Ossus
Most planets in the galaxy were normal. Most planets orbited around a single star thereby making the lives of everyone involved easy. One could easily match up planet and star and catalogue other planets and satellites in relation to the star in question. However, occasionally you ran into a binary star, and sometimes these stars had their own planets. These made the lives of astronomers difficult as calculating the orbit of a planet around two centers of mass was impossible to perform with precision, a mathematical irregularity that became known as the Three Body Problem. However, most of the time the planet cooperated by orbiting around both stars in a wide orbit.
The planet Ossus in the Adega system did not cooperate. It orbited in a figure eight pattern between the binary stars. A planet with such an orbit would be impossible in any sane universe, but not only did the planet Ossus exist, but it had once been teaming with life. To further add to the gravitational nightmare, Ossus had a large moon named Nerit. This moon was so large that many people considered 'Ossus' to part of a double planet system together with its moon. Stranger still, Nerit was one of the only known moons in the galaxy that was more massive than it's primary planet, that is to say, Ossus was large in diameter, but Nerit was more massive. This oddity caused Ossus to orbit around Nerit even more than Nerit orbited around Ossus despite their relative sizes. This mass difference was caused by Ossus being large but having a mantle and crust composed mostly of light elements with very few metals. On the contrary, Nerit was full of dense metals and hyperbarides with a molten lead and uranium core. Nerit's mass caused it to be more heavily affected by the gravitational tides of the two suns whereas Ossus was relatively stable thanks to its more flexible composition. As such, due to these tidal forces and radioactive decay in Nerit's core, the surface of Nerit was a hellish volcanic landscape with a few temperate and fertile plateaus here and there.
The Intergalactic Union of Astronomers was at a loss when it came to explaining such phenomena. The leading hypothesis was that the system was constructed by a race of ancient aliens, most likely the Celestials.
Now while the Celestials were infamous for being the subject of almost as many crazy crackpot ancient alien theories as there are crazy crackpot ancient alien theorists, the Intergalactic Union of Astronomers was not stupid. They were scientific and believed that if an extraordinary claim had extraordinary evidence, they should at least consider it. As to the Adegan system, it was ironically much easier to explain the phenomena by appealing to ancient aliens that it was to appeal to natural causes- a situation which provoked considerable methodological fights as to what counted as a valid scientific theory.
Rey however did not have any of these scholarly concerns on her mind. She sat cross legged on the bedroom floor as she tried to get in touch with the Living Force, but it was elusive. Ever since the death of Luke Skywalker it had not come easy to her. But then again, maybe it never came easily to her. After all, she went from not even knowing she was Force-sensitive to being able to levitate large mounds of stones in about a week. Perhaps it was a fluke. Perhaps the strong Force nexus present on Ahth-to had given her the clarity needed to connect to the Force or perhaps it was the presence of Luke Skywalker himself, but in any event she could now barely feel the Force. It was still there, she could at least feel it that much, but it was distant and elusive, like a distant echo or a twinkling star.
The ship rocked and she gave up. She rose to her feet and walked over into the cockpit of the Millennium Falcon where she found HK-47 trying to guide the ship through the turbulent planetary atmosphere. Strangely enough, there was little moisture at this elevation, but the ship was rocking from side to side.
"Cautious Greeting: Please do not touch anything, master," said the droid, "The upper atmosphere of Ossus has very high winds due to gravitational tidal forces from its two suns and primary moon. I would rather not be disassembled in a fiery crash."
"How is there this much wind up here if there are no storms?" asked Rey "Back on Jakku the winds usually only picked up in a sandstorm."
"Annoyed response: Master, do I look like a weather droid to you? Besides we are at too high of an altitude for storms and every planet has different climate patterns."
Rey didn't respond. The ship continued to descend for several minutes.
"Do you know where to land?" Rey asked at last.
"Reply: Master Luke and I came here several years ago. I will land where he landed."
After several minutes the ship descended beneath the planet's upper atmosphere, and the ride became much smoother. Apparently the hurricane force winds were only an issue in the upper layers of the atmosphere. For the next few miles, the ship fell with it's repulsor engines on to come to a slow and controlled glide down. Eventually, the landing gear deployed and the Falcon touched down.
Looking out the transparisteel cockpit windows, Rey could tell that it was around the middle of the day. The large ruins cast long shadows despite the sun being high, a testament to their size, and in all other directions the desert stretched until a small ridge of mountains in the distance. Rey checked the scanners. The atmosphere was breathable and there was no harmful contagents. She walked over to the back of the Falcon with HK-47 close behind. She pressed a button and the ramp fell.
Stepping outside, the desert air reminded her of home, and due to the familiar climate, she was wearing her desert robes rather than the clothes that Leia had given her. She wore a small blaster on her waist.
"HK, what was your visit here with Luke like?"
"Nostalgic response: Oh master, it was a pleasant excursion."
"No, I mean where did you go? What did you do? I have no idea how to navigate this planet."
"Resigned response: Fine." The droid pointed at the large structure in front of them and walked over. Rey followed. "These are the remains of the Great Library of the Jedi. At one point it housed the center of the Jedi Order itself- that was around four thousand years ago."
"What happened?"
"Sarcastic response: Oh master, but you're the Jedi, you should know this. Didn't master Luke teach you anything about history?"
"We didn't really have time for that."
"Weary reply: Oh woe is the state of education these days! However will the youth survive if they know nothing? Anyway, around four thousand years ago was the Great Sith War- I assume you know nothing about this right?"
"Not a clue."
"Mocking response: It's almost as if someone retconned the entire history of the Galaxy before the rise of the Empire! Oh how many stories have been lost and are being ignored! Anyhow, the Great Sith War was an event which saw two young and powerful Jedi, named Exar Kun and Ulic Qel-Droma turn to the 'dark side.' They gathered a large band of followers and waged war against the Jedi. Sometime during the conflict, the nearby Cron Cluster was somehow detonated. Since the Cron Cluster is less than a light year away, the radiation blast and supernovae shockwave destroyed Ossus and the surrounding planets."
"Wait, but if the planet Ossus was destroyed in a supernovae, how is it still here?"
"Hesitant reply: I am not sure. The Cron Cluster was a system of ten incredibly small stars. The only reason they were able to detonate is because of the massive gravitational fluctuations caused by ten stars pressed together and because of the lingering gravitational influence of the Adega stars. It's… strange really. My records are sparse but it seems like the Cron System and the Adega system were once regarded as a double system."
"And you said that you have no idea what caused this?"
"Response: Well many historians think that the tidal forces generated by the Adega stars pulled too hard on the Cron Cluster causing one of its ten stars to be stretched and ripped apart, but some think that the Sith had something to do with it."
"You mean they had a weapon that could destroy an entire star system?" asked Rey remembering her nightmares about the Hosnian Cataclysm.
"Hesitant Response: It's possible, but my records seem to be… corrupted."
"Corrupted?"
"Defensive Reply: My memory chips are old. Certain areas have eroded more than others and still more are locked."
Rey thought about this. "Do you think Master Luke could have done this?"
"Admission: I do not know. If someone wiped your memory and placed you on a random planet, you would probably assume that you had simply lived there your entire life. Such things have happened before."
Rey did not like where the conversation was going. "Maybe one day I can look into your memory banks to see if I can repair them."
"Frightened reply: Oh master! Please don't! You'll only make it worse."
"Hey! I'm not that bad with machines!"
"Sardonic comeback: Oh I suppose that being a computer genius is yet another one of your 'skills' that you somehow have despite having no formal training."
"What do you mean?"
"Distracting reply: We should keep going," said HK-47 pointing at the entrance of the ancient library, "When Master Luke first came here the library was sealed up with massive stones. Apparently, some of the natives wished to barricade it. Luke had to use the Force to move the rocks aside."
Rey looked at the the stones that sat before the doorway on either side and marveled at the size of them. They made her own telekinesis she somehow demonstrated on Crait look like child's play. Rey stopped walking and extended her hand. HK-47 watched her curiously. Closing her eyes, Rey reached out with the Force.
The Force sometimes gave one fleeting sensations of the thing being moved, or rather, it was not as if she could physically feel the rock without touching it, but rather it was more as if she could feel the indention or shape of the rock in her mind's eye. She pressed against the rock, applying pressure like she trained to do. She remembered levitating those huge stones on Crait or pulling Luke's lightsaber out of the snow on the Starkiller. Still, somehow the Force was fleeting. She pressed against the rock and became angry that it wouldn't move. She pushed again and again growing more and more frustrated by the second and yet the rock wouldn't move.
She opened her eyes and walked over to examine it. The rock was in the exact same place, but the base appeared to be slightly displaced as if someone had given it a shove to dislodge it from the surrounding mud only to let it drop back. If the rock had moved as a result of her using the Force, it probably only tilted a few centimeters in either direction. Frustrated, Rey pressed against the boulder with her arms and physically pushed it. The rock slowly moved and she was able to roll it out of its indention in the ground and send it rolling about a meter down a small dirt incline.
"Unhelpful encouragement: Very impressive master."
"Let's go," she grumbled walking towards the entrance to the library.