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Sidereal vs Tropical Astrology

Winterhawk / Wyn Summerhawk



I'm no astrologist by any stretch of the imagination. I know enough to realize that more matters than my Sun sign. I have to get a computer to do my charts for me because the math gets me tying my thumbs in knots. Still, something astrological has got my knickers in a twist. I've always trusted the Tropical system that makes me a Sagittarius. I seem to fit some of the descriptions of what one born under that Sun sign should be, and Libra ascendant explains some things about my behaviors.
Then I find out that the Tropical system is based on where the stars were a long time ago. Its not where they are now. The Sidereal system takes into account the movements of the constellations. The Sidereal system makes me a Scorpio. Every trait ends up being explained or described by the placements of planets in my chart under this system. My whole personality and the things I undergo show up accurately in the Sidereal calculations. What this tells me is the system works. I suppose I would have to have two astrologists of equally high caliber do a reading for me in the two systems and compare the results to be absolutely convinced that I am either a Sag or a Scorpio.
The bigger questions and concerns come to me when I consider the implications of using tropical calenders to determine Moon Void of Course. I've often gone by my feelings in choosing appropriate times to work magick, and found myself most comfortable and successful in times that showed up later to be Voids while magick done in a tropical Moon in Sign period proved duds. In fact much has gone awry when I was careful to do everything by the book under a Tropical Moon in Sign.
I started using a computerized astronomy chart to figure out where the Moon was. It turned out that the Tropical charts are off a great deal of the time from where the Moon really is in the sky. I'm going with Sidereal. Its accurate. Maybe I am a Scorpio. Its not all that important to me what my chart's doing but it matters a great deal what the sky is up to when I'm working magick. As I said, I am no Astrologist, so I give you Winterhawk who is one, to explain in technical terms what the differences are and why they are so important. Wyn Summerhawk
Needless to say the above story got me thinking as well. Recently a friend who is into Sidereal Astrology asked me to open in my Tropical Ephemeris, look up the position for the Moon, do the math to get the position for local time and look to see if the Moon was in that constellation outside. I did but, IT WASN'T!! I checked my math. My math was correct. I checked the ephemeris against my favorite program, Astrolog. It's coordinates were just fine and matched the program but, the planet wasn't there in reality. What happened?
Tropical Astrology is based on an imaginary point in space that the Earth comes to every spring. The Vernal Equinox, March 21st. That imaginary point is what keeps the seasons in their place and all Gregorian calendars are aligned to it every March 21st. (This is also why we have leap year.)
Before we go further, let me explain what Tropical and Sidereal are in scientific terms. (Not too scientific though)
Sidereal, or stellar, time is a system of time reckoning based on the rotation of the Earth with respect to the celestial sphere, the imaginary sphere of the heavens surrounding us. As the Earth rotates, one sidereal day is the time that it takes for a star to again pass directly above a given observation point. Sidereal time is used in astronomical work. The sidereal day is about four minutes shorter than the solar day. More precisely, 1 mean solar day = 1.0027379093 sidereal days. An observer's local meridian is the great circle passing through the observer's zenith and the celestial poles. The angle measured westward from this meridian to the hour circle is called the hour angle (HA) of the star. The hour angle of the vernal equinox is defined as the local sidereal time of the observer; therefore, right ascension + hour angle = sidereal time. Sometimes, in place of delta, the north polar distance (NPD) is used; this is the angle measured from the north pole to the star.


Since the vernal equinox and equator are not fixed, because of PRECESSION, it is necessary to specify at what date or epoch the coordinates were measured. For instance, on the vernal equinox (Spring or March 21) in the year 221, if you were to look up in the sky at noon on that date in Greenwich , England Aries would be right above your head at 0°. If you go out on March 21, 1996 at noon in Greenwich and look up you'll see 6° of Pisces. That's what precession does.
The Tropical year is the period of time of one revolution of the Earth around the Sun measured between successive vernal equinoxes. It equals 365.24220 mean solar days, or 365 days, 5 hours, 48 minutes, 46 seconds. Also called the solar year or the year of the seasons, the tropical year is the basis of the calendar. This is why winter happens in the northern hemisphere between December and March.
A year is a division of time defined basically by the period of revolution of the Earth around the Sun. Various kinds of astronomical years and calendar years have been defined. The astronomical year of chief importance to most of today's astrologers is the tropical year, which is the time interval between successive occurrences of the spring equinoxes. This is what keeps Aries at 0°. But, this is also an imaginary point.
A year is now about 365.2422 mean solar, or civil, days, the number decreasing very slowly as a result of small, progressive changes in the Earth's rotational speed and its orbit about the Sun. The seasons repeat, on the average, in this interval. The sidereal year, determined by the Earth's position with respect to the stars, is 365.25636 mean solar days which means that the year goes on a tiny bit longer every year. It is longer than the tropical year because it is not subject to the shortening effects of precession though it should be. This is what causes the vernal equinoxes to slowly go backwards in the signs.


If the vernal equinox occurs in Greenwich, England at 6° Pisces in 1996 then why are all the tropical astrologers trying to tell me that it's 0° Aries? If I go to my window and look up at the sky on that day in Greenwich I'll see the constellation Pisces!! When I was born using sidereal calculations for Chicago and my parents looked up at that second they would have seen the Sun in 10° Aries NOT 3° Taurus.


I'm not saying that spring should occur at 0x Aries.. That would put it somewhere in April... I think that the imaginary point that the Gregorian calendar is set to is great for the reference of changing seasons / Sabbots but, it is not a good idea for reference to astrology. The energy that is being produced by such and such a planet being in a sign does not follow any imaginary point. It just is! Summer in the Northern Hemisphere is Winter in the Southern.


Ptolemy, the father of todays astrology never heard of tropical astrology. He went out on his balcony and looked up. If Jupiter was in Cancer it was in Cancer. This change from Sidereal to Tropical Astrological systems can't quite be pinned down. Some texts say that it occurred in the 1600's others say that Tropical gained acceptance somewhere in 1800's when Greenwich, England was chosen as the place of 0 hour. I might also suggest that the split between Astrology and Astronomy was due to that imaginary point. While astrologers made their mathematical computations to always put Aries at 0° on March 21st, astronomers were looking through their telescopes and shaking their heads saying, "I beg to differ.. Here.. Take a look for yourself". By today's standards the zodiac is now off by 24°
Cyril Fagan came upon the same conclusion in 1944. He spent the last 26 years of his life trying to convince astrologers of the tropical zodiac that the fixed sidereal zodiac was the one to be looked at when casting anyone's charts. In his book, A Primer of Sidereal Astrology he explained in even more complicated terms, but never the less, convincingly the how's and whys of what is being discussed herein. Not to many people listened. I personally think he tried to simplify too much. Later Eshelman and Stanton carried on his work and began to attract followers to sidereal astrology with their book, The New Instant Astrologer.


Ask yourself this question, "How come when someone does my chart they just don't quite get it"? With an astrological system off by 24° there would by a load of room for error. Sun would be off by 24°, rising sign would be off.. therefore the houses will be off.. etc, etc. This also means that the planets used in Tropical Astrology are off by 24°. (Ever wonder why astronomers are laughing at astrologers?).
Alas, this also means that the predictions given by Tropical astrologers are off by years. I can hear it now...Wait, wait, wait.. Hawk.. where's your proof? Just by chance I picked up a book called Astrological Megatrends by Kluska. What he predicts (Tropically....then) is happening Sidereally now. This is to say he was early in his predictions.


Example: Tropically Uranus is in Aquarius, Sidereally it just entered Capricorn. Kluska's predictions for Uranus in Capricorn are NOW coming true not ten years ago. He predicted that everyone would have computers in 1988, when in reality only 15% of the population had them. Look around you now. Nearly 65% to 70% of the population has them.. and their all connected to the inter net.(Uranus).
Example: Tropically Neptune is supposed to go into Aquarius in January of 1998. Sidereally, it's 4xCapricorn. What Kluska predicted for the Congress never happened until the 90's. This is when Neptune's rays started to effect us. (Planets rays = +/- 3° of a sign on average).
Example: Tropically Pluto just entered Sagittarius. Sidereally it just entered Scorpio. This doesn't bode well. What was supposed to happen when Pluto entered Scorpio that didn't when the tropicalists said it would is now happening. Look at the news. Things like investigations of the FBI, Congress looking at the Clinton's... Privacy issues on the inter net, all the extreme things going on NOW are products of Pluto in Scorpio.


As of late, some astrologers put the date of the age of Aquarius at 1987 with the great alignment. I disagree. If we're using the PRECESSION as the date it won't be here until 2356. Mark it on your calendars. That's when the Spring Equinox will take place at 29° Aquarius 59'.
If we as a magickal community are going to use the powers that are available to us through history we should make every effort to ensure that they are correct. Sidereal Moon void of courses, the sign a planet is in and the timing of the aspects are NOT the same as tropical, although the actual aspects themselves are, i.e., when Neptune is square Moon tropically or sidereally...it is. The definitions of the signs, planets, or aspects are still the same. The only difference is the actual timing.


Now when I do a sidereal chart to see if the Moon is void (don't want to do spells when it is) and the chart tells me that the Moon is in Cancer; I can go outside, look up, and sure enough that's where She is!!




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