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Traditional Rulerships
of the Planets

saturn Saturn
jupiter Jupiter
mars Mars
the sun The Sun
venus Venus
mercury Mercury
the moon The Moon
The Birth of the Outer Planets by David McCann


Discovery - Chart - Naming

See also: Uranus | Neptune

The discovery of Pluto

Just as irregularities in the orbit of Uranus had led to the search for Neptune, so in turn the motion of Neptune led to the suspicion that there might be another new planet to discover. The search was started by Percival Lowell in 1877 and continued on and off until Clyde Tombaugh found the planet in 1930. The reason for the long delay was that they had been looking for a much brighter object - a planet several times larger than the Earth. In fact, Pluto's mass is quite insufficient to produce the results from which his existence was inferred! This is all the more odd, considering that Lowell had estimated the orbit's size, eccentricity, and inclination so well that the planet was found within six degrees of the position predicted from his figures.

The timing of the discovery of Pluto is less clearcut than that of Neptune. It was found on 18 February 1930, but by the comparison of photographs taken on 23 and 29 January. In a pleasant gesture, the announcement was delayed until Lowell's birthday. Although Lowell was dead, his nativity (7.30 a.m. LT, 13 March 1855, Boston Mass.) responded to the discovery, transiting Pluto opposing his tenth house Moon. It is interesting that the two planets with which Lowell was chiefly concerned, Pluto and Mars, were both unaspected in his nativity: was he trying to fill a personal void?

Pluto Discovered

It is perhaps typical that Pluto should conceal himself in the twelfth house, though he is in conjunction with the East Quarter. The fourth harmonic chart, indicating how he will manifest in worldly affairs, shows a striking T-square: Pluto in opposition to a Venus-Neptune conjunction, squared by Mars. It is difficult to interpret ones own century, but that T-square looks to me like sex, drugs, and rock and roll!

As with the other new planets, the discovery chart presaged and responded to appropriate events. Thus one of the rulerships of Pluto is atomic energy. In 1932, Cockcroft and Walton split the atom. At the end of 1942 nuclear fusion was achieved, with transiting Pluto opposing radical Mars in the discovery chart. When the atomic bomb was dropped on Hiroshima in 1945, transiting Saturn opposed radical Pluto.

Where the discovery of the astrological significance of Uranus and Neptune had taken many years, the first account of Pluto was published by Fritz Brunhübner as early as 1932.

The Naming of Pluto

The name Pluto was submitted to a newspaper competition by Venetia Burney, an Oxford schoolgirl, though it seems that she had the cartoon dog in mind rather than the god of the underworld.[1]

The Greek Plouton is derived from ploutos 'wealth', which according to an ancient scholar originally referred to grain. This fits Pluto's association with the Earth and his role as the husband of the fertility goddess Persephone, though it says nothing of the astrological Pluto. But Pluto's role as a god of death is clearly appropriate to its astrological influence.

Source for chart data: Nick Campion's Book of World Horoscopes

  1 ] In response to this comment Andrew J. Bevan writes:

"David McCann's reference to Venetia Burney is incorrect an incomplete. Venetia was 11 years old, well versed in Greek and Latin mythologys and suggested the name Pluto for a dark and gloomy planet. Her grandfather, F.Madan, sent the suggestion to HH Turner, professor of astronomy at Oxford. F.Madan was a younger brother of Henry Madan who had suggested the names of Deimos and Phobos for the two Mars' dwarf satellites. I have this version from material circulated by Al H. Morrison."
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David McCann is an expert on the history and philosophy of astrology. His articles have been published in many international journals of astrology and he was a regular contributor to the Traditional Astrologer magazine, where this article first appeared.

© David McCann

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