The birth place of humanity, home to the usual nine planets and other celestial bodies. In the centuries of space travel and climate collapse things are a lot different than in the 21st century… for the worse.
Comet mining for ice to break down and gas giant siphoning for fusion material is extremely lucrative.
Where humans came from!
The biosphere collapsed centuries and very little of the classical flora and fauna still exist, mostly in the private zoo collections of the uber wealthy.
Terra is still livable! Entirely because of climate technologies and the poles being functionally livable with little other intervention. The equatorial regions experience near constant massive storms. Outside of the poles people live in the habitable slums around space ports. The further you get from a port the more dangerous living is.
The poles house earths remaining fortunate and wealthy individuals. The Antarctica archipelago has beach resorts, and the northern polar region has regular snowfall due to expensive climate hardware.
After the signing of the Human Domestication treaty the Affini Compact turned their advanced technologies into restoring the earth to its healthy green past. And of course they provided all the cute little terrans with proper homes.
Since the moon can't hold an atmosphere due to solar winds. Everyone lives in dome like structures and underground. Lighter gravity allows for easier space launches which made all the investors prefer it. Without atmospheric super storms and rising oceans to destroy habitable areas Luna's population soared.
The population core of the Terran Accord, Mars like Luna has trouble keeping an atmosphere, but it has been terraformed to have one.
The upper echelons of humanity's elite hang out around the Jovian moons. Private space station homes orbiting near massive settlements on the various moons. Otherwise the Jovian and Saturnian moons are lower population versions of Luna.