Given the distance between the planets, these are not aliens, these are immigrants.
If Aliens were to find us in search of an intelligent (hate this word) life, they might have come to the conclusion that the life are our cellphones and we are just the robots taking care of them.
Given the distance between the planets and the unhospitable conditions for human beings on many of them, we might send self- and non-self-procreating robots to other planets and teach them to make do with whatever there is. If we can somehow solve the problem of the speed of information transfer, we can embody the robots over there and literally carry on living over there. Which kinda creates a concern: are we the robots self-created on earth controlled from elsewhere? Well, to be realistic, this thought has to assume that we get just a few commands and the rest we handle ourselves. But that can be easily resolved by assuming that the aliens controlling us live way longer.
