Every few years a headline goes viral saying the zodiac has changed, there is a 13th sign called Ophiuchus, and you might not be the sign you thought you were. The short answer: your astrology sign has not changed.

The "new zodiac sign dates" describe when the Sun passes in front of the actual star constellations. Western astrology does not use the constellations to set the signs. It uses the seasons. Here is the whole story in plain words.

Where the "new zodiac signs" story came from

In 2016, a NASA education page for kids explained how the sky has shifted since ancient times. It mentioned that the Babylonians, about 3,000 years ago, split the sky into twelve parts and left out a thirteenth constellation, Ophiuchus.

The internet ran with it. Headlines claimed NASA had changed the zodiac. NASA later had to clarify that it had not changed anything. It had only done the math on where the constellations sit today.

The same story resurfaces every year or two, usually with the same list of "new dates."

The "new" zodiac sign dates, with Ophiuchus

This is the list that goes around. It shows roughly when the Sun appears in front of each constellation today. The exact dates move by a day or so depending on the year and source.

  • Capricorn: about Jan 20 to Feb 16.
  • Aquarius: about Feb 16 to Mar 11.
  • Pisces: about Mar 11 to Apr 18.
  • Aries: about Apr 18 to May 13.
  • Taurus: about May 13 to Jun 21.
  • Gemini: about Jun 21 to Jul 20.
  • Cancer: about Jul 20 to Aug 10.
  • Leo: about Aug 10 to Sep 16.
  • Virgo: about Sep 16 to Oct 30.
  • Libra: about Oct 30 to Nov 23.
  • Scorpio: about Nov 23 to Nov 29.
  • Ophiuchus: about Nov 29 to Dec 17.
  • Sagittarius: about Dec 17 to Jan 20.

Notice how uneven they are. The Sun spends only about a week in front of Scorpio, but more than six weeks in front of Virgo. Constellations are different sizes, so their dates are too.

Why your astrology sign stays the same

Western astrology uses the tropical zodiac. It does not follow the constellations at all. It starts the zodiac at the spring equinox, the moment around March 20 when day and night are equal and spring begins in the Northern Hemisphere. From there it divides the year into twelve equal 30-degree slices.

That means:

  • Aries always begins at the spring equinox.
  • Cancer always begins at the June solstice.
  • Libra always begins at the September equinox.
  • Capricorn always begins at the December solstice.

The signs are tied to the seasons, not to stars. When astronomers say the constellations have drifted, they are right. It just does not change the tropical zodiac, because the tropical zodiac never followed the constellations in the first place.

So the familiar dates still hold: Aries from about Mar 21, Taurus from about Apr 20, and so on through Pisces, which ends around Mar 20.

Why the stars have shifted

The drift is real, and it has a name: the precession of the equinoxes. Earth wobbles slowly on its axis, like a spinning top. Over about 26,000 years, that wobble shifts where the equinoxes fall against the background stars, by about one degree every 72 years.

When the zodiac was first laid out, the spring equinox lined up with the constellation Aries. Today it sits in front of Pisces, and it is slowly heading toward Aquarius. That is where the phrase "the Age of Aquarius" comes from.

Some astrology traditions do follow the stars. Vedic (Indian) astrology uses the sidereal zodiac, which is adjusted for precession. In that system many people's Sun sign is one sign earlier than in Western astrology. That is a real difference between two traditions, and it is not a "change" either.

What about Ophiuchus, the 13th sign?

Ophiuchus is a large constellation, often drawn as a figure holding a serpent. The Sun does pass in front of it every year, from about late November to mid-December.

Most astrologers do not treat it as a zodiac sign, because the tropical zodiac is built on twelve equal parts of the year, not on constellations. A small number of astrologers do use a 13-sign system, and some people born in early December enjoy reading about the traits linked with Ophiuchus: healing, curiosity and a search for hidden knowledge. It is a fun idea to explore. It is just not part of mainstream Western astrology.

How to know your sign for sure

Your Sun sign comes from your birth date in the tropical zodiac. If your birthday is near the edge of two signs, the year and even the time of day can matter, because the Sun changes sign at a slightly different moment each year.

The easiest way to be certain is a free birth chart. It uses your exact date, time and place, and shows your Sun, Moon and rising signs together. You can also look up any sign directly, such as the Sagittarius page or the Scorpio page, the two signs most often "moved" in these headlines.

FAQ

Did NASA change the zodiac signs?

No. A 2016 NASA education page explained that the constellations have shifted over thousands of years. NASA did not change astrology, and the signs used in Western horoscopes stayed the same.

What are the new zodiac sign dates?

The "new" dates describe when the Sun passes in front of each star constellation today, including Ophiuchus from about Nov 29 to Dec 17. Western astrology does not use these dates, because it follows the seasons rather than the constellations.

Am I an Ophiuchus?

If you were born between about Nov 29 and Dec 17, the Sun was in front of the Ophiuchus constellation. In Western astrology you are still a Sagittarius.

Why are there 12 zodiac signs and not 13?

The tropical zodiac divides the year into twelve equal parts starting at the spring equinox. Twelve also matches the roughly twelve lunar cycles in a year, which is one reason ancient astrologers chose it.

Is my zodiac sign different in Vedic astrology?

Often, yes. Vedic astrology uses the sidereal zodiac, which is about 24 degrees behind the tropical one. Many people's Vedic Sun sign is the sign before their Western Sun sign.