Vulcan (hypothetical planet) Vulcan (hypothetical planet) Vulcan is a small hypothetical planet that was proposed to exist in an orbit between Mercury and the Sun. Attempting to explain peculiarities of Mercury's orbit, the 19th-century French mathematician Urbain Le Verrier hypothesized that they were the result of another planet, which he named "Vulcan". A number of reputable investigators became involved in the search for Vulcan, and despite occasional claimed observations, no such planet was ever confirmed. Peculiarities in Mercury's orbit have now been explained by Albert Einstein's theory of general relativity. Searches of data gathered by NASA's two "STEREO" spacecraft have failed to find
Return to the Lost Planet Return to the Lost Planet Return to the Lost Planet is a 1954 juvenile science fiction novel by Angus MacVicar, published by Burke, London. It is the second of the Lost Planet series, which was adapted for radio and television. There are six novels in the Lost Planet series: "The Lost Planet" (1953), "Return to the Lost Planet" (1954), "Secret of the Lost Planet" (1955), "Red Fire on the Lost Planet" (1959), "Peril on the Lost Planet" (1960) and "Space Agent from the Lost Planet". It was the first science fiction series ever translated into Hebrew and had considerable impact