Vulcan (Invasion of the Daleks)

Vulcan was a planet which supported a Human colony. Though it possessed an atmosophere breathable by Humans it had no known native life forms. It did have pools of fuming mercury.


 * ''19th century and 20th century astronomers had believed that the Sol system that a planet, further in than even Mercury, might exist in the Sol system. Possibly, then astronomers would later name Vulcan after a new Sol system planet based on this.

The Human colony was almost taken over by Daleks who had been reactivated by a scientist called Lesterson after being found in a crashed space rocket. (DW: The Power of the Daleks)