- Education and Science
Astrology and Astronomy: Similarities and Differences
Similarities and Differences Between Astrology and Astronomy
Cold hearted orb that rules the night, removes the colours from our sight.
Red is gray and yellow white. But we decide which is right, and which is an illusion.
- Moody Blues, "Nights in White Satin" Days of Future Passed
I can still remember when in casual conversation, I had mentioned to someone that I had studied Astronomy in college. The conversation continued until, at last it was time to depart. However, before leaving, he mentioned that he had never met anybody that majored in "Astrogeny" before.
With good reason, I guess. When I was in school, there were about a dozen people to graduate in Astronomy in the U.S. per year. To put that in perspective, there are probably more people working for MacDonalds' in your city than working as Astronomers in your state. (I don't have any figures for professional Astrologers, but it seems to currently flourish in the West, China, and India.)
It would seem that a certain percentage of the the public has no real idea what an Astronomer is, let alone an Astrologer.
Just what is the difference between Astrology and Astronomy?
Jyoti Kothari asked me to write a hub on the subject of Symmetries and Dissimilarities between Astrology and Astronomy.
I will try to provide a brief outline here.
It would seem that most people should be aware of the difference. You can read your Horoscope in the daily newspaper, find a program to do his on your computer or the internet, and even log onto Facebook to do this. Most folks are aware that there are 12 signs of the zodiac, one for each month (or phase of the moon). That's Astrology for the popular culture. There is usually some comment about your behavior or your fortune for the day.
But, don't look in your daily newspaper, or log into Facebook to find daily wisdom from an Astronomer. There's a good chance that you won't see a momento about your daily behavior from any popular Astronomer. (Astronomers don't sell horoscopes or make predictions about the behavior of individuals.)
On the other hand, you probably won't find an Astrologer working at NASA. Astrologers typically can't tell you how much fuel it takes to get to the moon, or Mars. Astrologers simply don't advise on how to chart the course to celestial bodies.
How did Astrology get so popular that it began to be run in daily newspapers?
What are the differences between Astrology and Astronomy?
How did the two get started? Would it help to understand the differences if we understand how the two were developed?
Astrology is more ancient, and Astronomy is considered to be the more recently developed. The split between Astrology and Astronomy has not always been clear, and the separation was often messy.
How are each of the two defined?
Examples of Typical Applications
The ancients used Astrology in order to know when to plant or harvest crops, or handle livestock. In this sense, they needed to know how to predict the seasons, or how to predict the cycles of the moon. The position of the stars and the moon could help tell them at what time of the year they could safely plant crops. This would mean they could avoid crop failures or avoid starvation in winter.
Modern day astrologers would have you believe that the position of the planets or the moon has an influence on day to day life. Charting horoscopes could be expected in order to influence human behavior.
Modern day Astronomers are not concerned with human behavior. People apply Astronomy to know how much energy it takes to get to the moon or perhaps, the planets (i.e., force needed to escape the gravity of the earth, escape velocity, etc.). Astronomers also have the ability to chart the course of minor bodies, such as asteroids. Celestial mechanics is used to chart the course of spacecraft voyages. Most Astronomers would probably tell you that with the modern day calendar, the question of when to plant crops is probably best left to the local weatherman or farmer himself.
Astrology appears to have been developed in different cultures over different time frames. The most notable examples of the study of Astrology in ancient times have been found in the Middle East, Egypt, Europe, China, and the Americas.
Astrology is the more ancient study of celestial positions, with the charting of the planets and stars enjoying a long history. In contrast, Astronomy is a more recent development. Astronomy (by most accounts) marks it's beginnings at about the time of the Renaissance, and has diverged from Astrology ever since. In order to understand the differences between Astronomy and Astrology, it is helpful to understand how the science began to separate from the art (several hundred years ago).
The study of the positions of the stars, planets, and the moon began thousands of years ago. Notable examples include the development of pyramids in Egypt and the Americas (i.e., the Mayan culture). It is also thought that the Stonehenge in England served as a calendar in order to mark the positions of the Sun and the moon. Other cultures that have independently studied celestial positions include the Persians, Arabian, Greek, Roman, and Chinese cultures.
It is thought that the celestial studies of the ancients were originally used as an aide for planting or harvesting crops, or as in the case of Egypt, to aide in religious ceremonies for eternal life. If this is true, then it could be said that astrology was used originally used to provide advice for human behavior.
It appears that Claudius Ptolemy of Alexandria was the first to record a mathematical method for predicting the positions of the planets. At around 140 A.D. he compiled a 13 volume work on astronomy known as the Almagest. He proposed that the Earth was the center of the Universe. His philosophy was wrong, but the mathematics worked. Later, the Christian Church would embrace his philosophy that the Earth was the center of the Universe. Many years later, the Church would persecute and even burn (alive) at the stake any who would oppose "the scriptures."
Geometry was the main mathematical tool for astronomers of the period.
Ptolemaic model of the universe
Aside from the scriptures, astrological arguments for the Earth being the center of the Universe were based upon such concepts as "Heaviness" and "Lightness." That is, everything that was heavy would fall to the earth. Therefore, the earth had to be the center. Other arguments by astrologers were that if the earth rotated on it's axis, the speed would cause everything to "fly apart," instead of sticking together. (Copernicus, "On the Revolutions of the Heavenly Spheres" Chapter 7.)
Astrology generally follows the theme that either celestial bodies are signs or portents of events, or they are actual causes of events through some sort of unknown mechanism.
Astronomy generally follows the theme that celestial bodies have no influence upon human behavior, but can be scientifically measured using the natural laws of physics.
Nicholas Copernicus (1473-1543)
It wasn't until Nicholas Copernicus proposed that the earth was NOT the center of the Universe that the central concepts of modern Astronomy began to take form. For such a revolutionary concept, he waited to the end of his life to actually publish the mathematical proof of his theorems ("De revolutionibus orbium coelestium" - or, "On the Revolutions of the Heavenly Spheres").
Indeed, during this period in history, several Astronomers were persecuted (or killed) by the Church, including Tycho Brahe, Bruno, Kepler, and Galileo. Astronomers have had to pay dearly for the development of the "new" science.
Giordano Bruno (1548 – February 17, 1600)
Best known as a proponent of the infinity of the universe. His cosmological theories went beyond the Copernican model in identifying the sun as just one of an infinite number of independently moving heavenly bodies: he is the first man to have conceptualized the universe as a continuum where the stars we see at night are identical in nature to the Sun.
Bruno was burned at the stake by authorities in 1600 after the Roman Inquisition found him guilty of heresy.
Tycho Brahe (1546-1601)
Danish Astronomer. Tycho Brahe was fairly prolific with the construction of measuring instruments, and had built an observatory. Known for his extensive collection of fairly accurate measurements (for the time period). Tracked the supernova explosion of 1572 in the constellation of Cassiopeia, and tracked the path of the comet of 1577.
Tycho Brahe was doubtful about astrological predictions. "Astrologers do not bind man’s will to the stars, but confess that there is something within man that is raised above the level of the stars..." he said, on one occasion in a lecture at the University of Copenhagen in 1574.
But King Fredrik expected Tycho Brahe to make annual predictions. Tycho was also commissioned to cast birthday horoscopes for the Danish princes. Some would argue that his 1583 horoscope for Duke Hans (son of Fredrik II) correctly predicted the Duke's death in 1602. The horoscopes are now kept at The Royal Library in Copenhagen.
Tycho did not adopt the Copernican view, but continued to hold the view that the earth was the center of the universe. He measured the positions of planets so accurately that Kepler later could use these to deduce his famous three laws of planetary motion.
Galilei Galileo (1564-1642)
It was about the time of Galileo that many believe the science of Astronomy began to depart from Astrology. Galileo is known for his studies that included instruments for making measurements. He is credited with the first to record the planets by the use of a telescope, as well as measuring the time it takes balls to roll down an incline. His experiments on the motion of falling bodies were repeatable, and his measurements could be independently verified.
In 1616, the inquisition of the Catholic Church ordered Galileo not to hold or defend the Copernican position. He was tried and banned by the Inquisition in 1632, following the publication of "Dialogue Concerning the Two Chief World Systems."
The Church claims were that the book favoring Copernican theory and a non Geocentric model of the solar system.
Galileo was followed by several who would carefully measure and verify astronomical information.
Johannes Kepler (1571-1630)
Kelper was probably as much an astrologer as astronomer. Some of his theoretical work has been dismissed by modern astronomers (i.e. Music of the Spheres), with the possible exception of his three laws of motion.
First Law: All planets move in elliptical orbits with the Sun in one of the focii.
Second law: The area from the ellipse to the focus of the ellipse is proportional to time.
Third law: The cube of planetary orbit radius is proportional to the square of the orbital period
Rene' Descarte (1596 - 1650)
French mathematician, philosopher, and physicist. Best known for his statement "I think, therefore I am." The father of analytical geometry, the Cartesian coordinate system is named after him.
Christiaan Huygens (1629 – 1695)
Dutch Astronomer, noted for his argument that light consists of waves, now known as the Huygens–Fresnel principle. This principal became instrumental in the understanding of wave-particle duality. Having derived the equation for centripetal force, Huygens is seen as the first theoretical physicist to use formulae in physics.
Isaac Newton (1642 - 1727)
Newton followed in the tradition of Galileo (1564-1642), Descarte (1596 - 1650), Huygens (1629 – 1695), and Kepler (1571-1630). In his day, Newton was known as a "natural philosopher."
Newton developed the idea of Gravitation as the study of natural phenomena. While musing in a garden, the concept of gravity occurred to him, "which brought an apple from the tree to the ground," and Newton would later show that gravity also applies to the moon.
Notable is his work on celestial mechanics and his three laws of motion. His work was defined by mathematics and physics, having independently invented calculus. Some of Newton's work today would seem to border on superstition (for example, alchemy). Newton is noted for his his three laws of motion, the invention of the reflecting telescope, and his fundamental work in spectroscopy and light.
Newton's Laws of Motion:
1) A body at rest will remain at rest, and a body in motion will remain in motion unless influenced by an external force.
2) Force equals the mass times the acceleration (F = ma)
3) For every force that acts on a body, there is an equal and opposite force.
Joseph von Fraunhofer (1787–1826)
Mapping of Spectral lines. In 1814, Fraunhofer independently rediscovered the dark lines in the solar spectra, and began a systematic study and careful measurement of the wavelength of these features. In all, he mapped over 570 lines. (Modern observations of sunlight can detect many thousands of lines.) Fraunhofer is credited with the invention of the diffraction grating.
Fraunhofer died young, at the age of 39.
It was later discovered that the bright lines in the spectra are emission lines, and the dark lines of the spectra are absorption lines. Which is to say, a spectra shows which elements emit light, and which elements absorb light. This provides astronomers with information about the elements present on in a star or other celestial body.
Diagram for a diffraction grating
Albert Michelson (1852 – 1931)
Nobel Prize winner (1907). Known for his work on the measurement of the speed of light. Using an interferometer, determined that the speed of light is constant. He made extensive studies of the speed of light, which is today recognized as proof that there is no celestial "aether." His optical experiments served as a foundation to the theory of relativity.
Albert Einstein (1879 – 1955)
Nobel Prize winner (1921). Received a Nobel Prize for his discovery of the law of the photoelectric effect.
Using the knowledge that the speed of light is constant, he was able to combine idea of limits (from calculus) with the laws of conservation of energy and the law of conservation of momentum to develop the concepts of Special Relativity and General Relativity. Relativity continues to be used for scientific studies by astronomers today.
Erwin Schroedinger (1887 - 1961)
Shared the Nobel Prize with Dirac in 1933. Known for the Schrödinger's wave equation, which was a result of his dissatisfaction with the quantum condition in Bohr's orbit theory and his belief that atomic spectra should really be determined by some kind of eigenvalue problem. As did Einstein, Schroedinger worked on the problem of unifying gravitation and electromagnetism. Nuclear physics is now used by astronomers to explain the structure and composition of stars.
Edwin Hubble (1889 - 1953)
Although the "Red Shift" phenomena had been observed by a number of Astronomers, it was Hubble who first associated Red Shift with the luminosity of stars. Having developed Hubble's Law in 1929, the formula helped astronomers determine the age of the universe, and provided evidence that the universe was expanding. Hubble marks the point at which Astronomers began to associate Red Shift with distance to a star
You Tube video of the Michelson Morley interferometer:
- Extended Michelson-Morley Interferometer experiment.
You Tube video showing the Michelson Morley experiment using an interferometer. Michelson used this type of equipment to measure the speed of light.
Red Shift simulation
Radio telescopes were first invented by Karl Guthe Jansky in 1931. He designed it for the capturing of short radio waves. After him, Grote Reber invented the latest variations of dish and parabolic types of radio telescopes in 1937. Many types of telescopes were developed in the 20th century for a wide range of wavelengths from radio to gamma-rays.
Hawking's key scientific works to date have included (with Roger Penrose) theorems regarding gravitational singularities in the framework of general relativity, and the theoretical prediction that black holes should emit radiation, which is today known as Hawking radiation (or sometimes as Bekenstein-Hawking radiation).
Perhaps best known to astronomers for his work with Charles Misner and John Wheeler on "Gravitation," Kip Thorne has taught a generation of Astronomers the concepts behind the study of black hole phenomena. He is one of the world’s leading experts on the astrophysical implications of Einstein’s general theory of relativity.
Michel de Nostredame (Nostradamus) (1503 - 1566)
Best known for his book Les Propheties ("The Prophecies"), the first edition of which appeared in 1555. He used astrology to predict events in his "quatrains," but was heavily criticized by professional astrologers of the day for incompetence.
John Dee (1527 - 1608 )
British Astrologer, a follower of Cornelius Agrippa and occult philosophy. He studied astronomy, mathematics, geography, history and science. He wrote on the subjects of navigation, history, geometry, etc.
John Dee is said to have produced a horoscope for Sir Philip Sidney. It predicted that by the time Sir Sidney reached the age of 31, he would be in mortal danger from a sword or gunshot wound. Sir Sidney was killed on 17th October 1586, at the age of 31.
William Lilly (1602 - 1681)
British Astrologer. By 1634, Lilly had begun practicing astrology and other forms of the occult such as talismanic magic, invoking spirits and gazing at crystals.
Lilly published yearly prophetic almanacs, which were extremely popular. His first, titled Merlinus Anglicus Junior, published in 1644, foretold of the King's defeat at the Battle of Naseby in 1645. Later, he would be censored by the government.
Lilly is remembered as the principal authority of horary astrology (construction of a horoscope for astrological use).
Llewellyn George (1876 - 1954)
Founder of Llewellyn Publications (1901) in Portland, Oregon (USA). Known for printing astrological literature, it is an established name in the astrology community.
Marc Edmund Jones (1888 - 1980)
Astrologer, movie script writer, and author of pulp fiction and mystery stories. Also known as “The Cabalist,” later became an ordained Presbyterian minister. He published "The Sabian Symbols in Astrology," which gave the exact symbols and interpretative character for each of the 360 degrees of the zodiac found in the astronomical ecliptic.
Jeane Dixon (1904 - 1997)
Popular psychic and astrologer. Perhaps best known for her prediction in the May 13, 1956 issue of Parade Magazine. She said that the 1960 presidential election would be “dominated by labor and won by a Democrat. ” She went on to say that that Democratic president would be assassinated or die somehow while in office.
Jeane Dixon also warned actress Carole Lombard that it would be dangerous for her to travel by plane in January 1942, but the warnings were ignored. Carole Lombard would die in a plane crash during a storm.
For a period, she would make predictions for the coming year that were published in several tabloids. Many people made a game of pointing out any inaccurate predictions she made.
Jeane Dixon also began a syndicated horoscope column.
The development of a calendar is important to both Astrologers and Astronomers alike. In either profession, accuracy of the calendar becomes important to the results. If the calendar is not expressed correctly, then this introduces errors into the results.
Calendars have been developed in a number of different cultures, but the fundamental theme that needs to be recognized is that astronomical cycles are neither constant nor perfect.
The modern day calendar that we are familiar with in Western cultures is known as the Gregorian calendar, and differs from calendars developed by other cultures. For example, different calendars were also developed independently by the Chinese, Indians, Islam, Jewish, and Mayan (American) cultures. The Gregorian calendar is an arithmetic calendar, based upon counting the number of days as the basic unit of time. It is divided into 12 months, with the months having varying lengths. The 12 months make up a year.
The concept of the Gregorian calendar, then, is based upon the rotation of the Earth on its axis in one day, the revolution of the Moon around the Earth in one month, and the revolution of the Earth around the Sun in one year.
The Gregorian calendar was developed in 1582 in order to replace the Julian calendar, in an effort to correct errors in the Julian calendar. By the time that the Gregorian calendar was adopted in the United States, it was recognized to be off by 11 days. A correction of 11 days was made to the calendar in 1752 by Britain (and in what is now the United States). Russia and Greece changed to the Gregorian calendar in the 20th century.
Astronomers may express the calendar in terms of a Julian day, a Tropical Year, Siderial Year, or even the Atomic clock (i.e., International Atomic Time). In contrast, Astrologers often reference the calendar in terms of the signs of the Zodiac.
To illustrate how the complexity of calendars might cause confusion with results, Astrologers divide the Zodiac into 12 equal parts. This is different from Astronomers, who claim that there are 13 constellations along the ecliptic.
While Astrologers are concerned with 12 constellations, Astronomers are concerned with all constellations, about 88 in number. (Astronomers do not restrict themselves to the ecliptic, although it may be practical to do so for the purposes of a calendar.) Astronomers do not typically use the term "Zodiac," but Astrologers do continue to use the term "Zodiac." The term "Zodiac" originated from the Greek mythological word for the animal that could be traced out in the sky from the position of the stars (modern day astronomers call them constellations).
Throughout history, calendars were developed by different cultures to serve different needs. Although we normally think of calendars to describe years (as in the time it takes the earth to circle the Sun), most calendars usually exhibit some form of lunar cycles.
Since the publication of Einstein's "Special Theory of Relativity," astronomers have developed theories to explain the perception of dilation of time. Einstein had found that a limit on the speed of light had an impact upon known laws of physics. Later, he would develop his "General Theory of Relativity." Perhaps the most pertinent practical application of this has been used to explain the problem with the orbit of Mercury. The use of General Relativity has shown that the observable orbit (of the major axis) of Mercury slowly changes at a rate that is different from that which is predicted by Newton's equations. This is mainly due to Mercury's orbital speed (of about 30 miles/sec, or 48 km/sec). Nuclear physicists use relativity to describe the magnetic interaction of particles at high speeds.
Relativity has shown that time dilation occurs as you approach the speed of light. (That is, time will appear to slow down.) More recent theories show that the same type of time dilation phenomena also occurs in the vicinity of black holes.
Astrology has no credible theory about time dilation.
Astronomy (Western) Astrology (Western)
Giordano Bruno Nostradamus
Tycho Brahe Tycho Brahe
Gallileo William Lilly
Kepler Llewellyn George
Isaac Newton Marc Edmond Jones
Einstein Jonathan Cainer
Hubble Jeane Dixon
- Use of constellations ( 88 )
- Use of the signs of the zodiac ( 12 )
- States that stars have no significance in regard to human behavior
- States that stars predict fate or provide advice for human behavior
- Planets have no significance in regard to human behavior
- Planets predict fate or provide advice for human behavior
- Claims our moon has no significance in regard to providing advice for normal human behavior
- The moon predicts the fate of (or provides advice for) normal human behavior.
- Not generally used to advise farmers beyond the use of a calendar.
- Used to hatch chickens, butcher hogs, cure meat, or can food.
- Does not predict human behavior, and therefore has no measurement of human behavior.
- Attempts to predict human behavior, but makes no attempt to verify or measure the results.
- Does not advise the use of Astrology.
- May advise the use of Ephemeral tables produced by Astronomers.
- Requires higher mathematics, often well beyond one year of calculus.
- Does not require higher mathematics. Uses simple math or geometry, or calculations from astronomers can be used.
- Follows rigorous standards of other sciences, particularly physics.
- No scientific standard, considered to be an "art."
- Can obtain an accredited college degree in astronomy.
- Cannot obtain an accredited college degree in astrology.
- Typical results are repeatable, and requires equipment (such as a telescope) for measurement or verification.
- Typical results for behavior are not repeatable and does not require equipment for measurement or verification.
- Have made continuous improvements to measuring instruments, such as optical telescopes, radio telescopes, and diffraction gratings.
- Have not made improvements to measuring instruments in modern times.
- Discovered and measured the speed of light.
- Makes no attempts to measure light.
- May search for elements in spectra in order to determine the composition of stars or planets.
- May search for signs of feminine, masculine, fertile, barren, Earth, Air, water or fire.
- Authority for the modern calendar.
- Not an authority for the modern calendar.
- Used for space exploration.
- Uses the planets or moon as a guide through the four seasons.
- Have found planets in other solar systems.
- No discoveries with regard to other solar systems.
- Have modelled the creation, structure, and behavior of black holes
- Has no credible science on black hole phenomena.
- Used by NASA or other space agencies.
- NOT used by NASA or other space agencies.
- Has measured the speed of the Sun around the Milky Way to be about 250 km/sec. (Over ten times faster than the motion of the Earth around the Sun.)
- Astrology has no statement about impact of the motion of the Sun, the Milky Way, or any other galaxy.
- Has measured that the motion of the Milky Way through the Local Supercluster is more than five times faster than our Sun around the Milky Way. (i.e., Virgo infall plus the mean velocity of the Virgo cluster.) That is, Relativity and Red Shift measurements have enabled Astronomers to measure our speed through the Universe up to (arguably) 3 million miles per hour, or 1460.0 km/sec.
- Astrology has no statement about the impact of the motion of the Milky Way, the Virgo cluster, the Local Group, or the Leo / Hydra--Centaurus Supercluster (or Local Supercluster).
The differences regarding the inclusion of other disciplines:
- Celestial mechanics (use of Newton's laws to predict the motion of celestial bodies).
- Numerology (The study of how numbers may provide information about human behavior.)
- Astrophysics (physical laws of celestial bodies)
- Palmistry (The study of how lines in the human hand may provide information about human behavior.)
- Nuclear physics (the study of atomic phenomena in order to understand the structure of stars).
- Kabbalah (or Caballah) - the study of how letters of the alphabet (Jewish esoterics) may provide information about human behavior.
- Chemistry (the use of the spectra in order to understand the chemical composition of stars.)
- Before the development of the science of chemistry, astrologers were also known to practice alchemy.
- Astronomy (may use astronomical ephemeral tables, that are published by astronomers)
- Cosmology (the study of the structure of the universe)
Astrology presumes that the stars, planets, or moon have an influence upon human existence.
Astronomy presumes that the stars, planets, or moon have NO influence upon human existence.
Astronomers have been using calculus in the study of the motion of celestial bodies since the days of Isaac Newton.
Astrologers do not require an understanding of calculus.
University students that major in astronomy are also expected to major in physics. This is because it is important for astronomers to also understand physics.
University students cannot major in astrology at a University. This is because astrology is not considered to be a science. Also, an undergraduate major in physics is not required to become an astrologer.
It is possible to obtain an accredited college degree in Astronomy.
It is NOT possible to obtain an accredited college degree in Astrology.
Admittedly, majoring in Astronomy in college, I have no inclination to study Astrology. Therefore, this article is by default, biased. Also, for the purposes of this article, I have only followed the development of Astrology and Astronomy in the Western tradition. This article does not follow the development of either Astrology or Astronomy in other cultures, such as China, India, or the Middle East.
Human behavior is today more effectively explained by psychology, sociology, medicine (such as treatment for mental disorders). Events that affect human behavior are now more effectively explained by meteorology (i.e., weather), geology, or oceanography. There is no evidence to support Astrology as it relates to human events.
Astronomy makes no attempt to associate the stars, planets, or moon with effects upon human behavior. Astronomy is the pursuit of the study of natural laws with regard to celestial bodies. Astronomers can tell you how fast an apple may fall from a tree, or how much energy it would take for a trip to the moon. An Astronomer may be able to tell you if an asteroid is headed toward the earth. Astronomers make no association of the stars, planets, or moon to human behavior.