Tunguska Event

The Tunguska Event referred to the impact of a meteor in the Tunguska province of Russia on 30 June 1908, creating a huge crater.

The "meteor" was, in actuality, half of the TARDIS. It had split in half, then time rammed itself. The energy released by the impact caused the Great Divide to open in Russia, allowing some of the Charrl to enter that time period from 22,000. (PROSE: Birthright)

The Third Doctor attempted to take Liz Shaw and Jo Grant to witness the meteor impact but the TARDIS instead materialised in St Petersburg in December 1916. (PROSE: The Wages of Sin)

After her defection from the Soviet Union to the United Kingdom in 1958, the Czech scientist Dr. Nadia Červenka provided the Sen-Gen Facility with a neuro-chemical hallucinogen developed using a yellow fungus which was discovered in the crater. It was believed to be extraterrestial in origin. (AUDIO: Artificial Intelligence)