In my other topic I asked if there is some kind of story objective planned for the game, other than conquering of entire space.

Settlers Faction:
you support the faction who want to stay in the system and make it more suitable for live. As the planets are barren and terraforming them would take tousands of year, this faction decided to go for space colonization.
The story of this faction would be to build prototype stations that offen more and more space for people as well as better living conditions.

Mission one - provide resources for upgrades of several habitat stations.
Mission two - you are contracted to help in constrution of new prototype station in Nema's orbit - Stanford Torus. You would have two tasks - provide resources for station construction as well as help in protection of build site from pirates and Homecoming Faction.
https://en.wikipedia.org/wiki/Stanford_torus
Mission three - With the success of Torus construction even bigger station is planned in the orbit of Anka. Bernal Sphere (current sphere shipyard station in Blue Heart looks similar, would just need some additional parts).
https://en.wikipedia.org/wiki/Bernal_sphere
Same as with Torus you gather resources and protect the construction site.

Settlers faction final mision -Construction of O'Niell cylinder - station that can provide enough space and Earth-like life quality for the entire population.
https://en.wikipedia.org/wiki/O%27Neill_cylinder

<Open ending> You continue playing and you can even start the Homecoming faction story after you finished this.


Homecoming faction:
This faction is the people who want to return back to Earth. Their aim is to gather enough resources for building of a new return ship ans well as resources for a journey. This story line is less resources gathering (but still you need a lot of them) and more action oriented.

Mission one - you are contracted by Homecoming faction to perform scans of the wreck of original Colony ship that is now controled by pirates.
Mission two - you are asked to help with construction of a huge shipyard that will be used for construction of Return Ship.
Mission three - You have many task for this mission. Provide resources for the ship construction, protect the build site and ferry various VIP experts that are needed with station construction.
Mission four - with ship constructed you need to help with providing the supplied for the journey as well as ferry the people who want to leave to the Return ship. In the same time you need to protect Return ship from attack by Pirates and Settlers faction.

Once ship will be ready to depart you can choose:
<You stay> Open ending, you can continue to play and even help Settlers faction if you haven't done it yet.
<You board the Return ship> Clodes ending, you decide to fly back to Earth. Game Ends.