# Ophiuchus, the 13th Zodiac Sign: What It Really Is

> Ophiuchus is a real constellation the Sun crosses each year from late November to mid-December. Why astrology still counts 12 signs, and what NASA said.

- Page: https://novaoracles.com/blog/ophiuchus-13th-zodiac-sign
- Language: en
- Published: 2026-11-06
- Updated: 2026-11-06

Ophiuchus, the Serpent Bearer, is a large constellation that the Sun passes in front of for about 18 days a year, roughly from November 30 to December 17. That is why it is often called the 13th zodiac sign. Western astrology still counts 12 signs, because its signs are equal 30-degree slices tied to the seasons, so a December birthday remains Sagittarius. You can check where any date falls with the [zodiac sign dates tool](https://novaoracles.com/tools/zodiac-sign-dates).

## What is Ophiuchus?

Ophiuchus is one of the 88 constellations astronomers recognize today. Its name is Greek for "serpent bearer", and it shows a man holding a great snake, which forms a separate constellation, Serpens, split into a head on one side and a tail on the other. The Greek astronomer Ptolemy listed it among his 48 constellations in the 2nd century, so the figure itself is ancient.

Myth links the figure to Asclepius, the healer, son of Apollo. He is said to have learned the secret of healing by watching one snake bring herbs to another, and to have grown so skilled that he could bring the dead back to life. Zeus struck him down with a thunderbolt for upsetting the order of the world, then set his image among the stars. The rod of Asclepius, a staff with one snake wound around it, is still a symbol of medicine.

The constellation has some well-known residents. Its brightest star, Rasalhague, takes its name from an Arabic phrase for "head of the serpent charmer". Barnard's Star, one of the closest stars to the Sun, lies inside its borders. In October 1604 a new star flared up near the Serpent Bearer's foot, and Johannes Kepler studied it so closely that it is now known as Kepler's Supernova.

## Why does the Sun pass through Ophiuchus?

The Sun passes through Ophiuchus because the constellation's lower legs reach down across the ecliptic, the line the Sun seems to follow against the stars over a year. In 1930 the International Astronomical Union published official borders for all 88 constellations, drawn by the Belgian astronomer Eugène Delporte. Those borders are straight lines on a map of the sky, chosen so that every star belongs to exactly one constellation. With them in place, 13 constellations touch the Sun's path, and Ophiuchus is one of them.

The borders were never meant to divide the year. They are uneven: the Sun spends about 45 days in Virgo and only about 7 in Scorpius. Here is the stretch of sky the Sun crosses at the end of the year, set beside the astrological signs for the same dates.

| Constellation (astronomy) | Sun's dates | Days | Sign (Western astrology) |
| --- | --- | --- | --- |
| Libra | October 31 - November 22 | about 23 | Scorpio until November 21 |
| Scorpius | November 23 - November 29 | about 7 | Sagittarius from November 22 |
| Ophiuchus | November 30 - December 17 | about 18 | Sagittarius |
| Sagittarius | December 18 - January 18 | about 32 | Sagittarius until December 21, then Capricorn |

The dates follow the IAU borders and can move by a day from year to year. Different sources round them to November 29 or 30 for the start and December 17 or 18 for the end.

## Why does Western astrology keep 12 signs?

Western astrology keeps 12 signs because its zodiac measures the seasons, and the constellations only lent it their names. The signs are called tropical: Aries starts at the spring equinox, Cancer at the summer solstice, Libra at the autumn equinox, Capricorn at the winter solstice. Each sign is exactly 30 degrees, a twelfth of the circle, whatever star pattern lies behind it.

The equal division is Babylonian too. Their astronomers were working with 12 sectors of 30 degrees along the Sun's path by roughly 400 BCE, a count that sits well with the roughly 12 lunar months in a year. Ophiuchus was in the sky then too. It was simply never one of the 12 sectors. When the 1930 borders came along, they described constellations, and the signs stayed the calendar they had always been.

Precession adds to the confusion. The Earth's axis traces a slow circle, like a spinning top, once in about 26,000 years, and the equinox point creeps backward along the ecliptic as it does. Over two thousand years the signs and the constellations of the same name have slid almost a full slice apart. Western astrology follows the equinox and stays with the seasons. The post on [zodiac symbols](https://novaoracles.com/blog/zodiac-symbols) traces how the 12 sign images came to be in the first place.

## What does sidereal astrology say about Ophiuchus?

Sidereal astrology, which includes the Vedic tradition of India, follows the stars instead of the seasons. It still uses 12 equal signs of 30 degrees. It only moves their starting point by the ayanamsa, today about 24 degrees, so that the signs line up again with the fixed stars. Ophiuchus does not appear in that system either.

The two zodiacs are two conventions for the same sky, and the [Vedic astrology chart](https://novaoracles.com/blog/vedic-astrology-chart) post explains the difference step by step. If you are curious, the [sidereal chart](https://novaoracles.com/tools/sidereal-chart) shows your planets in that count. For someone born around December 10, for instance, the tropical Sun sits in Sagittarius and the sidereal Sun near the end of Scorpio. That is a different way of measuring. The [accuracy page](https://novaoracles.com/accuracy) shows how the site checks its sidereal figures against an independent ephemeris.

The idea of a 13-sign zodiac is fairly recent. In 1970 the American writer Steven Schmidt proposed 14 signs, adding Ophiuchus and Cetus. In 1995 the British astrologer Walter Berg published a 13-sign version with Ophiuchus, which became popular for a while, especially in Japan. Neither became standard in tropical or sidereal practice.

## What did NASA say about the 13th zodiac sign in 2016?

In 2016 NASA's Space Place, a website for children, published a short piece on the difference between astronomy and astrology. It explained that the Babylonians saw 13 constellations along the Sun's path, chose 12 to match their 12-month calendar, and left Ophiuchus out. Months later, in September, several news and lifestyle sites ran headlines claiming that NASA had changed the zodiac.

NASA replied on its Tumblr blog that it had not changed any zodiac signs and had simply done the math. Astronomers have known about the Sun's passage through Ophiuchus for centuries, and British media had run a similar story back in 1995. The episode returns every few years, often with the same alarming headline. Nothing about your birth sky changed in 2016, and nothing changes when the story comes back.

## Am I an Ophiuchus?

If your birthday falls between about November 30 and December 17, the Sun stood in front of the constellation Ophiuchus when you were born. That is an astronomical fact about your birthday sky. In Western astrology your sign is Sagittarius, the archer, because the sign covers about November 22 to December 21. You can find more on the [December zodiac signs](https://novaoracles.com/blog/december-zodiac-sign) page, and if your birthday is in late November, the [November zodiac signs](https://novaoracles.com/blog/november-zodiac-sign) page covers the switch from Scorpio to Sagittarius.

Some people like to add the Serpent Bearer to their story, and the myth gives plenty to work with: healing, learning, knowledge passed on with care. You can read it as a personal symbol alongside your sign. Your profile in the [Sagittarius](https://novaoracles.com/blog/sagittarius-zodiac-sign) guide still applies, and so does your [Scorpio](https://novaoracles.com/blog/scorpio-zodiac-sign) neighbor's for a birthday in late November.

## What are Ophiuchus personality traits?

The Ophiuchus traits you find online come mostly from the 13-sign books of the 1990s and from the myth itself. They tend to describe someone drawn to healing, curious, keen to learn and to pass knowledge on, with strong intuition, all lines taken straight from the story of Asclepius. There is no long interpretive tradition behind them of the kind that has built up around Aries or Libra over centuries. Sign readings rest on each sign's place in the seasons, its element and its modality, and Ophiuchus has no place in that pattern, so the traits linked to it are best taken as a retelling of the myth. Taken that way, the Serpent Bearer can still be a good mirror for thinking about what you value.

## Is there an Ophiuchus symbol?

Yes, though it belongs to the constellation. Unicode has a character for it, ⛎ (U+26CE), which arrived with the Japanese carrier emoji, and books on the 13-sign zodiac draw a snake or a wavy line held by a figure. It has no fixed glyph in the classical tradition the way ♐ marks Sagittarius, and you will not find it on a standard birth chart wheel.

## What the 13th sign story shows

The Ophiuchus story is a useful reminder of what a sign is. A constellation is a pattern of stars with borders drawn in 1930. A sign is a 30-degree slice of the year, counted from the equinox, a tradition built for reflection on the seasons and on the time you were born. Both are real, and they answer different questions. To see where the Sun and every planet stood when you were born, in the 12 signs the tradition uses, open the [birth chart](https://novaoracles.com/tools/birth-chart). The [zodiac fundamentals guide](https://novaoracles.com/guides/zodiac-fundamentals) explains how the signs work.

## FAQ

### Am I an Ophiuchus?

If you were born between about November 30 and December 17, the Sun stood in front of the constellation Ophiuchus on your birthday. In Western astrology your sign is still Sagittarius, because the signs are 12 equal slices tied to the seasons. Ophiuchus is part of the sky you were born under, and you can read it as a piece of your birthday's story.

### Did NASA add a 13th zodiac sign?

No. In 2016 NASA's Space Place, a site for children, wrote that the Babylonians saw 13 constellations along the Sun's path and picked 12 for their calendar. News sites turned that into a claim that NASA had changed the signs. NASA replied that it had not changed any zodiac signs and had only done the math, which astronomers have known for centuries.

### What are the Ophiuchus dates?

With the official constellation boundaries the Sun crosses Ophiuchus from about November 29 or 30 to about December 17 or 18, roughly 18 days. The exact day shifts by one from year to year. In Western astrology those dates fall inside Sagittarius, which runs from about November 22 to December 21.

### Is Ophiuchus used in sidereal or Vedic astrology?

No. Sidereal astrology, including the Vedic tradition, also uses 12 equal signs of 30 degrees. It anchors them to the fixed stars instead of the equinox, which shifts every sign by about 24 degrees, yet it keeps the same 12. The 13-sign zodiac is a 20th-century proposal that few astrologers in either tradition follow.