Satellite Five
Satellite Five was a space station in Earth orbit circa the year 199,909.
Physical structure
It had a central cylindrical structure ringed by three hoops. The purpose of the hoops could be to provide an artificial gravity field allowing the Satellite to be habitable by humans. Satellite Five was 501 floors tall. Assuming a regulation floor height shown onscreen as five meters, and giving approximately two 'floors' on each terminus of the central cylinder for the 'caps' seen, this gives the Station a total height of 2,525 meters without the (unknown) hull thickness.
At least during the Doctor's first visit there, Floor 000 served as arrivals and departures. Floor 016 was the surgical level. Floor 500 was the editorial level, where management is based, and the place to which everyone aspires to be promoted. The walls were rumoured to be made of gold, but in reality, it was very different: cold, abandoned and dilapidated. (DW: The Long Game) In 200,100, the same area served as a command center for the Controller. On this level were a number of archives, including Archive 6 where the TARDIS was kept (DW: Bad Wolf, The Parting of the Ways). Other floor's, for example, floor 139, contained a food court which was
visited by the Doctor, Rose Tyler and Adam Mitchell in the year 200,000 which served junk food much to the confusion of the Doctor who believed humanity had 'fine food' in this era.
Each floor on Satellite Five seems to consist of a large room where the elevators lead off, with many other rooms situated on the side of that floor. The large rooms on each floor seem to be significantly smaller in the year 200,100. This could be due to the Satellite being converted into the Game Station which requires more space for the game shows.
History
Satellite Five (199,909 - 200,000)
Satellite Five went online in 199,909 during the Fourth Great and Bountiful Human Empire. It was responsible for broadcasting 600 channels of constant news reports throughout the Empire. Personnel gathered, wrote, packaged and sold the news, sorted using brain chip technology.
In the year 200,000, the Doctor, Rose and Adam materialised on floor 139 and discovered that humanity was being manipulated by an unknown source. They discovered that the Jagrafess was subtly manipulating the Empire, changing its social, economic and technological growth and making it more inward-looking and xenophobic. In this way, the Human race has been reduced to slavery without them even realising it.
The environmental systems of Satellite Five had been configured to vent all heat away from Floor 500, keeping it cold enough for the Jagrafess to survive, attached to the ceiling of the main control room. Ultimately captured by the Editor and about to be killed by the Jagrafess, the Doctor and Rose were saved by Cathica Santini Khadeni, a human journalist who reversed the environmental systems. The Jagrafess overheated, swelled up and exploded. (DW: The Long Game) But the slavery of humanity still continued.
Game Station (200,000 - 200,100)
100 years after, Satellite Five had become the Game Station. Run by the Bad Wolf Corporation and overseen by the Controller, it broadcasted game shows and reality TV. The contestants were not volunteers, and anyone could be chosen at any time. The shows included a version of the Big Brother House on Channel 44,000, The Weakest Link, What Not to Wear, Call My Bluff, Countdown, Stars in Their Eyes, Ground Force, Bear With Me, and Wipeout. If the contestants failed, they were, supposedly, disintegrated.
The Doctor, Rose and Jack woke up to find themselves on board the Game Station. The Doctor had been transported to a future version of Big Brother, Rose was forced to play a deadly version of the Weakest Link and Jack appeared in a 2001st-century version of What Not to Wear. Upon escaping, the Doctor discovered that the Daleks had been controlling humanity. They had been hiding their own transmissions within the Game Station signals - and before that, Satellite Five's transmissions, controlled for them by the Jagrafess. It was from this point that the Battle of the Game Station began. The Daleks were finally destroyed when Rose, having made contact with the heart of the TARDIS and transformed herself into the Bad Wolf entity, turned every last Dalek in existence to dust including their Emperor. (DW: Bad Wolf, The Parting of the Ways, Children in Need Special)