Zodiac Shift: Fact or Fiction?

While surfing through some astronomy websites yesterday, suddenly one sentence drew my attention. It was talking about the shift in zodiac signs. By that time, I had started receiving questions from people about it.

I told them simply, that it was JUST correct information, but it was not being presented with all the facts. It’s just being told to everyone that the zodiacs have shifted, by why this has happened was needed to be told.

When the number of questions went on rising, I thought to make a clarification, so in further lines; I will try to clarify to all of you about this new zodiac sign thing.

We’ll first have to check out what Astrology really is and what systems are used in Astrology.

According to Merriam-Webster Dictionary, Astrology is defined as “the divination of the supposed influences of the stars and planets on human affairs and terrestrial events by their positions and aspects”.

As we can see, Astrology is a method which uses positions of stars, and claims to predict the future events and also to know about the events which were or are being experienced by any human being at any given time.

Astrology is very old methodology. It dates back to almost 1st millennium B.C. There are two systems of Astrology which are used commonly nowadays, one is Eastern and other is Western. Eastern Astrology is also called Jyotish, Sidereal, or Vedic Astrology while Western is also known as Tropical Astrology.

The sky is divided into 88 constellations, or 88 parts. When the Earth moves around the Sun; the Sun, the Moon and the Planets appear to pass through 13 constellations. These 13 constellations are called Zodiacs and the line which is followed by the Sun, Moon and Planets is called “The Line of Ecliptic”. If we study it astronomically, then the Zodiacs are 13 but Astrologers always consider 12 Zodiacs. But we will not discuss it for the time being.

Line of Ecliptic shown to pass through the Zodiac Constellations

As you can see in the above image, the Ecliptic (dark red line) passes through all the Zodiacs (boundaries shown in red), and all the Planets, Moon and the Sun appear to travel along with the Ecliptic.

Western and Eastern Astrology are quite different from each other. The difference in both is that the Western Astrology is based on the Tropical Zodiac system, while Eastern relies on Sidereal Zodiac system.

Tropical Zodiac is a fixed system. On March 21, on Vernal Equinox, the year of Tropical Zodiac starts from Aries. 2500 years ago, when the Zodiac system was developed, the Sun used to be in the Constellation Aries from 20th March to 20th April.

Every day as the Sun appears to rise from East and set in the West, it actually follows a defined path which is called the Ecliptic. The Ecliptic passes through 13 Constellations out of 88. Therefore 13 zodiacs are there. The Sun spends a few days in each of these Zodiacs throughout the year. In the image below, you will find that on 1 April, 0 A.D, the Sun was in the Constellation Aries.

The Sun is shown to pass through the Constellation Aries on 1 April, 0000.

People at that time observed the movement of the Sun throughout the year and then exact dates were assigned to every Zodiac. And Tropical Zodiacs still follow the same dates. But are these dates still correct? Does the Sun pass through Aries today on the same dates?

Astronomically, when we study the apparent movement of Sun through the constellations of Zodiac, the Sun is in the Constellation Aries from April 18 to May 13. This is because, over the cycle of 25,700 years, the axis of Earth slowly wobbles like a spin top, which causes the change in the apparent position of constellations and the Zodiac system. This wobble, the Precession of Equinoxes is a fact, which is simply overruled by Western Astrology. That is why a person, who was Aries at the time of Ptolemy, would still be considered an Aries.

The precession of equinoxes or simply precession, was not known at the time Astrology was established, therefore it disregards the change in the position of constellations as viewed from Earth. But Eastern system by its virtue, since it uses Sidereal system, always follows precessional movement.

Precession of the equinoxes causes changes in apparent position of stars over a cycle of 27,500 years.

From the above image, it is clear that the axis of Earth continues wobbling over a period of almost 25,700 years. During the course, the positions of stars and constellations, as we see them from the Earth, changes.

So the actual, astronomically proven fact is that the Sun is not in the constellation Aries on 23rd March now. It is in Pisces, as shown in the picture below.

The Sun in the Constellation of Pisces on 1 April 2017.

But things differ when you consider the situations under Eastern astrology or Jyotish. The Sidereal Zodiac system used by Eastern Astrologers follows the change in the axis of rotation of Earth. Thousands of years ago, these 2 astrological systems, Western and Eastern completely coincided with each other at the time of their establishment. But as the time passed, the axis of Earth kept wobbling; this made the apparent position of Planets, Constellations, the Sun and the Moon very different from those of the starting point. Since Western system is not allowed to follow the change, it remained fixed. But Jyotish system kept changing over time. Therefore, there is a huge difference between Eastern and Western astrology.

Now we will once again talk about the change.

Over the course of almost 2500 years, the axis of Earth has rotated so much that zodiacs have shifted about 1 month in time. Consider me, a Scorpion under Western system. My date of birth is 18th of November. Under Western astrology, the Sun is in the constellation Scorpio from 23rd October to 22nd November. Under Sidereal system or Eastern astrology, it’s in Scorpio from 13th November to 30th December. But according to real astronomical calculations, the Sun is in the constellation Scorpio from 23rd November to 29th November and my birthday falls in the Libra portion which is from October 30th to November 23rd.

But does that really mean that my sign has changed to Libra? The answer is YES & NO, it’s because this zodiac shift is based on astronomical calculations, which are slightly different from Astrology and aren’t considered by Astrologers. So according to Astrology, my sign is same as before (depending on the system used), but Astronomy, which is 100% scientifically correct and in accordance with modern observations and Mathematics, tells me that my Zodiac has been shifted and I have a new sign.


Astronomers take the scientific route, which is a well established fact with correct data. While Astrologers are still using the old and self-made method of dividing the sky in 12 equal parts of 30 degrees each. This in fact is against the scientific data, which tells us that the dates have been shifted and the Zodiacs are 13 instead of 12.

Astrology was established when there was no extensive knowledge of celestial system. The Geocentric system was in use for explaining the Earth-Sun-Planetary system, which considered Earth to be stationery and everything to revolve around it. There was no knowledge of celestial mechanics at that time. Therefore, astrology is also called a pseudoscience, which does not have any scientific and correct foundation.

Below is the comparison of different zodiac systems.

Comparison Chart

Aries14 April – 14 MayMarch 21 to April 20April 18 to May 13
Taurus14 May – 14 JuneApril 21 to May 20.May 13 to June 21.
Gemini14 June – 14 JulyMay 21 to June 21.June 21 to July 20
Cancer14 July – 14 AugustJune 22 to July 22.July 20 to August 10
Leo14 August – 13 SeptemberJuly 23 to August 22.August 10 to September 16
Virgo13 September – 14 OctoberAugust 23 to September 22.September 16 to October 30
Libra14 October – 13 NovemberSeptember 23 to October 22October 30 to November 23
Scorpio13 November – 14 DecemberOctober 23 to November 22November 23 to November 29
OphiuchusNot ApplicableNot ApplicableNovember 29 to December 17
Sagittarius14 December – 13 JanuaryNovember 23 to December 21December 17 to January 20
Capricorn13 January – 12 FebruaryDecember 22 to January 20January 20 to February 16
Aquarius12 February – 14 MarchJanuary 21 to February 18February 16 to March 11
Pisces14 March – 14 AprilFebruary 19 to March 20March 11 to April 18.


Since both, new zodiac signs and Eastern zodiac signs rely on Sidereal zodiac system; they both tend to change over the time. But even though Sidereal Zodiac system is not completely correct. A minor difference of a few days is because new Astronomical Zodiac system also includes Ophiuchus, the 13th constellation, whereas it is not included in Eastern system. Also, the Sun is said to be in the Constellation Scorpio for 1 month in both Sidereal and Tropical Zodiac systems, but the fact is, it’s there just for 7 days.

I will now touch the case of 13th zodiac, Ophiuchus the Snake Holder. Ophiuchus is a constellation and the Sun on its tour through the constellations, passes through Ophiuchus from November 29th to December 17th. Based on this path of the Sun, the constellation Ophiuchus is also eligible for being a part of zodiacs and in fact it really is. Astronomers always regard it as a zodiac constellation but astrologers have forgotten Ophiuchus because they divide the whole sky of 360 degrees in 12 equal parts of 30 degrees each, therefore there is no room for Ophiuchus in zodiacs, even though it is a part of it. This once again is a demolition of scientific fact. It is in a complete disagreement with what science is telling us now. So we can surely say that Astrology is an “Unscientific Science” having no scientific roots.

The line of Ecliptic passing through the Constellation Ophiuchus.

Constellation Ophiuchus as depicted in Urania’s Mirror, a set of cards published in London in 1825.

You can be sure that the sign which you were told from your birth is not the right one, except for a few people. You can continue to take the unscientific route of Astrology and proclaim yourself the same sign as it was 2500 years ago, or you can choose to accept the truth and welcome your new sign.

This change of zodiacs did not happen overnight. In fact, it took 3 millenniums to reach at this point. In 23,200 years, I will once again become a Scorpion. Until then, I can only wait, and prove to be a good Libra.


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  1. Very well written mate. In detail, and not confusing as well. Nice job. But I would still prefer to be Scorpion, than a Libra 😀

    • Rafia on January 18, 2011 at 11:35 am
    • Reply

    Thank You Bilal- that was informative-

    Note: I am not that welcoming in my nature like Pisces, so let me act Aries please 😉

    1. You’re welcome Rafia baji,

      Note: Keep running as an Aries, even when you have a better option to swim like Pisces 😛

  2. Very comprehensive and interesting!
    Well-explained and knowledgable, now I know what its all about.
    But I love my Libra 😀

    1. Thanks Hafsa. Share it with your friends if you liked it.

      And this Scorpion was not mine at all, I am a Libra by birth 🙁

  3. Doesn’t matter what Zodiac sign I was before (because its all meaningless anyway), this is a well written and informative piece. Good job!

    1. Thanks Ramiz 🙂

    • Rukhama on January 18, 2011 at 9:40 pm
    • Reply

    i like this topic..u ve searched well abt it….keep it up..:)

    • Rukhama on January 18, 2011 at 9:42 pm
    • Reply

    i m TAURIAN…n i m proud to be one…:)
    well nice approach…well done..!!

    • Laura on January 18, 2011 at 11:45 pm
    • Reply

    Thanks for the clarification! Great pics, and your blog looks good too. Astrology is a silly game, but I do have some measure of respect for those who seek meaning in everything because they believe everything is connected. It is a lovely sentiment, as you scientists do concur.

    1. Thank you Ma’am. I guess astrologers can be better if they follow the scientific truth, rather than their own methodology

  4. Very well worked and comprehensive article indeed.
    However, I would point out that Astrology is not the oldest science as it is not science at all. It is what is coined by scientists as pseudoscience as it does not employ scientific methodology of hypothesis and experiments to proof an idea. And Astronomy is as old as Astrology. Even the idea to believe that Earth is the centre of Universe and stars, planets, Moon and Sun revolve around us is also Astronomy as it was based on observation. A hypothesis that is proven to be wrong is also science as it paves the way for a correct hypothesis. Astrology, on the other hand, is not even based on any observation.
    Astrology is to Astronomy is as Magic is to Medicine. And Medicine is itself as old as the human belief of Magic to cure disease. Medicine took baby steps and moved forward in gallops and strides after trial and error and observations throughout human history. Magic is anything but this.

    1. Thank you Sir,

      And thank you for pointing it out, I have made it to “Methodology” above. I dont know why Astrologers are hesitant to act upon this simple scientific fact that zodiacs are 13, not 12. Its a fixed system which can not be changed by them. But if overruled, then it will result in their method being called a pseudoscience.

    • Amjad Nizamani on January 20, 2011 at 5:13 pm
    • Reply

    An Excellent post Bilal. You’ve debunked poor Astrology 🙂
    Well, we need to accept the facts and move on with life. Changing sign doesn’t really mean anything.

    1. Thanks Amjad, the motive behind this article is just to present the readers with all the facts, now it depends upon them whether they accept fact or fake 🙂

    • XuLfI on January 21, 2011 at 12:35 pm
    • Reply

    ssheew!! 😛
    me still CaPrIcOrN 😀

    thanx bilal bro………. 🙂

    1. You’re welcome Xulfi,

    • Fahad Laghari on January 23, 2011 at 2:41 am
    • Reply

    Excellent Bilal.
    This was a great read, it was informative. Zabardast.

    As you have mentioned the errors in the basics of astrology, and I would like to add that there are no statistically significant observations that movement of stars has effect on human affairs.
    It shouldn’t be in newspapers, it should be in the museum as part of the history.

    By the way, this website requires me to answer a security question “what is 13+7?” before clicking on submit comment. How mathematical!

    1. Thank you Fahad bhai.

      Truly, not a single effect of Stars and Planets has been observed on humans or on the events happening. Seems like its time for astrologers to wind up their cards.

      I have looked at my horoscopes many times, but it always tell me such stupid things, which never ever really happen in my life. One horoscope told me that I would be successful in business trip. And at that time, I was 9 or 10 years old.

      And this mathematical question is added to check the maths solving capability of doctors, and those who did F.Sc in pre-medical (like me).

      I will have to answer 4+14=?
      Take care.

    • shadia khatri on January 26, 2011 at 10:36 am
    • Reply

    Kind words are very powerful weapon. We all need to hear them. They create positive emotions not only for other people but for us as well.

    Excellent and informative work Bilal… but Mr ramiz said well that its all meaning less …but u r on the right track. Keep it that way… May your shadow never grow less .. because u r so devoted bilal. With God’s blessing you will succeed in anything.

    1. Thanks for your encouraging comments Ma’am.

      The movement of Sun and Planets through Zodiacs is a scientific fact, and we astronomers regard it just as a natural phenomena. But astrologers regard it as something Super Natural and they think and claim that all this movement causes effects on the lives of people, which is totally wrong and is meaningless.

      Thanks once again. Your positive comments and prayers will help me counter every obstacle in my life.

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