth's past and even the origin to hidaeuze. it sucks this only has one season, I just finished this and I loved it ! I didn't want to stop watching it, but for any who have seen it, what are you thoughts?