Fictional depictions of Mercury, the innermost planet of the Solar System, have gone through three distinct phases. Before much was known about the planet, it received scant attention. Later, when it was incorrectly believed that it was tidally locked with the Sun creating a permanent dayside and nightside, stories mainly focused on the conditions of the two sides and the narrow region of permanent twilight between. Since that misconception was dispelled in the 1960s, the planet has again received less attention from fiction writers, and stories have largely concentrated on the harsh environmental conditions that come from the planet's proximity to the Sun.[1]