Earth, is the most common name for the planet of which Humans evolved on, although it has spawned several sentient species, such as members of the taxonomic rank Order Cetacea. Earth is not very well known outside the Milky Way galaxy but within it seemed to hold historical and mythical significance, although now Earth is sparsely populated and has sank outside political affairs.
Earth has been dated to have formed 4.54 gigayears before modern history, and has retained a linked, dynamical structure between the core, the lower mantle, upper mantle and asthenosphere, lithosphere, life and climate for almost four billion years as plate tectonics started. The abiogenesis of life is thought to have occurred between 3.9 and 4.1 billion years ago. In its history, the Earth is believed to have collided with a Mars sized-object and of course survived. It has entered periods of hothouse climates, as well as colder periods that included ice ages. Some early icehouses encased almost the entire planet in ice (the "Snowball Earth hypothesis"). The links, some being positive feedback cycles are highly complex on Earth, enriched in may subtle ways by the biosphere.
From the traditional Copernican Principle, Earth is just a typical planet of a typical star, of a typical galaxy, of no particular absolute state of rest, and part of the rhythem of meaningless processes running via the laws of physics. While this was true, from a knowledge-based view, Earth is classed as part of a very few planets of every galaxy to bare emergent processes that lead to the evolution of complex life, and emergence of conscious, creative/critical intelligence. That is to say, Earth is an environment that creates knowledge, a hub where one part can understand other parts. Very few places in the universe had yet to evoke meaning out of meaningless elements, by nature.
Earth was rare, space was vast. But the problem solvers from Earth and those other rare earths had something in common, an ability to understand the laws of physics enough to use them. Life from Earth was spread throughout the cosmos, both on purpose and by accident, both by panspermia and by intelligence. Meanwhile, the significance of life was that while small in comparison to the cold and destructive forces of the universe, it was causally significant on emergent scales.
Many myths were told about Earth by its progeny and its visitors, including the myth just told. To humans, it was their home, a place of historical sentiment, or an object of politics and economy. To fewer it was a unique spaceship, or a hub of knowledge creation not so unique but rare by non-design none-the-less, or a superorganism or computational node to be spiritually admired.
The Krassio have visited early human tribes in the past for study, and have deduced that Earth is the metaphorical "centre" of the multiverse. To the Xhodocto, Earth's only significance is that they were unleashed from a monolith which fell on the planet. The Xhodocto have since protected the planet, even during the Annihilation. The Eye is buried on Earth. To the survivors of the Annihilation, Earth is one of the final original beacons of life in the universe, and there is great invest in terraforming life back to devastated colonies using life from Earth.
Sentients of Earth
The first sentient problem solving species to have evolved on Earth were the Alpha Draconians, which left Earth 65 million years ago. In far more recent times sapient life began to evolve again, but in each case the sapience comes in different forms, examples include most famously Homo sapiens, however, their cousins, such as the Neanderthals are considered sapient. The Cetaceans also had evolved their own sentience 20 to 50 million years before. The first and longest lasting sapient species, also unknown to both Dolphin and Human, was the once a global community of sapient plants who's information process worked on the basis of hormones instead of neurons. They could not process information as quickly as their Animalian counterparts, but all this meant their society worked upon longer time scales, and the plants' perspective was normal and the animals were like buzzing insects. This community lasted millenia, slowly following the changes of climate and settling their roots into stabilised environments and shallow basins. Unfortunately, as Humans began to develop agriculture, like an angry flock of vultures this storm ripped through the community too quickly for them to run away (certain plants do actually "walk" and many "creep" in response to barriers), killing millions of its population and severing communities. The species of this community survives, even old members still live isolated from each other, but the civilisation is no more. Younger generations, especially the saplings listen to their elders in awe and disbelief, but none the less listen, while Animalians and Humans buzz around them un-noticeably fast (who consequently, don't notice the incomprehensibly slow actions of the Plant sentience).
Humanity and the Jovar
During the early to middle 21st century, Humans faced several environmental crisis after crisis, for Earth's biosphere was under strain, not neccesarily from just global warming alone. The first major crisis was the near-extinction of bees, creating world starvation and several years of "no Spring", threatening the rest of the food chain. Eventually, it was discovered that the Bees could sense the "6th dimension" and were merely creating a reality without Humans amd were engaging in suicide. Clever considerations were placed to stop the Bees from needing such a reality to live in. After this great shock, Humans began to become more environmentally friendly. Earth was almost hit by Apophis, an asteroid large enough to cause nation-wide damage, luckily missed. After these events, Humans changed their act a bit more before becoming a planetary civilisation.
An unexpected disaster had befallen on the Earth in the 26th century, requiring sudden evacuation from the Sol System. Humans later returned in the 29th century, shortly after the Jovar found it again and resurfaced its significance. The Yamato Stellar Empire made a secret base on the Earth, as did the Ottomans. Very few humans live on Earth today, mostly caretakers who dare walk its surface, and mostly to sample the life for terraforming.
- The Earth was slipping back into an ice age by the 29th century, Neanderthal geoeningeering hastened the effect during Rights of Earth.
- The Earth's pole is believed to be undergoing a geomagnetic reversal by 29th century scientists, but the change would happen very slowly.