The
Aerilon Observatory has been lost for the longest of time. As part of
Aerilon, it is built on top of a mountain and is very hard to reach. The observatory is a one of a kind building, way ahead of its time.
Construction
The observatory was preceded by numerous experiments with hand telescopes and tripod telescopes. Through their magical intuitions, they could iterate and experiment with these items at an incredible pace. But their ambition was bigger, so they built an even bigger telescope. At first, they used levitation magic to use the telescope, but it was clear that they needed a dedicated buillding. Designing the building to support rotation was a big challenge. Getting the necessary resources also proved time-consuming. Because of the thorough designs, the actual construction of the building went really smoothly.
Research
When experimenting with the telescopes, they worked in unison. This made knowledge sharing easy and everybody was kept up to speed about the latest experiments and findings. As a consequence, they didn't really learn how to formulate concepts on paper, as they could just demonstrate the experiment easily.
No obstacle was too big for them to solve. During the night, they would use fireballs as a surrogate sun, so they could continue their experiments with prisms and lenses. The telescopes they made were soon enchanted with powerful spells, like True Sight. During the day, they would cast the spell Darkness in multiple layers in the direction they wanted to look, so that the daylight barely interfered with their research.
Documentation
When they started to look up into the sky through their telescopes, they still had to figure out how to keep track of all the information. Because algebra wasn't invented yet, they had to come up with their own solution.
Most of them wanted to make their research accessible, believing that knowledge should be available to anyone. They decided to make drawings of the orbits. Individuals would take responsibility for a single object in the sky and they would keep track of it meticulously. Others would take this data and combine it into a single drawing of the constellation and how it changed over time. Putting these drawings together, made it decently clear how each object moved.
The designer of the observatory took a different approach and worked on a mechanical computer, which was a big watch with hands for hour, day, month, year and had buttons to fast-forward or fast-rewind in time. Different symbols within the watch would show the position of the sun, planets and moon.
Discovery
The tripod telescopes were perfectly capable of keeping track of the orbit of planets that were close by. The big telescope within the observatory was used to discover new planets within the solar system. Only a few of those could then be tracked with tripod telescopes. The remaining planets had to be tracked using the observatory itself. They decided to work their way out, getting the orbits of the closer planets as detailed as possible, before moving on to bodies further away.
Abandoned
When
The Magic Collapse happened, the research was halted and the observatory abandonded. They understood that the world had fallen into complete disarray and with heavy hearts, they had to admit that continuing the research was a waste of now precious time. The left the observatory and Aerilon in as good a state as they could, neatly packed, doors closed.
Vault
The observatory is locked with a magical test. In the building next to it, there is an explanation about the test. The lock is meant to prevent creatures with limited intelligence and no magical capabilities of entering the building.
The observatory has a vault in it with all of their documentation. Papers with intricate drawings of the internal workings of the telescope, with references to other pages explaining individual lenses. Also included were sketches about operating the telescope or moving it into position. They used pictures, because they assumed people would not speak their language when they'd find this place. They did everything they could, so that those who would find the observatory could theoretically understand and resume their research.
The vault also contains items, like a pocketwatch that shows the time, but also the date and the phase of the moon. The watch is even enchanted with a unique counter-lycanthropy spell, so a cursed person holding the pocketwatch can prevent the transformation by succeeding a charisma saving throw. It also contains a hand telescope with true sight ability.
