Earth, also known by some alien empires as Solria (derived from the name of the planet's solar system, Sol), is the site of the capital of the Republic of Sol and, arguably, the single most politically important place in the galaxy. Together with its only moon, Luna, Earth constitutes the Republican Capital Complex.

The original cradle and homeworld of the human species, Earth has faced many calamities throughout its history, the centuries directly following the start of human Unification Wars proving to be the planet's biggest test yet - mankind, still confined to their home system at that time, engaged in a brutal global war which eventually culminated in widespread, simultaneous nuclear bombardments. Coupled with the re-emergence of global warming and environmental pollution as major problems in the previous years, this catastrophe caused the Earth to become mostly uninhabitable for humans for over a decade while it underwent a harsh nuclear winter. Eventually however, the remaining population of the planet formed a multitude of warring survivor-states which, through conquest and a set of treaties and alliances, eventually unified the globe under a single government - one of the earliest direct predecessors to what is nowadays known as the Republic of Sol. This state would later go on to, through military action, reunify the human species as a whole, confirming Earth's status as the center of human civilisation.

However, even the conclusion of the Unification Wars in 2351 AD did not bring an end to the planet's problems; frequent pirate raids on major urban aglomerations and the extraterrestrial Chirr invasion of Earth in the late 24th century caused further environmental and infrastructural damage, with the alien orbital bombardment alone causing nearly two hundred million deaths planetside over the course of just a few years. With eventual human victory against the Chirr however, came a time of peace and reconstruction. Starting around the year 2400 AD, Earth underwent rapid advancement, going on to become the first true human ecumenopolis on the eve of the 5th millennium.

Nowadays, it can easily be said that of the old Earth, almost nothing remains - its natural crust and much of the mantle has been mined and effectively removed long ago to make space for increasing urbanisation. It is often claimed that all of Earth's citizens live in one and the same building, a monumental urban behemoth of closely connected global megatropolises that covers the entire planet, stretching from roughly 1300 kilometers below the Control Level (Sea Level as it was prior to the Unification Wars) to 13 above it, at which point first open-air streets appear. Even then, however, the highest skyscraper spires reach much further upwards, up to several kilometers, and the planet also hosts billions of citizens aboard massive orbitals and underground "habitats" built deeper into what little remains of Earth's original mantle. This giant arcology, often referred to as "Republic City", contains only three openings - monumental "caves" located at the depth of around Control Level, surrounded on all six sides by metal walls and normally-concealed machinery which supports the massive ecumenopolis. These include the Himalayan Natural Reservoir, the Pyramid Preservation Complex and the Capital District - an opening within the arcology containing the ancient city of Paris, complete with many millennia-old buildings - officially the capital of the Republic of Sol and formally an urban entity separate from the rest of the planet.

In the modern times, Earth is abundant with many technological marvels not found anywhere else in the galaxy. It can without a doubt be called a true testament to the might of humanity and the Republic, but also a reminder of their many mistakes - completely urbanised, the planet is utterly unable to replenish resources even as basic as oxygen without the use of sophisticated generators and interplanetary shipments. In the event of a planetary siege, much of its population would eventually starve or asphyxiate. Similarly, a prolonged failure of the vast life support systems keeping air pressure above Control Level high enough and temperatures near Earth's core low enough for settlement would almost certainly result in the deaths of countless billions. Even things as prosaic as lighting have to be provided artificially for the vast majority of Republic City. Over the millennia, the process of ecumenopolisation had also effectively annihilated all natural habitats of most animal and plant species native to the planet, resulting in their eventual extinction. Preservation efforts and population transfers to specifically-terraformed colonies were of course undertaken, however tens of thousands of species still ended up fading into the annals of obscure history.

Nowadays, the population of the Republic's capital is very diverse, albeit naturally still predominantly human.

Ok what they did to the planet sounds like what is going on now. If it's up to the idiots in DC it will happen.

7961101
The Republic has gone through... many ideological, societal and systemic changes over the course of its existence, as one might expect from a democratic country that is thousands of years old. Throughout all this time, Earth has been one of the only constants, and because of that - as well as being the center of human civilisation - its current state reflect all those different time periods mankind has gone through, and so, both its successes and, well... mistakes. Many mistakes.

There are good things about Earth in the year 6200; it's technologically very advanced, rather developed and human engineering capability can truly be seen on the planet. However, like you said, by that point, these 'positives' probably constitute a significant minority - unless one would actually like to never see actual sunlight over the course of their entire life or revels in the destruction of architectural heritage and animal/plant species, that is!

7961151
So true. I believe that no animal that we have now are still around in this time. Making it most likely genetic engineered pets are all you can find.