The Rift Galaxy is an unbarred, flocculent spiral galaxy made up of two smaller barred spiral galaxies colliding with each other located 109 million light-years away from the Milky Way. It was formally the seventh satellite galaxy of the Libation Galaxy in the Thavma Cluster.
Known by the official numeric designation NGC 6889 by the Confederacy. It would later be named the Rift Galaxy due to the galaxy's current nature. It used to be, or maybe continues to be, the home to 26 billion stars and countless lifeforms, before they're extermination.
Its main occupants were the Faded, an ancient Late Type 3 species that made liberal use of time travel in their home galaxy that existed from 7,000,000,000 BCE to 1000 CE. Ironically, this use of time travel would end their known existence.
Now, the galaxy exists in a rift in space time, making it exist in a different dimension then the one our universe occupies. The reason of this is due to the actions of the Faded. To combat an invasion from a yet unknown force from their parent galaxy, Libation, and instead of fighting back, they opted to go back in time a prevent the formation of the Libation Galaxy entirely. However, this caused a ripple in space time around their home galaxy, leaving it stuck in between to points in time. So while the galaxy's visible light can be seen from millions of light years out, or even as close as possible, it's not really there in our plane of existence, making it impossible to enter.
It remains unknown as to what exactly happened to the Rift Galaxy and the Faded but theories abound exist.
The geography of the galaxy can be split up in two parts.
The first part is referred to as the Pre-Fade. The Pre-Fade is one of two smaller barred spiral satellite galaxies that collided to form the Rift Galaxy and is the larger of the two.
While the second part is referred to as the Fade, as it was the second of the smaller satellite galaxies that contained the Fade and is the smaller of the two.
In 5,600,000,000 BCE, two smaller satellite galaxies of the Libation Galaxy, nicknamed the Pre-Fade Galaxy, and the Fade Galaxy respectively, slowly came closer together due to gravity. This ultimately culminated in 4,500,000,000 BCE, when the two galaxies collided with each other, forming the Rift Galaxy.
As they did, the native Faded of the Fade Galaxy began to use their temporal technology to quickly prevent all life in the Pre-Fade galaxy from ever arising in the first place, much alike they had done to their home galaxy.
The Faded would continue to be the only inhabitants of the Rift Galaxy, until' yet unknown invaders entered within it from the Libation Galaxy in 1000 CE. And since the Faded had little hope of fighting back this powerful force, they attempted to preform the largest feat of time travel in the known universe at the time, as they tired to somehow prevent the formation of the Libation Galaxy in its entirety. However, this somehow caused a temporal cascade effect across their entire galaxy, leaving it stuck in between to points of time, while not being in either at the same time.