"For The World Is Hollow And I Have Touched The Sky"

http://www.startrek.com/database_article/yonada

These are, of course, famous last words. Sometimes, discovering that you are on a generation ship can be bad news - for you! It certainly was for the old man who in his youth had touched the sky of the shellworld generation ship, Yonada. The computer known as the Oracle killed the old man for revealing what he had learned: that the world was hollow, and he had touched the sky.

The Oracle is the caretaker of Yonada. It has the ability to speak to the people of Yonada when they are present within its Oracle Chamber. Its face is the stone monolith with the gold star symbol (see the image, below). The Oracle also communicates the will of The Creators  through its intermediary, the High Priestess of The People, Natira.

Oracle Room
http://www.flickriver.com/photos/fadmvulcan/3101888786/

Of course, we all know now that if you push the small button in the center of the star image, the monolith moves forward and reveals an accessway into the control bridge of the space ark. But this is more than just an Oz-like Big Reveal (although it very much is that!) because the crew of the Enterprise really need to find the control room of the ship. One of its thrusters is firing under capacity and the ship is off course. In less than a year, Yonada will collide with a Federation world. The world ship is on a collision course with Daran V, which has 3.724 million inhabitants, according to Memory Alpha.

Yonada was built by the ancient Fabrini when they realized that their world's sun was about to go nova. The space ark has been in transit for 10,000 years. During the last years of that doomed planet Fabrina, the people lived underground to protect themselves from their unstable and doomed sun. It is perhaps not surprising then that the religious icon of the Oracle is a multi-limbed sunburst.

http://en.memory-alpha.org/wiki/
Fabrina_solar_system?file=Book_of_the_People_contents.jpg

The Fabrini built a generation ship that enabled their people to continue with a semblance of life on their home world. The good news is that the underground existence of the Yonadans actually looks very comfortable and relatively abundant. However, there are many rules to observe here, most of which are framed as religious precepts.

The presence of swords on Yonada, and particularly in Natira's personal retinue, is less likely due to the existence of cultural, political, and resource conflicts, and most likely due to the fact that the High Priestess has many religious rules to enforce.

Natira, High Priestess of The People
http://en.memory-alpha.org/wiki/Natira

http://en.memory-alpha.org/wiki/Instrument_of_obedience

For example, it is mentioned that only the High Priestess of The People gets to choose her mate. Presumably that is because the computer that runs Yonada, in its religious guise as the Oracle, uses advanced population genetics modeling to make reproductive/marriage decisions for everyone else on the ship. The star-shaped Instrument of Obedience can't directly enforce marriage decrees. That requires someone who will if necessary forcibly move a person from one set of quarters to another.

So we apparently have arranged marriage. But is this all bad?

Here in the West, we consider any infringement on individuals' personal freedom and autonomy to be nearly a metaphysical evil. But on a generation ship with a limited gene pool, this kind of reproductive control is likely to be a necessity. While it is a bit implausible that medical geniuses like the Fabrini did not develop technologies that would have mitigated population staleness and concentration of lethal genes, perhaps they felt that simpler systems such as religious edicts were easier to sustain over thousands of years. Who knows?

One thing we did figure out from watching the episode twice this past weekend: it is easy to imagine that many of the early High Priestesses knew they were indeed on a generation ship. By guess is that they lived in quarters on the upstairs level of the space ark's control room. (We see Spock walk up these stairs to manually adjust the controls of the malfunctioning thruster.)

The High Priestess could have appeared in the Oracle Chamber as either a holographic projection, or - even more mysteriously - physically appeared as if from nowhere in the Oracle Chamber just prior to times of worship and religious decree-making. Perhaps it was only later that the High Priestess came to live completely within the midst of The People. There could be quite a story here.