Sentarion

Sentarion was a desert planet. It was known for its universities and scholarship.

Astronomical Data
Sentarion orbited a star that was larger than Earth's and orbited it more closely, making it very hot. It was smaller than Earth and had a richer atmosphere; insects grew to greater sizes. Crystalline rocks found on the planet could be used for solar-energy panels.

Sentarion was largely uninhabited, though there were several species of intelligent insects on the planet. Known species included the Sentarii (the rulers), the Harrubtii (the religious zealots), a grasshopper-like species (the middlemen) and a beetle-like species (the labourers). There were also great variations within these castes. (NA: Shakedown)

Culture
Though there were several species of insects on the planet, they tended to share a similar culture.

The inhabitants of Sentarion were pacifists, except for the Harrubtii. They led simple lives, focused on the pursuit of knowledge. They had vegetarian diets, opposed the drinking of alcohol and had few comforts in their dwellings. They didn't socialise with others, working during the day and sleeping during the night. Despite this, they weren't opposed to aliens doing otherwise.

The insects of Sentarion were a religious people, especially the Harrubtii. They worshipped the Shining Ones, who were actually the Rutans. Most discussion on the Rutans was taboo, sometimes leading to death by the Harrubtii. (NA: Shakedown)

History
Early in their history, the insects of Sentarions fought endlessly with each other. At one point, the Rutan Host arrived on the planet through a wormhole. They intended to use the planet as an escape route and so modified the native species, making them intelligent and loyal to the Rutans. The Rutans were known as the Shining Ones and were worshipped as gods. Though the Rutans eventually left the planet, they made the Sacred Compact with the Sentarii. If the pact was fulfilled, the Rutans would return one day.

The insects of Sentarion used the knowledge they were given and developed technology, such as the ornithopters which they used as vehicles. Unlike many such civilisations, they skipped polluting energy sources like oil and used solar powered-based electricity. The villages grew and expanded until they formed the massive University of Sentarion. They soon became renowned as scholars and intellectuals.

At some point in the 26th century, Bernice Summerfield came to Sentarion, looking for information on the Rutans. The Harrubtii constantly dogged her, but she was able to find the connection between their planet and the Rutans. When she went into the sacred Temple of the Shining Ones, she was trapped; she would be killed for her blasphemy but her death would foul the temple. When Karne arrived on the planet, he tried to open the wormhole above the planet. He was followed closely by the Seventh Doctor and his allies, and then by Commander Steg. Commander Steg forced the Doctor to open the wormhole and sent a War-Wheel to Ruta III to kill the Rutan Queen. The Doctor was able to reverse the polarity of wormhole, meaning the War-Wheel would never leave the wormhole. The wormhole was sealed permanently. (NA: Shakedown)