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Vulcan,in astronomy, hypothetical planet whose existence was proposed by Le VerrierLeverrier, Urbain Jean Joseph
, 1811–77, French astronomer who made calculations that led to the discovery of the planet Neptune. In considering the perturbations of Uranus, Leverrier made calculations indicating the presence of an unknown planet in an orbit outside that
..... Click the link for more information. to explain part of the advance of the perihelion of MercuryMercury,
in astronomy, nearest planet to the sun, at a mean distance of 36 million mi (58 million km); its period of revolution is 88 days. Mercury passes through phases similar to those of the moon as it completes each revolution about the sun, although the visible disk varies
..... Click the link for more information. , not all of which could be accounted for by gravitational effects of the other planets under the Newtonian theory of gravitationgravitation,
the attractive force existing between any two particles of matter. The Law of Universal Gravitation
Since the gravitational force is experienced by all matter in the universe, from the largest galaxies down to the smallest particles, it is often called
..... Click the link for more information. . The general theory of relativityrelativity,
physical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference.
..... Click the link for more information. , which explain the observed advance of the perihelion of Mercury as being caused by the curvature of space in the vicinity of the sun as a result of the sun's large mass, ended the search for Vulcan.
Vulcan,in Roman religion and mythology, fire god. Chiefly a god of destructive fire, Vulcan seems to have originated as a god of volcanoes. His festival, the Volcanalia, was held on Aug. 23. He was later identified with the Greek HephaestusHephaestus
, in Greek religion and mythology, Olympian god. According to Homer he was the son of Hera and Zeus, but Hesiod states that he was conceived and borne by Hera alone. Originally an Asian fire god, in Greece he became the divine smith and god of craftsmen.
..... Click the link for more information. .
Vulcan(vul -kăn) A hypothetical planet, thought during the 19th century to orbit the Sun within the orbit of Mercury. Searches for it during total solar eclipses and at suggested times of transit across the Sun were all unsuccessful. It is now known not to exist.
Vulcan(religion, spiritualism, and occult)
Vulcan (related to the word volcano) is a “hypothetical planet” (sometimes referred to as the trans-Neptunian points or planets, or TNPs for short) that astronomers formerly speculated would be—and that a few astrologers still anticipate will be—found orbiting the Sun inside the orbit of Mercury. The nineteenth-century French astronomer Urbain Le Verrier was the first person to hypothesize its existence and, shortly after he made his theories known, people began to claim that they had observed Vulcan. It was named after the ancient Roman god of fire, who was also blacksmith to the gods. Alice Bailey’s system of esoteric astrology makes extensive use of Vulcan, and some esoteric astrologers still utilize it. Many astrologers anticipated that Vulcan, when discovered, would be assigned the rulership of Virgo. As astronomers gradually abandoned the notion of an intermercurial planet, Vulcan slowly faded from astrological discourse. There is, for example, no entry for Vulcan in such standard references as the Larousse Encyclopedia of Astrology or Eleanor Bach’s Astrology from A to Z. Thanks to the Star Trek television series, the name is still alive, although Mr. Spock’s home planet bears little resemblance to the hypothetical planet of astronomical history.
["VULCAN - A String Handling Language with Dynamic Storage Control", E.P. Storm et al, Proc FJCC 37, AFIPS, Fall 1970].
["Vulcan: Logical Concurrent Objects", K. Kahn et al in Research Directions in Object- Oriented Programming, A.B. Shriver et al eds, MIT Press 1987].