Planets of the Hainish Cycle third planet of our solar system. Terrans are descendents of colonists from Hain. At some unspecified date, Terrans join the "League of All Worlds", which includes the Cetians and other peoples of Hainish descent. In "The Left Hand of Darkness", it is said that 'Hainish Normal' people were placed among Terra's own proto-hominid autochthones by the ancient Hainish 'colonizers'. After that initial contact with Hainish civilization Terra experiences two more cycles of isolation followed by the restoration of extraterrestrial contact and community with other worlds. The second period of contact with the interstellar Hainish community is the background for "The
Fictional planets of the Solar System while yet others are purely fictional and were never intended as serious hypotheses about the structure of the Solar System. Vulcan was a hypothetical planet supposed to revolve around the Sun inside the orbit of Mercury, invoked to explain certain irregularities in Mercury's orbit. The planet was proposed as a hypothesis in 1859, and abandoned not later than 1915. The name "Vulcan" has been used for various other fictional planets, in and out of the Solar System, that do not correspond to the hypothetical planet Vulcan. The planet Vulcan in the "Star Trek" franchise, for instance, is specified as orbiting