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Conjunction of the Sun and Regulus on August 23

Sun-Regulus' Conjunctions & the Zodiac


Yearly, on or near August 23, the Sun passes between the Earth and Regulus, the brightest star in the constellation Leo the Lion. This annual conjunction of the Sun and Regulus comes about 2 months after the June 21 solstice and 1 month before the September 23 equinox.
If you're familiar with astrology (or more specifically: tropical astrology), you may know the Sun occupies the first or zero point of the sign Cancer on the June solstice and the first point of the sign Libra on the September equinox. No matter the year, the Sun is always at the First Point of (the sign) Aries on the March equinox, the first point of (the sign) Cancer on the June solstice, the first point of (the sign) Libra on the September equinox and the first point of (the sign) Capricorn on the December solstice.
The reader may wonder: what does this have to do with Regulus, the brightest star in the constellation Leo the Lion? Once and for all, I'm hoping I can use this star to highlight the difference between an astrological sign and an astronomical constellation. Oftentimes, both astrologers and astronomers confuse one for the other. Either term is perfectly correct to use, as long as you don't mistakenly call a zodiacal constellation a zodiacal sign, or vice versa.

Astrological Signs

Signs refer to the Sun's place on the zodiac relative to the March equinox (First Point of Aries), IRRESPECTIVE of the Sun's position relative to the background stars - or in this case, the star Regulus. At the March equinox, the Sun is at the first or zero point of (the sign) Aries. One month later, when the Sun is 30 degrees east the March equinox point, the Sun stands at the first point of (the sign) Taurus. Two months later, when the Sun resides 60 degrees east of the March equinox point, the Sun marks the first point of (the sign) Gemini. Some three months after the March equinox, the Sun is 90 degrees east of the March equinox point, at the first point of (the sign) Cancer - this also marking the Sun's June solstice point.
And so on and so forth . . .

Regulus' Astrological Position

Five months after the March equinox, on or near August 23, the Sun shines at 150 degrees (5 months x 30 degrees = 150 degrees) east of the March equinox point. That's the same date the Sun and Regulus are in conjunction! According to Anne Wright on her Regulus page, Regulus won't be at the first or zero point of the sign Virgo till 2012. Presently, Regulus resides almost exactly at the border of the signs Leo and Virgo, though technically speaking, this star is still within the sign Leo. Even though Regulus belongs to the constellation Leo, Regulus passes through all the signs of the zodiac in about 26,000 years.
As a rule of thumb, Regulus goes one degree eastward through the signs of zodiac in 72 years. That's 30 degrees eastward in 2160 years. (What a coincidence, the moon's diameter equals 2,160 miles!) If, then, Regulus stands at the first point of the sign Virgo in the year 2012, we can calculate the year that the Sun and Regulus were in conjunction on the June solstice, and the year they'll be in conjunction on the September equinox.

Regulus at June Solstice Point & September Equinox Point

Nowadays, Regulus stands very close the first point of the sign Virgo: 150 degrees east of March equinox point, and 60 degrees east of the June solstice point. Going backward in time, we can figure that Regulus stood at the June solstice point some 4,320 years ago (60 degrees x 72 years = 4,320 years). Therefore, according to our calculations, Regulus was at the first point of the sign Cancer (June solstice) in 2308 BC (2012 - 4320 = 2308). According to Anne Wright, Regulus marked the first point of the sign Cancer in 2345 BC. At least our figure is within the ballpark.
Looking into the future, Regulus will be at the first point of the sign Libra, or 180 degrees east of the March equinox point, in about 2160 years from the year 2012. Accordingly, the Sun and Regulus will be in conjunction with one other on the September equinox somewhere around the year 4172.

copyright 2007 by Bruce McClure

Dates of the Sun's passage through the Zodiacal Signs & Constellations!

July 2007 feature * Sept 2007 feature