The Sun

Sol or the Sun was the home star of the solar system, a planetary system about twenty-seven thousand light years from the galactic centre of Mutter's Spiral.

History
The First Doctor was unfamiliar with Sol prior to his departure on Gallifrey. However, his granddaughter Susan Foreman learned of the existence of the solar system and Earth in her spacial cartography system. (AUDIO: The Beginning)

Human scientists predicted solar flare activity would sterilise their homeworld of Earth and took measures to prepare for it. To this end, they left Earth in ships, amongst them Starship UK. (TV: The Beast Below) Space Station Nerva may have gone into service as a refuge for humans and other life in cryogenic suspension. (TV: The Ark in Space)

In the 57th segment of Time the last humans left on Earth evacuated the planet because of the increasing danger that it would fall into the Sun. They fled to planets such as Refusis II and Frontios. (TV: The Ark, Frontios) The now uninhabited Earth was preserved by the National Trust and over the billions of years following was restored to a "classic Earth" before it was finally destroyed by the expanding sun in the year 5.5/Apple/26. (TV: The End of the World)

Cultural and religious significance
In 100,000 BC a tribe of early humans worshipped Sol as Orb. (TV: An Unearthly Child)

In Mexico circa the 15th century, the timing of a solar eclipse had great religious significance. (TV: The Aztecs)

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