An image of the sun surrounded by a calendar showing seasons and the symbols of the zodiac that appear on the title page of an 1814 almanac written by Nathanael Low, M.D., and published by Munroe and Francis in Boston, Mass.

In astrology, the position of the sun within a Zodiac sign (between 0° and 30°) is of importance in the reading. That is why you should know not only your sign, but the degree within that sign. So, I hope you find this tool useful for your further understanding of astrology and the meaning of your Zodiac sign. Astrology, in its broadest sense, is the search for human meaning in the sky; it seeks to understand general and specific human behavior through the influence of planets and other celestial objects. Known as Hindu or Indian astrology, this branch of astrology deals with the influence of the stars and planetary motions or positions subject to the time and effects on Humans. According to it, there are 12 zodiacs, 9 planets, 12 houses, and 27+1 constellations that need to be observed for making a native’s birth chart or natal chart.

As the summer officially begins, with the Summer Solstice occurring in the Northern Hemisphere on Thursday, those who enjoy Western astrology will be checking out their Summer Solstice horoscopes to try to use the stars to figure out what the season might have in store.


While some horoscopes sites may promise predictions based on the “movement” of the stars, it’s important to remember that it’s the Earth that’s moving, not the stars. The reason why stars look like they’re moving, both throughout the night and over the course of the year, is because the Earth rotates on its axis and orbits around the Sun. But, before most humans knew that, they spent a lot of time thinking about what was happening up there in the sky.

So, though astrology — looking for answers, signs and predictions in the movements of the celestial bodies —isn’t itself a science, there’s a long history of humans looking up at the stars to plan their lives. Farmers used the skies as a calendar as long ago as Ancient Egyptians, when the rising of Sirius, the Dog Star, around mid-July, was seen as a marker of the imminent annual flooding of the Nile. Travelers used the skies as a compass, following the stars to know where to go. And many people used the skies as a source of mystical direction, too.


But who first looked up at the sky to make sense of what was happening down on the ground and why their fellow humans were behaving in certain ways? Exactly who came up with this way of thinking and when is unclear, but historians and astronomers do know a bit about how it got so popular today.

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Where did zodiac signs come from?

The stars are just one of the many things in the natural world that human beings have turned to for answers over the years.

“We don’t really know who first came up with the idea for looking at things in nature and divining influences on humans,” says astronomer Sten Odenwald, the director of Citizen Science at the NASA Space Science Education Consortium. “There’s some indication that cave art shows this idea that animals and things can be imbued with some kind of spirit form that then has an influence on you, and if you appease that spirit form, then you will have a successful hunt. That was taken over by the idea of divination, where you can actually look at things in nature and study them carefully, such as tea-leaf reading.”

Some form of astrology shows up in various belief systems in ancient cultures.

In Ancient China, noblemen looked at eclipses or sunspots as portents of good or bad times for their emperor, though it’s thought that those signs had less application to the lives of other individuals. (Odenwald points out that in societies where people in the lower classes had less control over their lives, divination could seem pointless.) The Sumarians and Babylonians, by around the middle of the second millennium BC, appeared to have had many divination practices — they looked at spots on the liver and the entrails of animals, for example — and their idea that watching planets and stars was a way to keep track of where gods were in the sky can be traced to The Venus tablet of Ammisaduqa. This tablet, which is dated to the first millennium BC and tracks the motion of Venus, is one of the earliest pieces of what’s been called Babylonian planetary omens. The ancient Egyptians contributed the idea that patterns of stars made up constellations, through which the sun appears to “move” at a specific times during the year.

It’s thought that all of these ideas came together when Alexander the Great conquered Egypt around 330 BC. Venus rules what in astrology.

“There must have been a lot of exchange that got the Greeks on-board with the idea of divination using planets,” says Odenwald, and because they were deep into mathematics and logic, they worked out a lot of the rules for how this could work.”

Here’s how NASA has described how that logic led to the creation of the familiar zodiac signs known today:

What are the 12 signs of the zodiac?

It was during this Ancient Greek period that the 12 star signs of the zodiac with which many people are likely familiar today — Aries (roughly March 21-April 19), Taurus (April 20-May 20), Gemini (May 21-June 20), Cancer (June 21-July 22), Leo (July 23-Aug. 22), Virgo (Aug. 23-Sept. 22), Libra (Sept. 23-Oct. 22), Scorpio (Oct. 23-Nov. 21), Sagittarius (Nov. 22-Dec. 21), Capricorn (Dec. 22-Jan. 19), Aquarius (Jan. 20 to Feb. 18) and Pisces (Feb. 19 to March 20) — were set down. These Western, or tropical, zodiac signs were named after constellations and matched with dates based on the apparent relationship between their placement in the sky and the sun.

The Babylonians had already divided the zodiac into 12 equal signs by 1500 BC — boasting similar constellation names to the ones familiar today, such as The Great Twins, The Lion, The Scales — and these were later incorporated into Greek divination. The astronomer Ptolemy, author of theTetrabiblos, which became a core book in the history of Western astrology, helped popularize these 12 signs.

“This whole idea that there were 12 signs along the zodiac that were 30° wide, and [that] the sun moved through these signs regularly during the year, that was codified by Ptolemy,” says Odenwald. Even the word “zodiac” comes from the Greek, from a term for “sculpted animal figure,” according to the Oxford English Dictionary, and the order in which the signs are usually listed comes from that period too.

“Back at the time of the Greeks,” Odenwald explains, “the first day of spring started when the sun appeared in the constellation Aries and then everything was marked from that time forward around the circuit of the year.”

However, the Earth has moved on its axis since then, a process known as precession, so now the dates that are used to mark the signs don’t really correspond to the background constellations that give them their signs names. In fact, the chronology has really shifted one sign to the West. That means zodiac sign dates, based on the mathematical division of the year, basically correspond today to the presence of the sun in the constellations of the signs that come before them. (The set nature of the signs is also why the Minnesota Planetarium Society’s 2011 argument that there should be a 13th zodiac sign now, Ophiuchus, didn’t actually result in a big astrology change.)

“Before, astrologers looked at where the sun was relative to background constellations in general, and that generally matched up almost exactly with the signs of zodiac defined by Ptolemy,” says Odenwald. “Now astrologers do their calculations and forecasting based on where the planets and the sun are relative to the 12 signs —which are fixed — and not based on where they are relative to the constellations. Astrologers say if the sun is in the sign of Sagittarius on the day you were born, then you’re a Sagittarius.”

Read More: Mercury Is Entering Retrograde Again. This Is Why So Many People Care

What’s the difference between astrology and astronomy?

For centuries, astrology (looking for signs based on the movement of the celestial bodies) was considered basically the same thing as astronomy (the scientific study of those objects). For example, revolutionary 17th-century astronomer Johannes Kepler, who studied the motion of the planets, was at the time considered an astrologer. That changed around the beginning of the Enlightenment in the late 17th century.

Once Sir Isaac Newton basically turned the sky into a calculator, mathematizing the motion of the planets and realizing that gravity controlled everything, Odenwald says, “that started a whole new scientific approach to looking at the sky and the motion of planets and the earth.”

That’s the point at which astronomy came to be known as a science and astrology was acknowledged as not a science. But its popularity relies on factors that numbers can’t compute, and the appeal of looking to the stars for answers has not waned — in fact, in recent years, it seems to have expanded. After all, a 2014 National Science Foundation poll found more than half of millennials think astrology is a science.

And Odenwald argues that, even if astrology’s answers aren’t based on scientific study, the reason people keep turning to the sky does come down to something very real — a psychological phenomenon he calls the human tendency for “self-selection,” the search for interpretations that match what we already hope to be true.

“People magnify the positives, they forget the negatives,” he says, “and that’s just how we’re designed.”

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  • Nature and significance
  • Historical development
    • Astrology after the Hellenistic period

The original purpose of astrology, on the other hand, was to inform the individual of the course of his life on the basis of the positions of the planets and of the zodiacal signs (the 12 astrological constellations) at the moment of his birth or conception. From this science, called genethlialogy (casting nativities), were developed the fundamental techniques of astrology. The main subdivisions of astrology that developed after genethlialogy are general, catarchic, and interrogatory.

General astrology studies the relationship of the significant celestial moments (e.g., the times of vernal equinoxes, eclipses, or planetary conjunctions) to social groups, nations, or all of humanity. It answers, by astrological means, questions formerly posed in Mesopotamia to the bāru.

Catarchic (pertaining to beginnings or sources) astrology determines whether or not a chosen moment is astrologically conducive to the success of a course of action begun in it. Basically in conflict with a rigorous interpretation of genethlialogy, it allows the individual (or corporate body) to act at astrologically favourable times and, thereby, to escape any failures predictable from his (or its) nativity.

Interrogatory astrology provides answers to a client’s queries based on the situation of the heavens at the moment of his posing the questions. This astrological consulting service is even more remote from determinism than is catarchic astrology; it is thereby closer to divination by omens and insists upon the ritual purification and preparation of the astrologer.

Other forms of astrology, such as iatromathematics (application of astrology to medicine) and military astrology, are variants on one or another of the above.

Historical development

Astral omens in the ancient Middle East


The astral omens employed in Mesopotamian divination were later commingled with what came to be known as astrology in the strict sense of the term and constituted within astrology a branch described as natural astrology. Though lunar eclipses apparently were regarded as ominous at a somewhat earlier period, the period of the 1st dynasty of Babylon (18th to 16th centuries bc) was the time when the cuneiform text Enūma Anu Enlil, devoted to celestial omina, was initiated. The final collection and codification of this series, however, was not accomplished before the beginning of the 1st millennium bc. But the tablets that have survived—mainly from the Assyrian library of King Ashurbanipal (7th century bc)—indicate that a standard version never existed. Each copy had its own characteristic contents and organization designed to facilitate its owner’s consultation of the omens.

The common categories into which the omens of Enūma Anu Enlil were considered to fall were four, named after the chief gods involved in the ominous communication: Sin, Shamash, Adad, and Ishtar. Sin (the Moon) contains omens involving such lunar phenomena as first crescents, eclipses, halos, and conjunctions with various fixed stars; Shamash (the Sun) deals with omens involving such solar phenomena as eclipses, simultaneous observations of two suns, and perihelia (additional suns); Adad (the weather god) is concerned with omens involving meteorological phenomena, such as thunder, lightning, and cloud formations, as well as earthquakes; and Ishtar (Venus) contains omens involving planetary phenomena such as first and last visibilities, stations (the points at which the planets appear to stand still), acronychal risings (rising of the planet in the east when the Sun sets in the west), and conjunctions with the fixed stars.

Though these omens are often cited in the reports of a network of observers established throughout the Assyrian empire in the 7th century bc, they seem to have lost their popularity late in the period of the Persian domination of Mesopotamia (ending in the 4th century bc). During the later period new efforts were made, in a large number of works called Diaries, to find the correct correlations between celestial phenomena and terrestrial events. Before this development, however, portions of the older omen series were transmitted to Egypt, Greece, and India as a direct result of Achaemenid domination (the Achaemenian dynasty ruled in Persia from 559 to 330 bc) of these cultural areas or of their border regions.

Astral omens in Egypt, Greece, India, and China

The evidence for a transmission of lunar omens to Egypt in the Achaemenian period lies primarily in a demotic papyrus based on an original of about 500 bc. A more extensive use of Mesopotamian celestial omens is attested by the fragments of a book written in Greek in the 2nd century bc and claimed as a work addressed to a King Nechepso by the priest Petosiris. From this source, among others, the contents of Enūma Anu Enlil were included in the second book of the Apotelesmatika, or “Work on Astrology” (commonly called the Tetrabiblos, or “Four Books”), by Ptolemy, a Greek astronomer of the 2nd century ad; the first book of an astrological compendium, by Hephaestion of Thebes, a Greco-Egyptian astrologer of the 5th century ad; and the On Signs of John Lydus, a Byzantinebureaucrat of the 6th century. Yet another channel of transmission to the Greeks was through the Magusaeans of Asia Minor, a group of Iranian settlers influenced by Babylonian ideas. Their teachings are preserved in several Classical works on natural history, primarily that of Pliny the Elder ( 23–79), and the Geoponica (a late collection of agricultural lore).


What Is Astrology Mean

In various Middle Eastern languages there also exist many texts dealing with celestial omens, though their sources and the question as to whether they are directly descended from a Mesopotamian tradition or are derived from Greek or Indian intermediaries is yet to be investigated. Of these texts the most important are those ascribed to Hermes Trismegistos by the Harranians and now preserved in Arabic, the Book of the Zodiac of the Mandaeans (a Gnostic sect still existing in Iraq and Khuzistan), the Apocalypse, attributed to the biblical prophet Daniel (extant in Greek, Syriac, and Arabic versions), and The Book of the Bee in Syriac.

The transmission of Mesopotamian omen literature to India, including the material in Enūma Anu Enlil, apparently took place in the 5th century bc during the Achaemenid occupation of the Indus valley. The first traces are found in Buddhist texts of this period, and Buddhist missionaries were instrumental in carrying this material to Central Asia, China, Tibet, Japan, and Southeast Asia. But the most important of the works of this Indian tradition and the oldest extant one in Sanskrit is the earliest version of the as-yet-unpublished Gargasamhita (“Compositions of Garga”) of about the 1st century ad. The original Mesopotamian material was modified so as to fit into the Indian conception of society, including the system of the four castes and the duty of the upper castes to perform the samskaras (sanctifying ceremonies).

What Is Astrology Club

There are numerous later compilations of omens in Sanskrit—of which the most notable are the Brhatsamhita, or “Great Composition,” of Varahamihira (c. 550), the Jain Bhadrabahu-samhita, or “Composition of Bhadrabahu” (c. 10th century), and the Parishishtas (“Supplements”) of the Atharvaveda (perhaps 10th or 11th century)—though these add little to the tradition. But in the works of the 13th century and later, entitled Tājika, there is a massive infusion of the Arabic adaptations of the originally Mesopotamian celestial omens as transmitted through Persian (Tājika) translations. In Tājika the omens are closely connected with general astrology; in the earlier Sanskrit texts their connections with astrology had been primarily in the fields of military and catarchic astrology.