The Tropical zodiac has a precise starting point at the northern hemisphere spring and southern hemisphere fall equinox. But what about the sidereal zodiac? A zodiac requires a fiducial point on the circle from which measurements are made. Various measurements from specific stars were used in Mesopotamia to designate the initial points of zodiac signs. However, these stars were not exactly 30 degrees and zero minutes from each other, which leaves us with a zodiac with hazy sign boundaries.

Of the bright stars that lie close to the ecliptic, Spica is virtually the only candidate for a fiducial star that is located near a sign junction, and this junction happens to be just at the center of the sidereal zodiac between Virgo and Libra. Perhaps of greater interest is that Spica is only minutes in longitude from bright Arcturus to the north. Edgar Cayce gave great importance to Arcturus as evidenced from these quotes from his readings:

“For Arcturus is the way, the door out of this system.�?(2454-3)

“Not that the Sun as the center of the solar system is all there is. For the entity has attained to that realm even of Arcturus, or that center from which there may be the entrance into other realms of consciousness.�?(2823-1)