[@Emma] Cool. Ok, so some questions:

[list]
[*] So are the space stations stationary? The Human race seems to be looking for a new Earth, where are the stations now? 
[*] And who are the other Alien species and why aren't they able to send us in the right direction for a planet to call home?
[*] Is Station 5 one of the places the elites/wealthy of Earth went to or was it one designated for those last humans/their donated progeny?
[*] If the elites are there, is the same disparity still present on the station? 
[*] Are the stations still in contact with each other?
[*] (not really a question) I feel like 20 years might be unrealistic amount of time to build a bunch of space stations capable of housing millions of people, unless they were already nearing completion when humans realised how dire their situation was and were re-purposed.
[/list]

I'll leave it there for now, but I'll probably have more :)