Justicia

Justicia is a solar system which is used as a massive prison.

History
Justicia was originally formed to store alien criminals, but due to overcrowding amongst the EarthGov colonies, Human criminals were also sent to Justicia.

Around the 2500s, the Blathereen discovered another use for Justicia. The position of its planets made it suitable for warp-holes, which they could use to transport the entire system and use the suns as means to destroy planets, giving them a supply of spaceship fuel. They slowly replaced people of power and lead the research section of Justice Gamma to figure out the necessary math. In 2501, the Doctor and Rose arrived on Justice Alpha and were arrested. The Doctor's skills meant the project could be pushed forward, but the meddling of the Doctor, Rose and three Slitheen lead to the eventual failure of the project and the destruction of the Blathereen criminal empire. (NDA: The Monsters Inside)

Astronomy
Justicia is located near the edge of the Mutter's Spiral, far away from Earth. There are auto-beacons warning all ships which come within two light years and a deflection barrier which extends 10 billion miles. It has three suns and 6 planets with nearly circular orbits. (NDA: The Monsters Inside)

Justice Alpha
Justice Alpha is a muddy planet with a green sky. It is smaller and has a lower gravity then Earth. It was used for historical re-enactments, such as pyramid building. Justice Alpha is 100 million miles from the suns. This is the first planet on which Rose and The Doctor arrive, and where they are captured. The Blathereen planned to store the processed fuel here.

Justice Beta
Justice Beta is covered in greenish marshes and prisons. These prisons are low-tech as a test and are used for Human criminals, specifically juvenile delinquents. It is 150 million miles from the suns. This is where Rose is sent after being captured on Justice Alpha. The Blathereen planned to use it for breeding stock.

Justice Gamma
Justice Gamma has a Middle Eastern jail colony where Human prisoners are kept. They had a wide variety of experiments done on them. It is 200 million miles from the suns. The Blathereen planned to use this planet for heavy labour.

Justice Delta
Justice Delta is a forested planet with a green sky. The Executives lived on Justicia Delta and controlled Justicia from there. Ecktosa and Dram were both caught here trying to find the antique Compression fields. It was taken over by the Blathereen during the plot and used as a home base.

Justice Epsilon
Justice Epsilon had acid plantations. Dennel's father was sent here for bank robbery. The Blathereen planned to use this planet for processing the remains of the destroyed planets.

Justice Prime
Justice Prime is a small cold planet, so cold that the nitrogen on the surface is turned into snow as it moves away from the sun. This is the only planet in the Justicia system which didn't have a circular orbit. This planet was the first to be used as a prison planet, specifically for alien criminals. The alien criminals are kept underground in the SCAT-house (Species-lead, Creative and Advanced Technologies). This is where the Doctor was sent after being captured on Justice Alpha.