Jerome Cardan’s (Gerolamo Cardano, 24 September 1501 – 21 September 1576) method marked the first signs of what may be called a scientific approach to horoscopy. A number of historians have suggested that Cardan’s undoing was the horoscope of Christ, which he cast during the 1530s and published in 1557. The Church, supported by its Mafia-like Inquisition, could not conceive of Christ as participating in human nature (for all He was said to be both Man and God), and it was a tenet of belief that natal astrology dealt only with human nature. For some churchmen, the suggestion that Christ had been subject to planetary and cosmic influences seemed heretical.
Cardan’s imagined theological sin was one thing, but the horoscope was another: there was no possibility of its being accurate. Even by the sixteenth century, scholars recognized that the birth of Christ did not take place on the night of 24 December (or, as Cadan put it, in IX Calendis Ianuarii). Nor could it have taken place in year 1 (anni initium), as Cardan recognized in another version of the chart he cast for the birth of Christ.
The chart has some interesting elements: note for example, the curious symbol meant to denote the presence of a comet, which crosses the ascendant line in 02.43 Libra. This comet was included because Cardan believed that the Star of Bethlehem, which was reported as moving from east to west, guiding the Wise Men to the new-born Child, was nothing more than a comet.
The eight-pointed star above the comet is (typical of Cardan) a reference to a fixed star, which happens to be Spica, the star in the lap of Virgo, which has for centuries been associated with Jesus. It is true that, around that first Christian year, the star which Cardan called spica Virginis stella (the modern Spica) was very close to 02.43 Libra, which Cardan had specified as Christ’s ascendant. Earlier astrologers had made much capital out of this degree, for it fell in the first decan (a ten-degree division, or third part) of Libra, the traditional image for which was of a pure virgin, feeding a child. This, many astrologers maintained, was an image of the Virgin Mary.
Source: The History of the Horoscope by David Ovason
Twelve Days of Christmas Day 4