In 2050, due to the global warming, the sea level will rise sharply, many coastal cities will be submerged, and there will be less and less land for human survival.
As the sea level continues to rise, scientists predict that by 2100, all of the earths land will be submerged by sea water, and the earth will become a mercury star.
Alien immigration is imminent, and Mars, 55,000 kilometers away from the earth, has become the last hope of human homeland.
Fortunately, as early as 2022, some forward-looking humans have already begun such a great plan.