In the year of 2158 the human race was faced with humanity biggest fear, Overpopulation. it was around 47 billion human and it was a disaster .But by the time human race have changed from planetary species into interstellar species. They have conquered the sun solar system and have make use of other planet resources such as mars's iron dust and Jupiter's helium.
The government of the world decided the earth was no longer inhabitable. So They've come up with a solution that is to leave the sun solarsystem and migrate to another solar system in the milky way galaxy, using the sun solar system resources they created seven massive one-way transportation systen to move out 42 billion human race with six destination and leave five billion human that is unable to pay the cheap price at the sun solar system.