13 Signs Zodiac and Ophiuchus Astrology

The 13 Signs zodiac follows the constellations that cross the ecliptic. Its signs are unequal, and it has a thirteenth sign, Ophiuchus, between Scorpius and Sagittarius. In AstroApp you can calculate every chart type, table, forecast and report in the 13 Signs zodiac, and you can show it next to the tropical zodiac on the same wheel to read both at once. The 13 Signs module is included in the Pro edition and in Financial Gold.

Sign Boundaries

There are many variations of how the 13-sign Zodiac can be calculated, so AstroApp provides multiple methods of defining the 13 Signs Zodiac boundaries:

• Walter Berg
• Vasilis Kanatas
• Athen Chimenti
• the IAU constellation borders
• Pedro de Damborenea
• multiple midpoint combinations of those, such as Berg/Chimenti

Whatever variation you choose, the planet details table lists the position of every object in the 13 Signs zodiac. A second table shows where each of the 13 signs begins and ends in the 12-sign zodiac, with its ascensional times, which also vary from sign to sign because the signs are unequal.

The IAU constellations table maps out where each planet and point in your chart actually sits, using the official 88-constellation borders established by the International Astronomical Union in 1930. You'll see these listed right alongside their 13-sign placements.

Because some celestial bodies stray far from the ecliptic path, the two don't always match up. For instance, the Moon might drift into Cetus or Auriga, while Pluto and asteroids often pop up outside the traditional zodiac. You can also view a separate table tracking the exact dates planets cross these constellation boundaries, or enable "True IAU boundaries" to draw any 13-sign chart using the exact constellation borders for your date.

13-House Systems

Several astrologers have proposed a division into 13 houses to go with the 13 signs. Four 13-house systems are supported, and you can use each of them with any chart type:

• Bergian 13 houses
• the Raw Goddess variation
• the Bergian-Lovelace variation
• 13 equal houses

You can count reversed houses from the Ascendant or from the IC. The house cusps table and the planet details table show positions in the 13 houses, and a graph shows how the planets are distributed through them.

Chart Styles

You can choose from seven chart styles designed for the 13 Signs zodiac, and make any of them your default:

• 13 Signs wheel
• dual-zodiac wheel, with the 13 signs and the 12 signs on one chart
• 13 Signs anchored, and 13 Signs anchored on tropical Aries
• 13 signs with 13 houses, in several variations
• 13 Signs rainbow, with the rainbow effect on the houses as well
• multi-zodiac wheels: tropical, sidereal, galactic and 13 Signs in rings
• multiwheels of up to five charts

The rainbow styles come in regular and Andalusia fonts, and you can use any of AstroApp's chart backgrounds and color schemes with a 13 Signs chart.

Forecasting in 13 Signs

These forecasting tools work in the 13 Signs zodiac:

• transits, as bi-wheels, transit lists and transit searches with results shown in 13 Signs notation
• linear transits across 13 Signs Zodiac
• ingresses, using 13 Signs coordinates
• the lunar phases listing
• transit and progression animation through the 13 signs
• 13 Signs ephemeris generator

Vasilis Kanatas's approach reads solar activity together with the chart, so the module also includes the sunspot tables and graphs, both observed and predicted.

Reports and Chart Search

Three interpretation reports are written for the 13 Signs Zodiac. Kim Lovelace's 13 Signs report, in English, covers the planets in signs and houses. Pedro de Damborenea's report, available in both English and Spanish, covers the planets and planetoids in the 13 signs and 13 houses. Eric Seligson's report covers planets placement within 13 Signs Zodiac boundaries. The interpretation editor supports the 13 Signs zodiac with either 12 or 13 houses, so you can create and sell your own interpretation reports.

You can also search your chart database by 13-sign and 13-house placements. For example, you can specify search criteria to find every saved chart with the Sun in Ophiuchus or Mars in the thirteenth house.

Galactic and Unequal Zodiacs

The 13 Signs zodiac is just one of several unequal zodiacs, and eight of them are supported: 13 Signs, Argo, Stern, Wachsmuth, Vreede, Tucker, Synoptical and Sastri's Vedic division. You can convert planets position data from one to another, and the main tables show the placements of planets and objects in the zodiac you choose.

The galactic zodiac is also supported, with three methods for the Galactic Center calculation, a galactic ephemeris generator, and multi-zodiac wheels that show the tropical, sidereal and galactic zodiacs as rings around one chart.

You can also use the 14 Signs zodiac, which includes the constellation of Cetus, the Whale, between Aries and Taurus, and Ophiuchus between Scorpio and Sagittarius. The 14 Signs chart shows Cetus with its own glyph, and shows coordinates of every planet within the 14 Signs Zodiac boundaries.

Frequently Asked Questions

Which 13-sign boundaries can I use?

You can choose from five: Walter Berg's, Vasilis Kanatas's, Athen Chimenti's, the IAU constellation borders, or Pedro de Damborenea's, plus three midpoint combinations of them. You can switch at any time and recalculate the chart to compare.

Can I see the constellation a planet is actually in?

Yes. The IAU constellations table uses the official borders of all 88 constellations, so it shows the locations/coordinates of the objects within the true constellations (even when they're outside of the ecliptic boundaries), next to its 13 Signs placement.

Can I use the 14 Signs zodiac with Cetus?

Yes. The 14 Signs Zodiac variation is also supported: 14 signs, with Cetus between Aries and Taurus and Ophiuchus between Scorpio and Sagittarius.

Can I see the 13 Signs and the tropical zodiac on one chart?

Yes. The dual-zodiac wheel shows both zodiacs as rings around one chart, and the multi-zodiac styles add the sidereal and galactic zodiacs as further rings.

Can I use the 13-house systems with any chart?

Yes. You can use the four 13-house systems with natal, horary, return, progressed and every other chart type.

Are there interpretation reports for the 13 Signs zodiac?

Yes, three: Kim Lovelace's 13 Signs report, Eric Seligson's report, and Pedro de Damborenea's report on the planets and planetoids in the 13 signs and 13 houses, in English and Spanish. You can also write your own reports using the Interpretations Editor.

Which edition includes 13 Signs astrology?

The Pro edition and Financial Gold both include it.

Can I use transits and progressions in the 13 Signs zodiac?

Yes. You can calculate transits, transit searches, ingresses, lunar phases and 13 signs ephemeris. Additionally, you can animate transits, progressions and returns through the 13 Signs Zodiac.

See Also

• Duodecimal zodiac and 13 Signs astrology, an article by Pedro de Damborenea (in Spanish)
• Pedro de Damborenea and Kim Lovelace, the authors of the 13 Signs reports
• Chart Wheel Styles and Forecasting Tools

Compare editions and prices.