Sun-sign compatibility · water and air · three signs apart
Cancer and Libra compatibility
Cancer and Libra are three signs apart on the wheel, a square of about 90°: water and air, both cardinal. Astrology reads the angle between two Sun signs as the first measure of a pair, and the rest of the two charts as the rest of the story.
This year the Sun is in Cancer from 21 June to 22 July and in Libra from 23 September to 23 October. 3 famous couples in StarMap's dataset are a Cancer and a Libra, where chance would give about 5.9: Zac Efron and Michelle Rodriguez, Shelley Duvall and Paul Simon and Jessica Simpson and John Mayer. Among the 537 couples with both Sun signs certain, that makes this the 73rd most common pairing of the 78. A Sun sign is one placement of ten, and the two whole charts say far more than the two signs.
Each sign has its own page: Cancer and Libra, with its dates to the minute, its traits and the famous people born under it.
What astrology reads for Cancer and Libra
Three signs apart is the square, and astrology reads it as friction with a purpose. The two signs share a modality, so both want to act in the same way, by starting, by holding or by adapting, but from elements that do not mix, and each tends to feel that the other is doing the right thing in the wrong manner. The tradition is plain that this angle is felt: these are the pairs that argue about how.
It is also, in the same tradition, the angle that gets things built. Two Suns at a square give each other something to push against, and astrologers read the pairing as one in which both people grow because neither can settle. What the reading asks is that the friction be aimed at the task rather than at each other; the rest of the two charts, the Moons and Venus especially, says how easily that happens.
Water with air
Air with water is read as the thinker and the feeler: one wants to understand the feeling, the other wants it understood. The tradition reads the pairing as curious and tender when it goes well and as two people talking past each other when it does not, since air names what water would rather be felt. Astrologers read it as the pairing in which listening does most of the work.
Cardinal with cardinal
Both signs are cardinal, the starting signs of their seasons, and the tradition reads two cardinal people as two leaders in one relationship: both want to set the direction, and the question is who goes first on which day. The reading is of a pair that gets a great deal started and has to decide on purpose who finishes.
These are readings of the Sun signs alone, written for reflection and entertainment. They describe tendencies the tradition assigns to an angle, not two people, and they do not say whether a pair lasts.
Cancer in love, Libra in love
Cancer
In love, Cancer commits. It wants a home with someone in it, and it shows love by looking after: the meal, the blanket, the message to check you got back. It is easily hurt and slow to say so. Its lesson is that a partner cannot read the mood it is hiding, however well it reads theirs.
Libra
In love, Libra is made for partnership and knows it. It is attentive, considerate and romantic, and it can lose itself in the other person while trying to keep the peace. Its lesson is that a relationship with two whole people in it is more balanced than one with one person bending.
483 famous people have the Sun in Cancer for certain and 517 in Libra: every Cancer Sun and every Libra Sun, each with a birth chart.
Famous Cancer and Libra couples
Of the 537 spouse and partner pairs in StarMap’s dataset whose Sun signs are both certain, 3 are Cancer and Libra. From the share of each sign among every couple’s members, chance alone would give about 5.9, a ratio of 0.51, which makes this the 73rd most common pairing of the 78. Their sky match, from the angles between the two charts, averages 67 out of 100 against 67 for every couple counted. With about seven couples a cell, a ratio between a half and double is what chance produces; the counts describe the dataset, not the signs.

54Zac Efron and Michelle Rodriguez
Listed as partners in 2014

73Shelley Duvall and Paul Simon
Listed as partners, 1976 to 1978

75Jessica Simpson and John Mayer
Listed as partners, 2006 to 2007
All famous couples, each scored from both birth charts.
Both signs in one chart
The two signs also meet inside one chart, when the Sun is in one and the Moon in the other. Astrologers read a Sun and Moon three signs apart the way they read the two Suns above, as a square between how a person is seen and how they feel.
Sun in Cancer, Moon in Libra: 23 famous people
Sun in Libra, Moon in Cancer: 19 famous people
Only people whose Sun and Moon signs do not depend on an unknown birth time are counted. The Moon in Libra and the Moon in Cancer have pages of their own.
Questions people ask
Are Cancer and Libra compatible?
By Sun sign alone, astrology reads Cancer and Libra as a square, three signs apart: water and air, both cardinal. That is a reading of one placement of ten and not a verdict on two people. In StarMap's dataset of famous couples, 3 are Cancer and Libra, against about 5.9 that chance would give, a ratio of 0.51. The angles between two whole charts, Moon to Moon and Venus to Mars among them, say more than the Sun signs can; the comparison is free on StarMap.
How many famous couples are Cancer and Libra?
3 of the 537 couples in StarMap's dataset with both Sun signs certain, Zac Efron and Michelle Rodriguez, Shelley Duvall and Paul Simon and Jessica Simpson and John Mayer. Chance alone would give about 5.9, which makes it the 73rd most common pairing of the 78. Their sky match, from the angles between the two charts, averages 67 out of 100 against 67 for every couple counted.
Who has the Sun in Cancer and the Moon in Libra?
23 people in StarMap's dataset have the Sun in Cancer and the Moon in Libra, George W. Bush, Ariana Grande and Sylvester Stallone among them. 19 people in StarMap's dataset have the Sun in Libra and the Moon in Cancer, Günter Grass, Graham Greene and Charlton Heston among them. The Moon's sign depends on the day and often on the hour of birth, so only people whose Moon sign is certain are counted.
Sun signs are computed from the Sun’s position with the astronomy-engine ephemeris, checked against Swiss Ephemeris, in the tropical zodiac. Birth data and relationship data come from Wikidata; birth times, where StarMap has one, from Astro-Databank with their Rodden rating. A couple is counted only when the Sun was in one sign for the whole of each birth date. Readings describe what the tradition assigns to an angle, for entertainment and self-reflection; StarMap predicts nothing. Compare two whole charts.
Photo credits (12 photos from Wikimedia Commons)
Each link opens the photo’s page on Wikimedia Commons, which states its author and licence.