On Mars, the Mars Probe 13 astronauts accidentally wandered into the city of the Argyre Clan Ice Warriors and were slaughtered after they spied on a research facility. To appease the Ice Warriors, the British government's representative, Minister Edward Greyhaven, had mission commander Alexander Christian framed for the astronauts' deaths and imprisoned. He agreed to ensure humanity would not return to Mars. For the next two decades, the British Secret Service spread disinformation that Mars was uninhabitable and sabotaged NASA data in order to discourage Mars missions. In actual fact, Mars' atmosphere was breathable. (PROSE: The Dying Days)
Behind the scenes
The Mars Probe missions are ignored by the Doctor Who television story The Waters of Mars, which referred to the human colony founded in 2058 as being made up of the "very first humans on Mars". Further complicating matters, an on-screen obituary in The Waters of Mars mentions that the captain of the Bowie Base One colony, Adelaide Brooke, along with two other unidentified astronauts, had already landed on Mars when Adelaide was 42 in the year 2041. The Waters of Mars clearly shows the planet as being inhospitable and uninhabitable in the 21st century, with a breach in the hull of the colony sucking air out into a vacuum. The Tenth Doctor also mentions that a flower in Bowie Base One's bio-dome was the "first flower on Mars in ten thousand years", and describes the Ice Warriors as "legends... from long ago". In the television story Empress of Mars, set in 1881, the Twelfth Doctor explains to Iraxxa that Mars' atmosphere has "all but evaporated", the surface is "lifeless", and any other Martians who may be hibernating cannot survive without help.