The western zodiac, which consists of 12 constellations: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces, is one such tradition.
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What are the 12 zodiac constellations?
Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius, and Pisces are the 12 zodiac constellations, and you’re definitely familiar with them thanks to astrology.
What do the constellations of the zodiac signify?
First and foremost, you have our permission to refer to yourself as a Lupus or a Lyra. People form attachments to a variety of constellations, not just those in the “zodiac.” Out of the 88 zodiac constellations officially classified by the International Astronomical Union, we acknowledge 13 of them. The Zodiac constellations are the ones that the Sun appears to travel through throughout the year. Of However, because the Earth revolves around the Sun and hence the Sun’s position relative to the background stars changes constantly, this motion is illusory.
The Sun appears to be travelling through Virgo the Maiden right now. The Sun will enter Libra, the Scales, at the end of October. The Sun then travels through Scorpius the Scorpion, Ophiuchus the Serpent Charmer, Sagittarius the Archer, Capricornus the Seagoat, Aquarius the Water Bearer, Pisces the Fish, Aries the Ram, Taurus the Bull, Gemini the Twins, Leo the Lion, and finally back to Virgo the Maiden, where the cycle begins again.
The Sun happened to pass through these thirteen constellations because they were oriented in such a way. We could change Earth’s orbit so that the Sun seems to pass through different constellations if we wanted to (and had supernatural powers). Lupus and Lyra, on the other hand, cannot be zodiac constellations because the Sun does not “travel through” them.
If the Sun was in that constellation when you were born, you were termed a “Virgo” or “Leo.” The astrological calendar, on the other hand, does not account for precession. The constellations aligned along the Sun’s path, called the ecliptic, shift stations slowly over time, by about one degree every 73 years, as the Earth’s poles precess over a 26,000-year period. The dates associated with the zodiac by astrologers were valid roughly 2,000 years ago. On the first day of Spring, for example, the Sun was in Aries. It is now in the sign of Pisces. As a result, astronomers continue to refer to the “First Point of Aries” on the first day of Spring (Vernal Equinox).
Where are the constellations of the zodiac?
You’ve probably heard of constellations, and we’ve discussed them before on this blog. A constellation is a group of stars in the sky that have been given a name and are arranged in a certain pattern. The most well-known constellations, such as Cassiopeia, Hercules, Pegasus, and Ursa Major, are mostly from the classical Greek tradition. None of these constellations, however, are part of the zodiac.
The zodiac constellations will undoubtedly ring a bell. Most of us are familiar with the signs Gemini, Leo, Sagittarius, and Scorpio. They form a pattern in the sky when combined with the other Zodiac constellations, which total twelve. Astronomers have utilized this pattern for centuries because it makes it easier for observers to trace the movement of the solar system and stars throughout the year.
In other words, the zodiac constellations create a two-dimensional sky map that is extremely useful for navigation. It made it easier for ancient astronomers to locate things and explain their positions in the sky, as well as travelers and sailors who rely on the stars to navigate.
The zodiac’s twelve constellations are aligned along the ecliptic’s plane. The circular journey of the Sun across the sky as seen from Earth defines the ecliptic. In other words, throughout the course of a year, the Sun appears to traverse through these constellations. The Sun’s trip across the zodiac was utilized by ancient cultures to determine the time of year because of this consistent cycle. The zodiac’s cardinal constellations (Aries, Cancer, Libra, and Capricorn) mark the start of the four seasons in this fashion. On the first days of spring, summer, autumn, and winter, the Sun enters these constellations.
In reality, in ancient Greek, the word Zodiac means “circle of animals” or “circle of life.” This helps to explain why the majority of the constellations are depicted as animals or legendary beings. Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius, and Pisces are the 12 zodiac constellations. All of these, as well as the whole round of the zodiac, are plainly visible among other constellations in modern star maps.
But when does each zodiac constellation become more apparent during the year, and what do they represent?
What are the names of the seven primary constellations?
We chose seven of the most well-known constellations from both the Northern and Southern hemispheres for this infographic: Ursa Major, Cassiopeia, Orion, Canis Major, Centaurus, Crux, and Carina. You can simply locate any of these constellations in the sky using our short suggestions. Any amateur astronomer who wants to learn about notable constellations and asterisms will find our infographic useful. If you like this infographic, please share it with your friends! It’s also on Instagram, where you can find it (along with our other infographics) using the hashtag #infographics StarWalk. For more information about stargazing, follow us on Instagram!
Are the signs of the zodiac based on constellations?
Early astronomers witnessed the Sun passing through the Zodiac signs in a year’s time, spending roughly a month in each. As a result, they determined that each constellation covers 30 degrees of the ecliptic.
However, due to a phenomenon known as precession, the positions of the constellations we see now have changed.
The zero point of the Zodiac used to designate the beginning day of spring in the Northern Hemisphere. The vernal equinox happens when the ecliptic and celestial equator collide, according to astronomers.
The zero point existed in Aries around 600 BCE, and it was known as the “first point of Aries.” (See Figure 1). The constellation Aries covered the first 30 degrees of the ecliptic; Taurus covered the next 30 degrees; Gemini covered the next 60 degrees; and so on for all twelve constellations of the Zodiac.
The Earth wobbles around its axis in a 25,800-year cycle, which ancient astrologers were unaware of. The gravitational attraction of the Moon on Earth’s equatorial bulge causes this wobble, which is known as precession.
This wobble has led the junction point between the celestial equator and the ecliptic to migrate west along the ecliptic by 36 degrees, or nearly one-tenth of the way around, over the past two and a half millennia. This indicates that, in relation to the stars beyond, the signs have moved a tenth of the way across the sky to the west, or about a month.
For example, persons born between March 21 and April 19 are considered Aries. During much of that time, the Sun was no longer in the constellation of Aries. The Sun is actually in the constellation of Pisces from March 11 to April 18! (See Illustration 2) See also Figure 3, which depicts the equinox precession from 600 BCE to 2600 CE.
The dates when the Sun is truly within the astronomical constellations of the Zodiac, as defined by contemporary constellation borders and corrected for precession, are listed in the table below (these dates can vary a day from year to year).
When precession is taken into consideration, your zodiac sign will most likely be different. And if you were born between November 29 and December 17, your zodiac sign is one you’ve never heard of before: Ophiuchus! After Scorpius, the eliptic crosses across the constellation of Ophiuchus.
Check out your “actual” zodiac sign below, and visit the Birthday Sky program to see what the sky looked like on your birthday.
Scorpio belongs to which constellation?
In astronomy, Scorpius (Latin: “Scorpion”), sometimes known as Scorpio, is a zodiac constellation that lies between Libra and Sagittarius in the southern sky, at roughly 16 hours 30 minutes right ascension and 30 south declination.
What is the largest zodiac constellation?
With dozens of confirmed exoplanets and at least a dozen Messier objects, Virgo is a dense constellation. It is the Zodiac’s largest constellation, as well as the second-largest overall, after Hydra.
What makes the 12 zodiac constellations so unique?
The 12 signs of the zodiac, as mentioned in a horoscope, are inextricably linked to the Earth’s motion through the sky. The constellations that point out the path that the sun appears to take during the year provide us with these indicators. Dates in a horoscope may appear to match to when the sun travels through each constellation. They don’t always agree, though, because astrology and astronomy are two separate systems. Plus, a closer look at the Earth, the sun, and the stars reveals that the zodiac is more complicated than you might think!
The sun’s motion through the constellations
The sun appears to pass in front of numerous constellations as Earth revolves the sun. The sun’s position in relation to distant background stars drifts in an easterly direction from day to day, much how the moon appears in a little different spot in the sky each night. It’s not as if the sun isn’t moving. Its movement is totally fictitious, owing to Earth’s own rotation around our star.
The sun appears to be in front of, or “in,” different constellations throughout the year. The sun appears in Gemini one month and Cancer the next. The dates in the newspaper’s horoscope indicate when the sun is in a specific astrological sign. For example, the sign Aries is represented by the period between March 21 and April 19. However, your astrological sign does not always indicate which constellation the sun was in when you were born.
Why the zodiac constellations don’t always align with astrological signs
We need to know a little bit more about how the Earth moves to explain why constellations no longer coincide with their respective signs. We must also discuss how we measure time.
Time is a fiendishly difficult concept to grasp, especially if we insist on using the sun and stars as our point of reference. For better or worse, our calendar is based on the seasons. The day the sun appears at its most northerly point in the sky is June 21 – the approximate date of the summer solstice north of the equator and the winter solstice south of the equator. The North Pole is most inclined towards the sun at the June solstice.
The fact that the North Pole does not always point in the same direction as the background stars complicates things. Our world whirls around like a top. The Earth, like a top, wobbles! The North Pole traces a circle on the celestial sphere due to the Earth’s wobble. The wobbling is slow; it takes 26,000 years to complete one rotation. However, as time passes, the effect becomes more pronounced.
The direction of the Earth’s axis drifts somewhat throughout the course of one orbit around the sun. This means that the location of the solstice along our orbit changes by a very modest amount. The solstice occurs around 20 minutes before one full trip in front of the background stars!
Our drifting calendars
Because we base our calendar on the solstices and equinoxes (and astrologers on the signs), the Earth does not complete an orbit in a single year. The tropical or seasonal year is really a fraction of a second shorter than one full orbit (sidereal year). This means that the sun’s position relative to the stars on any given day say, June 21 wanders a very small amount each year.
However, after 2,000 years, the sun will be in a completely other constellation!
The sun was nearly halfway between Gemini and Cancer on the June solstice 2,000 years ago. The sun was between Gemini and Taurus on the June solstice fourteen years ago. In the year 4609, the June solstice point will move from Taurus to Aries, leaving Taurus behind.
When humanity formed the present Western zodiac some 2,000 years ago, the signs were roughly aligned with their respective constellations. However, the steady wobble of the Earth’s axis has led the solstice and equinox locations to shift around 30 degrees westward relative to the constellations in the intervening ages. Signs and constellations are currently around one calendar month off. They’ll be approximately two months away in another two thousand years or so.
Modern constellations and the zodiac
To make matters even more complicated, unlike astrological signs, constellations are not all the same size and shape. For the most part, the stars that make up a constellation are not physically related. They’re simply based on patterns that our forefathers noticed when they looked up at the sky, trying to make sense of it all.
The International Astronomical Union (IAU) established the constellations as sky regions, not only star patterns, in 1930. They established the boundaries we use today as a result of this. These current constellations are based on those introduced in the second century CE by Greek astronomer Ptolemy. He, in turn, took them from Babylonian scriptures dating back thousands of years. Throughout history, several societies have seen patterns in the sky that are unique to them. Some constellations are shared by many cultures (Orion is a good example), but not all.
There are actually 13 constellations that lay along the path of the sun, based on the present borders. Ophiuchus, the Serpent Bearer, sits between Sagittarius and Scorpius and is not mentioned in any horoscope. The signs stay stable in relation to the solstices and equinoxes, while the solstices and equinoxes shift westward in relation to the constellations or backdrop stars.
While the zodiac isn’t a fantastic predictor of love, fortune, or health, it is an excellent tool for better understanding the sun’s, Earth’s, and even the cultures that have come and gone on our small planet. The zodiac signs, which are drawn from constellations that line the path of the sun in the sky, trace Earth’s orbit and wobble and serve as a reminder of astronomy’s humble beginnings.
Bottom line: While you may identify the term zodiac with astrology, it also has a prestigious role in astronomy. The 12 constellations that make up the zodiac are located along the sun’s annual motion across the sky.