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Transpluto(religion, spiritualism, and occult)
Of the many hypothetical planets postulated by astrologers, the one most likely to have an empirical existence is Transpluto, so called because, if discovered, it would be found beyond the orbit of Pluto. This hypothetical planet has been called by many different names—Persephone, Isis, Minerva, and Bacchus, to name a few—but Transpluto is its most commonly accepted designation. Many astrologers have been attracted by the idea of one or more transplutonian planets, because their discovery would allow astrologers to complete the transferral of sign rulerships that has been in progress since the discovery of Uranus: In the premodern system of sign rulerships, each of the traditional planets ruled two signs apiece, while the luminaries (the Sun and the Moon) each ruled one sign. As the outer planets were discovered, the rulerships of Aquarius, Pisces, and Scorpio were gradually transferred to Uranus, Neptune, and Pluto, leaving Saturn, Jupiter, and Mars as the rulers of Capricorn, Sagittarius, and Aries. Only Mercury and Venus are still viewed as ruling two signs each.
Because of the attractiveness of a balanced system in which 12 heavenly bodies rule 12 signs, twentieth-century astrologers have often speculated that two new planets would eventually be discovered and come to be accepted as the rulers of Virgo and Libra. In particular, it has been speculated that the hypothetical planet Vulcan, which some astronomers said could be found between the Sun and Mercury, is the ruler of Virgo, while Transpluto has been thought to rule Libra. The abandonment of the notion of an intramercurial planet by astronomers has also tended to call into doubt the notion of an extra-Plutonian planet, and some contemporary astrologers have begun to put forward certain asteroids as candidates for the rulerships of Virgo and Libra.
Neptune was discovered by astronomers who used perturbations in the orbit of Uranus to calculate the position of a transuranian planet. Its position was determined mathematically by a Frenchman as well as an Englishman, and German astronomers were actually able to locate the new planet. In a similar manner, some astrologers believe they have enough data to plot the orbit of a transplutonian planet, and more than one ephemeris has been published (Transpluto has even been incorporated into chart-casting programs). The most significant astrological publication in this area is John Robert Hawkins’s book Transpluto, Or Should We Call Him Bacchus, the Ruler of Taurus? which includes an ephemeris as well as preliminary delineations for Transpluto’s house positions, sign positions, and aspects. Transpluto, Or Should We Call Him Bacchus has generated enough interest to merit three printings, but the transplutonian planet is still outside the astrological mainstream and will undoubtedly remain so until astronomers definitively establish its existence.