Guinevere One

Guinevere One was a space probe sent from Great Britain to explore Mars in 2006 in order to look for signs of alien life.

Characteristics
Matthew Nicolson helped program Guinevere One. The contained water, wheat seeds, A+ human blood, and recordings of whale song, bird song, music, and spoken greetings in 120 languages. (TV: The Christmas Invasion) Part of its mission, according to an official source, was to collect soil samples, though the fact that it also attempted to communicate with extraterrestrial life, seemed suspicious, at least according to Mickey Smith. (PROSE: Mars)

History
In late 2006, Mickey Smith first saw news about the Guinevere probe on television, but didn't heed much thought to what he assumed was just a simple probe, as he had faced several alien in the past few years. However, after Daffodil contact Mickey and told him to look at the Guinevere website, Mickey became suspicious of the probe, about its true purpose and the involvement of PM Harriet Jones. However, Mickey knew he had to wait to until Christmas Day for news. (PROSE: Mars)

On Christmas Eve 2006, it was intercepted by a Sycorax spaceship, and therefore never reached its destination. (TV: The Christmas Invasion) Sgt Catherine Petts reported it had gone missing, on an operations board on a secure part of the UNIT website, however Sgt A. Frederick, who had contacted Llewellyn, had been told that it was merely had something to do with a "momentary signal failure" and an "orbital window", though she noted that Llewellyn had the "rabbit-in-big-scary-headlights" look. (PROSE: Guinevere One) The Sycorax, who had hijacked the probe, transmitted a message to Earth, threatening to kill two billion people, a third of the population, via using A+ blood with their blood control. (TV: The Christmas Invasion, PROSE: The Christmas Invasion)

Behind the scenes

 * Part of the inspiration for Guinevere One came from the failed real world British probe, which would have landed on Mars in December 2003. However, the probe itself is a virtual copy of the NASA Magellan Mission to Venus.
 * The probe is described as Britain's first mission to Mars. This contradicts the events of TV: The Ambassadors of Death, which referred to a manned British mission to Mars during the UNIT era.
 * BBC Wales Graphics spelled the probe's name in different ways throughout the episode. On some screens, it appears as "Guinivere One," much to the chagrin of Russell T Davies and Julie Gardner in the in-vision commentary to The Christmas Invasion on the series 2 DVD boxset.
 * In Russell T Davies' 2019 show , a news headline mentions the "Guinevere Probe in major alert".