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If you're confused about the differences between astrology and astronomy, let me set the record straight right here.   Astronomy is a science that seeks to understand the workings of the cosmos, and corrects itself as we discover newer and better evidence.  Astrology is an ancient belief system that hasn't changed for thousands of years and, despite what many people claim, has no basis in reality. 

To begin to understand the profound weaknesses of astrology, take a look at one of its most fundamental concepts: the sun sign.

The sun's annual path (caused by the Earth's orbital motion) takes it across a thin band of sky known as the zodiac and, along the way, the sun passes in front of a number of star groupings known as constellations.   If we could see the sun and stars at the same time, our "sign" would be the constellation against which the sun lay at the time we were born.  Thus we have such "signs" as Aries, Taurus and Sagittarius, each of which corresponds to a star grouping in the heavens.

What most people don't realize is that, since astrology's origin millennia ago, it has failed to keep up with our increasing knowledge of the cosmos.  For example, scientists know today the Earth undergoes a 25,800-year wobble which, over time, alters the positions of celestial bodies. 

So what, you ask?  This means that the "sign" to which you think you "belong" is probably not the constellation in which the sun lay at the time of your birth―unless, of course, you were born thousands of years ago.  

For example, suppose your birthday is on June 12.  You've lived your entire life believing your "sign" to be Gemini.   What a shock it must be to learn that, when you were born, the sun really appeared against the stars of Taurus (see table below)!  

And what about those born on the morning of March 27, when the sun appears over the boundary between two constellations:  Pisces, the fishes and the whale.  Or those poor souls born between November 29 and December 17?  They've been relegated to the "sign" of Ophiuchus―the Serpent Bearer!   

So much for the usefulness of astrology!

To learn more about the subject, visit Horoscopes Versus Telescopes:  A Focus on Astrology.

To discover where the sun actually appeared when you were born, check out the following table.

If your birthday falls between these dates...

The sun appears
here on your birthday...

Days  spent

Astrological date range for this constellation*

Mar 12 - Apr 18 Pisces** 38 Feb 19 - Mar 20
Apr 19 - May 13 Aries 25

Mar 21 - Apr 19

May 14 - Jun 21 Taurus 39 Apr 20 - May 20
Jun 21 - Jul 20 Gemini 29 May 21 - Jun 21
Jul 21 - Aug 10 Cancer 21 Jun 22 - Jul 22
Aug 11 - Sep 16 Leo 37 Jul 23 - Aug 22
Sep 17 - Oct 30 Virgo 44 Aug 23 - Sep 22
Oct 31 - Nov 22 Libra 23 Sep 23 - Oct 23
Nov 23 - Nov 28 Scorpius 6 Oct 24 - Nov 21
Nov 29 - Dec 17 Ophiuchus*** 19


Dec 18 - Jan 19 Sagittarius 33 Nov 22 - Dec 21
Jan 20 - Feb 16 Capricornus 28 Dec 22 - Jan 19
Feb 17 - Mar 11 Aquarius 23

Jan 20 - Feb 18

* These are nearly equal in length, and bear little resemblance to the real world!

** For a few hours on the morning of Mar 27, the sun straddles both Pisces and Cetus.

*** Yes, Ophiuchus!  Notice the sun spends longer here than it does in Scorpius!

Dennis Mammana






(c) Dennis L. Mammana.  All rights reserved.