Finally, someone who can keep up?

Are Aries and Sagittarius compatible?

Aries and Sagittarius are a trine: both fire signs, one cardinal and one mutable, four signs apart on the zodiac wheel. Astrologers have called the trine the most harmonious angle since Ptolemy. That's the Sun alone. The rest of the story is in the whole chart: Venus, Mars, the Moon and the descendant.

You're here because of someone.

The Sun signs say easy. Two whole charts say far more.

Your card is worked out from the day, the minute and the place you were born, not from a sign you share with a twelfth of the planet.

Every Aries and every Sagittarius reads this page. Only your card knows you.

Find out your true compatibility.

Print my card$9.95 + tax Gift them a ticketand find out theirs

Admit one Aries Fire · Cardinal Mar 21 – Apr 19

Admit one Sagittarius Fire · Mutable Nov 22 – Dec 21

△︎ Trine · 120°Fire + fire · cardinal + mutableHarmonious, in Ptolemy’s terms

What it is: synastry, the art of comparing two charts

Comparing two people's charts has a name: synastry. Astrologers lay one chart over the other and look at the angles between the two sets of planets, the same angles the old books use inside a single chart.

Sun-sign compatibility is the shortcut version. It compares only the two Suns, and the angle between them is the aspect: four signs apart is a trine, two apart a sextile, three apart a square, six apart an opposition. Ptolemy called the trine and the sextile harmonious, and the square and the opposition disharmonious. ¹

Elements describe temperament (fire, earth, air, water) and modes describe pace (cardinal starts, fixed holds, mutable adapts). A pair can share one, both or neither. Aries and Sagittarius share the element but not the mode.

Full synastry goes much further: whose Venus lands on whose Moon, where one person's planets fall in the other's houses, how the two descendants line up. Ptolemy himself compared the Sun and the Moon of both charts, not just the Suns. That is why the same Aries can get on beautifully with one Sagittarius and not at all with another. ²

Why do Aries and Sagittarius click?

The traditional portrait: the same for every Aries and every Sagittarius.

Aries in love

Aries, the old books say, falls first and fast. The pursuit is most of the thrill: the bold message, the surprise trip, the argument that turns into a kiss. Traditionally an Aries in love is loyal, direct and impatient with games, and wants a partner who'll push back. Bore a Ram, the story goes, and it's out of the door before you've noticed.

Sagittarius in love

Sagittarius loves the way it travels, in the old portrait: wide open, a little reckless, always up for one more adventure. Traditionally an Archer wants a partner who's also a co-pilot, and freedom inside the relationship, not outside it. Honest to a fault, the books say. Fence one in and it starts looking at the horizon.

Together

Fire with fire. Tradition hands you the same temperament twice: both want to go first, both talk louder when the other one does. Bonfire, or two matches racing each other to the end?

Cardinal meets mutable. One sets the course and the other adjusts it on the way, which is either teamwork or a lot of U-turns.

Fire meets fire again, this time with a passport. Aries brings the head-first start and Sagittarius brings the long horizon, and the picture tradition paints is two people booking a trip on a Tuesday night for Friday morning. Who remembers to water the plants is anyone's guess.

Where it comes from: comparing charts, from Babylon to your phone

Era by era, with sources. More in the Reading Room.

Ancientc. 450 BCEThe Babylonian zodiac settles into twelve equal zones, the frame later comparisons of signs are built on. ³
Ancient410 BCEThe earliest known horoscopes, from Babylon and Nippur, date to this year. ³
Classical2nd century CEPtolemy's Tetrabiblos names the aspects between signs and calls the trine and sextile harmonious, the square and opposition disharmonious. ^4,1
Classical2nd century CEPtolemy's chapter on the planets' houses puts Aries under Mars and Sagittarius under Jupiter. ¹
Classical2nd century CEAries and Sagittarius sit in the same one of Ptolemy's four triangles, the fire one, which he puts under the Sun by day and Jupiter by night. ¹
Classical2nd century CEIn his chapter on marriage, Ptolemy compares two charts: the Sun and Moon of one against the Sun and Moon of the other, reading trines and sextiles between them as concord and squares and oppositions as friction. ²
Classical2nd century CEHis chapter on friends and enemies does the same with the Sun, the Moon, the rising degree and the Lot of Fortune of both people. ²
Medieval12th centuryAbu Ma'shar's introduction to astrology circulates in Latin; the University of Edinburgh holds a 12th-century copy. ⁵
1800s1890Alan Leo's Astrologer's Magazine offers its annual subscribers a free horoscope by post. ⁶
1930s1937R. H. Naylor's newspaper horoscope, begun in 1930, is organised by the twelve sun signs. ⁷
1970s1978Linda Goodman's Love Signs is published by Harper & Row. ⁸
1980s–90s1980–1999Chart services run by computer arrive: Astrodienst in Zürich sells birth charts from 1980 and goes online in 1996. ⁹
Today202430% of US adults consult astrology, tarot or a fortune teller at least yearly, mostly for fun, according to Pew Research Center. ¹⁰

Worked out, not guessed

Aries is sign 1 of 12 and Sagittarius is sign 9: four signs apart, 120°. Trines always share the same element and the same polarity, but not the same mode. Of the 78 possible sun-sign pairings, 12 are trines.
Venus never gets more than about 47° from the Sun, so an Aries's Venus is in one of five signs (Aquarius, Pisces, Aries, Taurus or Gemini) and a Sagittarius's in one of five (Libra, Scorpio, Sagittarius, Capricorn or Aquarius). Which one is a matter of the year and the day.

So who’s going to suggest staying home?

The Sun can’t answer that. These four can, and your card reads every one of them.

Venus · how you love

How do you love, and how do they want to be loved?

That's Venus. It never strays far from the Sun, so an Aries's Venus can only sit in Aquarius, Pisces, Aries, Taurus or Gemini, and a Sagittarius's Venus can only sit in Libra, Scorpio, Sagittarius, Capricorn or Aquarius. Two people with the same sun sign can want completely different evenings.

Your card reads your Venus.
Mars · what you want

Why does every plan turn into a bigger plan?

That's Mars: desire, temper, the way you chase what you're after. It can sit in any of the twelve signs, so two Sagittarius born a season apart can want, and fight about, completely different things.

Your card reads your Mars.
The Moon · what you need

Why do they feel like home one day and a stranger the next?

That's the Moon: what you need when the door's shut and the day's gone wrong. It changes sign every two and a half days. If their Moon falls in your sign… well.

Your card reads your Moon.
The descendant · who you’re drawn to

Why do you keep falling for the same type?

That's your descendant, the edge of the seventh house: the sign setting in the west at your birth minute. Tradition reads it as the partner you keep noticing. It needs your birth time and place.

Your card reads your rising sign and your descendant.