Just remember the mysterious story of Pollination In the world of Sims 4, aliens returned to us with the Get to Work expansion pack, and we will soon get.
Aliens were always a big part of the Sims lore.
Aliens in the sims 4 don't appear randomly in the game, in fact, the chances of their appearance are only 10%. Sixam was then changed to a secret lot in The Sims 4: Get To Work where Sims can visit. The planet Sixam was first featured in The Sims 3: Seasons as a text-based adventure which Sims can travel to through the Galaxa Space Car's Space Travel upgrade.