Terra

By 2100, a base on the moon became firmly established, whilst the economy on Terra improved.

Bioremediation and environmental engineering of Terra saved that planet from pollution and desertification.

Soon enough, there were only three enormous countries on Terra.

Soon enough, countries splintered all over Terra to create over a thousand small countries.

It took generations to iron out all the problems of human pregnancy and child rearing outside of Terra.

Taking risks may land you on terra incognita and make you long to plant your feet back on terra firma.

Luna declared independence from Terra in the year 2231.

Mars declared independence from Terra in the year 2302.

During the First Solar System War, the expanse divided itself into the Inner Alliance and the Outer Alliance. Terra, Luna, and Mars were members of the former. The Jovian moons and Saturnian moons and beyond towards the periphery were members of the latter. The war lasted four years. It heavily devastated Terra and culminated in the surrender of the Inner Alliance.

"Here in the Imperial Martian Garden, we have tropical plants, as well as temperate-climate plants, from Terra." "Doctor Kanda, it's so beautiful!"