Posted on 01/11/2022 11:43:06 AM PST by Red Badger
I was born a Capricorn (please don’t judge me), but the Sun was in the middle of Sagittarius when I was born.
As a professor emeritus of astronomy, I am often asked about the difference between astrology and astronomy. The practice of astrology, which predicts one’s fate and fortune based on the positions of the Sun, Moon, stars and planets, dates back to ancient times. It was intermingled with the science of astronomy back then – in fact, many astronomers of old made scientific observations that are valuable even today. But once Copernicus, Kepler and Galileo realized the planets orbit the Sun, rather than the Earth, and Newton discovered the physical laws behind their behavior, astrology and astronomy split, never to be reunited.
The science of astronomy is now at odds with one of the basic organizing principles in astrology – the dates of the zodiac.
The constellations of the zodiac
Over the course of a year, the Sun appears to pass through a belt of sky containing 12 ancient constellations, or groupings, of stars. They are collectively called the zodiac and consist almost entirely of animal figures, like the ram (Aries), crab (Cancer) and lion (Leo). It is a disappointment to many that the constellations only rarely look like what they represent. How could they, since they are truly random scatterings of stars? They are meant to represent, not to portray.
The word ‘zodiac’ comes from a Greek phrase that means ‘circle of animals’. Tartila/Shutterstock.com
Although the constellations of the zodiac, which date back to Mesopotamia or before, may seem definitive, they are only one example of those produced by the various cultures of the world, all of which had their own, frequently very different, notions of how the sky is constructed. The Incas, for example, made constellations not from stars, but from the dark patches in the Milky Way.
The number of constellations in the Western zodiac comes from the cycles of the Moon, which orbits the Earth 12.4 times a year. Roughly speaking, the Sun appears against a different constellation every new Moon, the stars forming a distant backdrop to the Sun. Though the stars are not visible during daytime, you can know what constellation the Sun is in by looking at the nighttime sky. There you will see the opposite constellation.
The Sun is in Leo here, which means at night, you’d see Aquarius. PNGGuru, CC BY-NC
Astrology suggests that each sign of the zodiac fits neatly into a 30-degree slice of sky – which multiplied by 12 adds up to 360 degrees. In actuality, this is not the case, as the constellations vary a great deal in shape and size. For example, the Sun passes through the constellation Scorpio in just five days, but takes 38 days to pass through Taurus. This is one of the reasons astrological signs do not line up with the constellations of the zodiac.
Precession of the equinoxes
The main reason astrological signs fail to line up with the zodiac, though, is a wobble in the Earth’s rotational axis called precession. As a result of its rotation, the Earth bulges slightly at the equator, not unlike how a skater’s skirt fans out as she spins. The gravity of the Moon and Sun pull on the bulge, which causes the Earth to wobble like a top. The wobble causes the Earth’s axis, which is the center line around which it rotates, to swing in a slow circle over the course of 25,800 years.
A wobbling Earth causes the dates of the zodiac to shift from those established in ancient times. This movement alters the view of the zodiac from Earth, making the constellations appear to slide to the east, roughly a degree per human lifetime. Though slow, precession was discovered with the naked eye by Hipparchus of Nicaea around 150 B.C.
In ancient times, the vernal equinox – or the first day of spring – was in Aries. Due to precession, it moved into Pisces around 100 B.C., where it is now and will remain until A.D. 2700, when it will move into Aquarius and so on. Over the course of 25,800 years, it will eventually return to Aries and the cycle will begin again.
What constellation was the Sun in on your birthday? These dates are correct for people alive today, but as the Earth wobbles, the dates will continue to change, as they always have.
Constellation Dates
Aries - April 19 – May 14
Taurus - May 15 – June 20
Gemini - June 21 – July 20
Cancer - July 21 – August 10
Leo - August 11 – September 16
Virgo - September 17 – October 31
Libra - November 1 – November 24
Scorpio* - November 25 – December 17
Sagittarius - December 18 – January 19
Capricorn - January 20 – February 16
Aquarius - February 17 – March 11
Pisces - March 12 – April 18
*Scorpio is combined here with the constellation, Ophiuchus, through which the Sun passes between November 30 and December 17. (It is not part of the Zodiac, however.)
Table: The Conversation, CC-BY-ND Source: The Ever-Changing Sky A Guide to the Celestial Sphere by James B. Kaler Get the data
As a game, astrology and its predictions of fate and personality can be fun. However the subject has no basis in science. It is to science what the game “Monopoly” is to the real estate market.
Astrology diverts attention away from the very real influences of the planets, primarily their gravitational effects on one another that cause real changes in the shapes, sizes and tilts of their orbits. On Earth, such changes likely caused past ice ages. Direct collisions between Earth and celestial bodies can cause very rapid changes, such as the impact of an asteroid off the Yucatan Peninsula 66 million years ago that had global effects including the disappearance of dinosaurs and the rise of mammals.
Astronomical studies will eventually allow the prediction of such events, while astrological predictions will get you absolutely nowhere.
You will have to weigh that situation carefully even though it may sting.............
Or had been knowledgeable in their predictions which in any case never work out.
Hahahaha.
Very good.
Astrology is basically nonsense. The ancients did not understand that (a) the “movement” of the sun through the constellations of the zodiac is really the movement of the earth around the sun, so the zodiac constellation that the sun is in is really the one furthest (!) from the earth; and (b) stars are immensely far away ... for example, the two brightest stars in Aquarius are both about 500 light-years from earth. The only “influence” those stars have is the light (and other radiation) they shed, and their gravity. Both are tiny at this distance. I can do the math if anyone cares, but I’m certain that the steel teaspoon you hold in your hand has more gravitational pull on you than either one of those two stars.
‘Dagon’ was a mediocre movie.
I recommend “The Last Lovecraft: Relic of Cthulu”, a funny movie.
https://www.imdb.com/title/tt1522262/plotsummary?ref_=tt_ov_pl
Jeff is an ordinary guy that is stuck at a dead end job with a boring life, but when a strange old man gives him an Ancient relic and tells him that he is the last bloodline of H.P. Lovecraft, He and his friend Charlie embark on an adventure to protect the relic piece from falling into the hands of the Starspawn and his minions that wish to reunite the relic and release Cthulhu back into the world.
This is the best and clearest explanation of astrology vs. astronomy that I have ever read. For all his expertise though, the author advances the biggest mistake nearly everyone makes in trying to understand astrology: astrology doesn’t predict, it indicates. The nonsense of “astrological predictions” that are published in daily papers and/or magazines is just that - nonsense.
While Aristarchus championed a heliocentric model, his “discovery” was little more than speculation. The superiority of Ptolemy’s model was that it could be used to make useful predictions. It wasn’t until Tycho made long-term accurate measurements of planetary motion that a better theory was necessary. Copernicus’s theory really isn’t any better, in that its predictions were no more accurate than Ptolemy’s. In fact, given that Copernicus needed more terms, literally more epicycles, it involved more computations and more parameters. Occam’s razor favors Ptolemy over Copernicus.
Kepler’s theory, or simply Kepler’s laws were the first real advance over Ptolemy in 1400 years. Coupled with Newton’s Law of Motion (published by Hook 12 years earlier, and usurped by Newton without attribution) they revolutionized astronomy, and ultimately, science.
A question for Freepers:
What sign were you conceived under?
Actually, Mrs. POF probably would say I'm a crabby Cancer.
No Vacancy........................
Ha Ha Ha.
I am a Libra, once had a Taurus, and traded it in for a Colt. (Sagittarius?)
Emergency Entrace
Cassius:
“The fault, dear Brutus, is not in our stars,
But in ourselves, that we are underlings.”
My favorite horoscope was on a paper placemat in a diner back in the 70’s.
Aquarius (1/20 - 2/18) You have an inventive mind and are inclined to be progressive. You lie a great deal. On the other hand, you are inclined to be careless and impractical, causing you to make the same mistakes over and over again. People think you are stupid.
Pisces (2/19 - 3/20) You have a vivid imagination and often think you are being followed by the CIA or FBI. You have minor influence over your associates, and people resent you for flaunting your power. You lack confidence and are generally a coward. Pisces people do terrible things to small animals.
Aries (3/21 - 4/19) You are the pioneer type and hold most people in contempt. You are quick tempered, impatient, and scornful of advice. You are not very nice.
Taurus (4/20 - 5/20) You are practical and persistent. You have a dogged determination and work like hell. Most people think you are stubborn and bullheaded. You are a Communist.
Gemini (5/21 - 6/20) You are a quick and intelligent thinker. Most people like you, as you are bisexual. However, you are inclined to expect too much for too little. In other words, you are cheap. Geminis are known for committing incest.
Cancer (6/21 - 7/22) You are sympathetic and understanding to other people’s problems. They think you are a sucker. You are always putting things off; that’s why you’ll never make anything of yourself. Most welfare recipients are Cancer people.
Leo (7/23 - 8/22) You consider yourself a born leader. Others think you are just pushy. Most Leos are bullies. You are vain and dislike honest criticism. Your arrogance is disgusting. Leo people are thieves.
Virgo (8/23 - 9/22) You are the logical type and hate disorder. This nit-picking is sickening to your friends. You are cold and unemotional and sometimes fall asleep while making love. Virgos make good bus drivers.
Libra (9/23 - 10/22) You are the artistic type and have a difficult time with reality. If you are a man, you are more than likely gay. Chances for employment and monetary gain are excellent. Most Libra women are good prostitutes. All Libras die of venereal disease.
Scorpio (10/23 - 11/21) You are shrewd in business and cannot be trusted. You will achieve the pinnacle of success because of your total lack of ethics. Most Scorpios are murdered.
Sagittarius (11/22 - 12/21) You are optimistic and enthusiastic. You have a reckless tendency to rely on luck, since you lack talent. The majority of Sagittarians are drunks or dopers. People laugh at you a great deal.
Capricorn (12/22 - 1/19) You are conservative and afraid of taking risks. You don’t do much of anything; you are lazy. There has never been a Capricorn of any importance. Capricorns should avoid standing still for too long, as they take root and become trees.
7000 year-old Sumerian agronomy used to determine planting and harvesting schedules has devolved in today’s astrology. It’s awfully silly, really.
I wanna be an Ophiuchian!
How 'bout Jesus, Elvis and Richard Nixon, ... and me?
No Parking
-PJ
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