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Also known as the Galactic Atlantis, this temperate temperate terra was a mythical lost human colony that was rediscovered in 29991. It orbits the star of a quadruple star system.

Popular Culture

Before its rediscovery, Gatlantis was a great mystery. Many theorized about its location, as well as its supposed advanced tech. There were many science fiction stories and shows made depicting the supposed culture of the settlers of Gatlantis.

The sci-fi holonovel When Worlds Collide is the most famous fictional work set on Gatlantis, depicting a hyper advanced civilization on the edge of the Via Lacrimosa who have made contact with a number of other civilizations including the First Civilization. It spawned a number of sequels along with a holoseries based off of the book.


Historic first image

According to the logs of the ancient colony ships located on one of the moons of Gatlantis, the original colonists left at the height of the Eastern Galactic Rebellions. They were a group of extremely intelligent scientists and pioneers who were tired of war and their ideas used for destruction.

Fearing that the Yohjan Confederacy was doomed to be destroyed and that a new Dark Age was coming, they built massive ships in secret and installed prototype Warp Drives that could travel faster than those of the time. They had discovered a planet perfect for human life a very long distance away from the core worlds. With their new drives it would take the colonists fifty years to get there. The technological equivalent of their Warp Drive wouldn’t be invented for another thousand years.

When they reached the planet five decades later, they found that life already existed on the planet, but only in the form of small plankton-like life in the seas and a green mosslike substance on the land. The colonists first had to introduced terrestrial life to the planet and after another twenty five years the planet was transformed into a paradise where humans could live. The colonists dismantled all but one of their ships and left it on the closer of the two Selena-Class moons to keep a watchful eye on their history and on the skies in case future humans found them.

The current population as of a 99995 census is 1.2 billion.


When the first colonists first settled the planet they built metallic but primitive structures. They had a philosophy of simplicity and not relying too much on technology.

After living like this for thousands of years, a rift began forming between a group that wanted to build a more advanced society and a group wishing to keep themselves more simplistic. Not able to find common ground the groups split. The former group headed north across the mountains and ice near the equator and to the fertile grounds of the north. They built a vast technological civilization across the north.

In the south things remained the same. Occasionally people who were dissatisfied by either side would travel to the other human civilizations where they would give the alternate lifestyle a go.


Current map of Gatlantis

With a steep axial tilt of 117°, the planet has incredibly wild seasons that the original teraraformers took into account when bioengineering the plants and animals. Because of this, the equatorial regions are mostly ice and snow while the poles remain snow free. The planet has a current mean temperature of 4.8 °C. It has a nitrogen oxygen atmosphere with a pressure of 0.8 ATM at sea level.

Most animals are very migratory, migrating during the seasons to find a place where there is a night and day cycle.

Currently, however, a terraforming company is working on the planet to alter its tilt so that the planet can warm up and become more habitable after getting permission from the humans of Gatlantis.