Categories: Astronomy HistoryFAQs

How do Astronomy and Astrology Differ?


Because their similarity doesn’t just end with the way they sound, the disciplines of ‘astronomy’ and ‘astrology’ often confuse many people! Indeed it is pertinent to mention that they both share a deep connection with the celestial heavens, and that both studies continue to increase in popularity with each passing year. For instance, Kasamba’s astrologers have performed more than 3 million readings since the site’s inception, while popular astronomy site Space.com attracts millions of unique visitors each month, and that number is likely to only grow in the future.


“Astronomers examine the positions, motions, and properties of celestial objects. Astrology attempts to study how those positions, motions, and properties affect people and events on Earth.” (skyandtelescope.com).


It’s astrology that tells you what kind of day you will have every time you go through that ‘horoscope’ section in your newspaper, while modern-day astronomy has nothing at all to do with human behaviour. In other words, there is no way you can imagine an astrologer working at NASA! Astrology is more of a pseudo-science that revolves around the belief that the position of planetary objects such as the Sun, Moon and planets during an individual’s birth have a major role in the determination of an individual’s present and future. In addition to horoscopes, the field of astrology extends to tarot cards, psychic reading, numerology, and palmistry. Astrology, however, makes no attempt to measure its predictive human behavior results, and not being a science means that there are no accredited degrees in the subject offered by universities.


Astronomy is a natural science that studies celestial phenomena and objects in the universe, and the processes that govern their life cycles. As such, it is possible to obtain an accredited college degree in the subject, and university students that major in astronomy are also expected to have an aptitude for physics and mathematics. They will also encounter a range of other related scientific subjects during their studies, including celestial mechanics, astrophysics, nuclear physics, chemistry, biology, geology, and cosmology.

Astronomy makes no attempt to link human behavior and terrestrial events with what is taking place beyond the earth’s atmosphere. Instead, scientists believe that human behavior is better understood through the study of psychology, sociology, and medicine; while human events are more directly influenced by meteorology, geology, or oceanography. Finally, astronomy rigorously attempts to measure and verify its findings, and over the years has devised many instruments to aid in this pursuit, including optical telescopes, radio telescopes, and diffraction gratings.

Communal Roots

Although astronomy is a science, and astrology is considered an ancient belief system, they both share historical roots and it wasn’t until the 17th century that a definitive split took place between these studies. This is best understood in a historical context, as religion has exerted a powerful influence over the way science was allowed to develop throughout the history of mankind. Nevertheless, both practices share common roots and for millenia one of the main driving forces for improvements in astronomy was the desire of astrologers to produce more accurate future predictions.


After a conscious effort was made to measure, record, and foretell the seasons, and importantly determine the right time of year for people to plant or harvest their crops, astrology became the means by which to predict the recurrence of various celestial events. Ancient people also believed that their gods lived amongst the stars, and each night when they looked up to the sky, they would make observations of the celestial bodies, wonder as to their origin, and create stories associated with their religious beliefs. In addition to studying the movements of the Sun, Moon, and planets, over time the stars were organized into constellations, with those appearing in the sun’s path (ecliptic) arranged into twelve 30 degree divisions known as the zodiac. Astrologers assert that whatever zodiac constellations the Sun appears in an at the time of a person’s birth will then determine their personalities.


In the East, India and China developed intricate systems for using the position of the planets and stars to foretell the future. In the West, astrology originated in Mesopotamia around 1950 BCE with its influence then spreading westwards to Ancient Greece following the conquest of Asia during the reign of Alexander the Great (336–323 BCE), before the practice traveled on towards Rome, the rest of Europe, and the Middle East.

In Mesopotamia, the ancient Babylonians were famed for their knowledge of the heavens, although back then astrologers were not assigned separate roles for predicting celestial phenomena (astronomy), or interpreting their divine meaning (astrology); both functions were performed by astronomer-priests. By observing and interpreting the movements of their gods represented by the Sun (Shamash), Moon (Sin), and the five planets of Jupiter (Marduk), Venus (Ishtar), Saturn (Ninurta), Mercury (Nabu), and Mars (Nergal), a Babylonian priest could apparently divine what the gods were planning.

From 600 to 130 BCE, the Greeks transformed astronomy from a religious observational study into a theoretical science whose prime concern was discovering the structure of the universe. Nevertheless, astrology continued to enjoy popular support and was commonly practised throughout history, with its acceptance or rejection fluctuating with the fashion and taste of royal courts and other powerful figures of the era. By the 17th century and the ‘Age of Reason’, however, astrology fell out of favor with the intellectual elite who increasingly viewed the practice as superstition, and lacking any evidential support.


In the absence of supporting scientific evidence, questions have been raised on the academic and theoretical validity of astrology. More recently, the commercial nature of the practice of astrology and artificial claims to control life events has led to its further criticism. Scientists frequently contradict the claims and predictive value of astrologers, although one cannot completely dismiss the observations of the stars as these are usually based on careful records, or calculations from astronomers. If the predictions of astrologers are to be taken more seriously, however, then they will first have to produce more verifiable tests to measure their effectiveness. In the meantime, to most people astrology and horoscopes will continue to be thought of as a bit of harmless fun and entertainment.

Peter Christoforou :