Writing " . . . from the real world" articles
Planets from the real world is a member of a category that organizes things within Doctor Who universe. As such it (or, if a subcategory, articles within it) must be written from that point of view. Care must be taken with articles or subcategories like this to ensure that we stress only what is known within the DWU.
Main body of article
Please remember that the main parts of articles within a DWU category should only give information that is actually provided in the story or stories concerned. For instance, an article about a song from the real world shouldn't state the writers of that song, its highest UK chart position or, generally, the year in which it debuted. Almost never is such information provided in a DWU source. Likewise, people from the real world usually are not given full birth and death dates or detailed career information in a DWU story. We don't know from a DWU source, for instance, even what the dates of Margaret Thatcher's prime ministership were. They could be different from that which obtained in the real world, especially given the presence of strictly fictional prime ministers, like Harriet Jones. While copying Wikipedia articles is not forbidden by our Manual of Style, it should be strictly avoided for subjects within the " . . . from the real world" categories. Limit yourself to only that information which can be seen or heard from the story concerned. Remember, all these articles will have a wikipediainfo link, anyway, allowing readers to easily access Wikipedia, if they so choose.