Canopus, the star called Suhayl

The star behind the name

Canopus is the second-brightest star in the night sky, outshone only by Sirius. To the Arabs it was Suhayl, and few stars carried more meaning in the Arabian world: it marked the south, it told the seasons, and poets and storytellers made it a lover, an exile and a brother. Canopy takes its name from it. The name is drawn from Canopus, the star that served as a seasonal clock and navigational compass, and a nod to the romantic, tragic Arab folklore around it; it also carries the older sense of a canopy of heaven, the night sky as a sheltering dome.

Canopus never climbs high for anyone in the northern lands where Arabic astronomy flourished. From most of Arabia it stays low over the southern horizon, often golden through the thick air near the ground, and from most of Europe it never rises at all. That low, southern, seasonal star is the one this page follows, through the stories told about it, the calendar it kept, the travelers it guided, and the place it holds in a chart.

Suhayl in Arabic star lore

The Arabs told several stories about Suhayl, and they do not all agree. In one, recorded in Edward Lane's Arabic–English Lexicon, Suhayl had been a harsh collector of tithes on the road to Yemen, and was turned into a star for it. In another, Sirius and Procyon are his two sisters, ukhtā Suhayl. When Suhayl went down into the south, Sirius followed him across the Milky Way and so was named al-ʿAbūr, the one who crossed; Procyon stayed behind and wept until her eyes grew bleary, and so is al-Ghumayṣāʾ. A further telling makes Suhayl the suitor of al-Jawzāʾ, the figure of Orion, a match that ended badly and sent him fleeing south.

She is of the north when she rises, and Suhayl, when he rises, is of Yemen.

The most famous lines about the star are about a marriage. The poet ʿUmar ibn Abī Rabīʿa, hearing that a woman named al-Thurayyā, the Arabic name of the Pleiades, was to marry a man named Suhayl, asked how the two could ever meet: she is of the north when she rises, and Suhayl, when he rises, is of Yemen. The joke works because every listener knew the sky. The Pleiades rise in the north-east and climb almost overhead; Suhayl rises in the south-south-east and never leaves the horizon.

The star travelled east as well. In Persian it is Soheil, and because it barely rises over much of Iran, "becoming Soheil" came to mean someone who is rarely seen. Ferdowsi likened a beloved's beauty to "the Canopus of Yemen", and the fifteenth-century Persian retelling of the animal fables of Kalīla wa-Dimna was titled Anvār-i Suhaylī, the Lights of Canopus, a pun on the name of its patron, Aḥmad Suhaylī. Lexicographers of Arabic distinguished this star, Suhayl al-Yaman, Suhayl of Yemen, from a fainter Suhayl al-Shām.

A seasonal clock

Before printed calendars, the desert kept time by the stars that rose just before dawn, and Suhayl's dawn rising was one of the great markers of the year. Lane's lexicon records that around the time of the Hijra, in the seventh century, it rose before dawn in central Arabia about 4 August (Julian calendar), when the fruits ripened and the qayẓ, the season of greatest heat, came to an end. The saying went that once Suhayl was seen the nights would cool, even if the daytime heat lingered for weeks.

The custom is still alive in the Gulf. In the UAE, the Emirates Astronomy Society dates Suhail's rising to about 24 August, with the first clear sightings usually two to four days later, and the newspapers greet it every year as the turn of the season. Emirati tradition counted a whole year from that morning, the Suhaili year, divided into seasons that once set the rhythm of fishing, pearling and farming. Meteorologists add a sensible note: the star does not cool the air, it simply rises at the time of year when the Sun is lower, the days are shorter, and the nights begin to ease.

Canopy keeps time in a related old way, by the Moon's twenty-eight stations, the lunar mansions, whose stars' dawn risings and settings made up the Arabs' anwāʾ calendar.

A navigator's star

Canopus has always belonged to travelers. Its Greek name, Kanōbos, is usually traced to Canopus, the pilot of Menelaus's ship, and on the old star maps it marked the steering oar of Argo, the ship of the Argonauts. The Bedouin of the Sinai and the Negev took Suhayl and the Pole Star as their two chief guides by night: the Pole Star fixed in the north, Suhayl rising and setting in the south.

It guided the measurers of the world too. The Greek scholar Posidonius used the different heights of Canopus above the horizon at Rhodes and at Alexandria to estimate the size of the Earth, and in 1153 the philosopher Ibn Rushd, Averroes, saw the star at Marrakesh, though it was invisible from his native Córdoba, and used the difference to argue that the Earth is round. Eight centuries later Canopus was still steering: in 1964 the Mars probe Mariner 4 locked onto it to hold its orientation, the first time a spacecraft had used a star this way, and many spacecraft since have carried what engineers still call a Canopus star tracker.

Canopus in astrology

Astrology reads a fixed star chiefly by conjunction: a planet or angle standing on or near its degree takes on something of its nature. Ptolemy's Tetrabiblos likens the bright stars of Argo to Saturn and Jupiter, and Canopy gives Canopus that double nature, counting it among the fortunate stars. By tropical longitude it stands near 15°19′ of Cancer (2025 position), moving forward about a degree every seventy-two years; Sirius stands near 14°24′ of Cancer, so the two brightest stars in the sky, the brother and the sister who crossed the river of the Milky Way, fall within a degree of each other in the zodiac.

In Canopy, Canopus is one of thirty-five fixed stars set against your birth chart. When it lies within three degrees of a planet, the Ascendant or the Midheaven, the reading, drawn from the classical sources, speaks of wide travel and distinction in distant lands, of fame and high position, and of wisdom and ceremonial ability. It is not one of the fifteen Behenian stars of the talisman-makers, which you can read about on the fixed stars page, but it is one of the brightest and most storied of the thirty-five.

How to see Canopus

Canopus lies about fifty-three degrees south of the celestial equator, so it never rises for anyone north of about 37° latitude, roughly the latitude of San Francisco, Seville and Athens. South of that line it can be found low over the southern horizon: from the Gulf before dawn from late August, and in the evening from about January to March; from Florida, Texas or the Gulf Coast best on late-January and February evenings. In the Southern Hemisphere it rides high, and south of about 37° south it never sets. When Sirius stands due south, Canopus lies almost directly beneath it, close to the horizon, where it often flickers yellow and gold. It lies about 310 light-years away, a giant star more than ten thousand times as luminous as the Sun.

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