Mars

Mars is a dying world defined by cold and decay, its frozen deserts and iron-scoured plains haunting the narratives that touch it. Conceived as the Ice Warriors' hollowed homeworld, its unrelenting hostility drove their desperate invasions of other planets, such as the attack on the Moonbase, as they sought to escape the planet's slow collapse. Later, its thin atmosphere and reddish dunes framed human paranoia, as Probe 7 astronauts Frank Michaels and Joe Lefee landed there only to vanish, while Space Control traced the fading signals of lost crews, and Carrington's alien encounter during an earlier probe seeded dread of invisible threats. Within the claustrophobic storeroom of a Martian pyramid, the Doctor and Sarah felt the weight of ancient circuits and the oppressive silence, before the pyramid's sands gave way to Sutekh's unhinged power. Finally, Mars appears as a dull copper disc behind the Trial Chamber, its rust-streaked plains and the scar of Valles Marineris casting a somber glow, indifferent to the machinations of the Hyperion Three’s cargo of Mogarite or the verdict of the Doctor's trial—an unchanging, silent witness to events that have long outgrown it.