There's some tiny agency within whatever galactic superpower it is which preserves planets as historical sites. There's some kind of machine that magically prevents the sun from going supernova, which is operated by all of one guy and a handful of oompa loompa. It's supposed to be some kind of comically absurd penny-pinching bureaucratic bullshit, but obviously they don't go into any detail because Doctor Who is softer sci-fi than fucking Megas XLR.