Scheat in the birth chart: the red corner of the Great Square

Star data

sefstars catalogue, Swiss Ephemeris 2.10.03.

Scheat is the red star at the north-western corner of the Great Square of Pegasus. In the tropical zodiac it stands at the very end of Pisces, a fraction of a degree from Aries, and within a couple of decades precession will carry it across the boundary. Ptolemy gives the bright stars of the Horse the nature of Mars and Mercury, the same formula as for Betelgeuse.

In the sky

The Great Square is the main landmark of the autumn sky: four stars of similar brightness marking a large, nearly empty square. Three of them belong to Pegasus, the winged horse; the fourth, Alpheratz, is formally part of Andromeda. Scheat is the one at the upper right corner when the Square stands high in the south.

Scheat is a red giant of spectral class M2.5, about 200 light-years away. Its surface is cool, about 3,700 kelvin, but the star is huge: some 95 times the Sun's radius. Placed where the Sun is, it would reach beyond the orbit of Mercury. Much of its light comes out in the infrared, and counting that, it is about 1,500 times as luminous as the Sun. Like many red giants it changes brightness irregularly, by about half a magnitude, enough to notice with the naked eye. It loses gas in a steady wind, and water vapour has been found in the thin envelope that surrounds it.

Scheat lies about 31° north of the ecliptic. A conjunction by zodiac degree is therefore a projection: the planet and the star share a longitude but are far apart in the sky. For stars at this distance some astrologers prefer parans.

Finding it from Ukraine

Pegasus is a constellation of autumn evenings. From September to November the Great Square stands high in the south in the evening, and from Ukraine it is hard to miss. Scheat is the corner star with a distinctly orange-red tint, and the colour shows well in binoculars.

From the latitude of Kyiv Scheat climbs to about 68° above the southern horizon, well over halfway to the zenith. In the zodiac the Sun passes it around the March equinox.

The name

The origin of the name is disputed. Richard Hinckley Allen, in Star Names: Their Lore and Meaning (1899), derives it either from Arabic al-sa'id, "the upper part of the arm", or, following a suggestion by Hyde, from the Arabic word sa'd that appears in the names of the three pairs of stars that follow it. A more recent explanation reads it as Arabic for "the shin", a name that originally described a star in another figure and was moved to Pegasus by mistake. Arabic astronomers themselves called the star Mankib al-Faras, "the shoulder of the Horse", which survives as the alternative name Menkib. Scheat is the official name approved by the International Astronomical Union in 2016.

Pegasus in Greek myth is the winged horse that sprang from the blood of Medusa after Perseus cut off her head. In the story Allen retells, Bellerophon caught him and rode him to kill the Chimaera; later Jupiter, angered by the rider's boldness, sent an insect to sting the horse, which threw Bellerophon off.

Nature according to Ptolemy

In the first book of the Tetrabiblos, among the stars north of the zodiac, Ptolemy describes "the bright stars in the Horse" as being of the nature of Mars and Mercury. Scheat is one of those bright stars.

Mars stands for drive, heat, conflict and a readiness to take risks. Mercury stands for intellect, speech, quickness and restlessness. Together they describe a sharp, active mind with a combative edge: fast to argue, fast to move, not always patient with obstacles. In this formula the two planets are equal partners, unlike Procyon, where Mars is only a minor addition to Mercury. The overview explains how these planetary formulas are read.

After Ptolemy

Scheat is not among Agrippa's fifteen Behenian stars. In the second book (chapter 31) Agrippa does list "the Shoulder of the Horse", of the nature of Jupiter and Mars, and the Horse's Shoulder is Scheat's Arabic name, but the degree he gives does not fit Scheat well, so the identification is uncertain. The clearest later note in Allen concerns water. With Markab, the neighbouring corner of the Square, Scheat formed an Arabic lunar station called al-Fargh al-Muqdim, "the fore spout" of a water bucket, and Allen notes that several old names for the two stars together refer to water. He also records that in astrology Scheat signified "danger to mankind from that element", meaning water.

This is a reputation from the history of the tradition, built on names and images. It is not a forecast, and it says nothing about any particular person born with the star prominent.

Conjunctions with planets and angles

Scheat is used by conjunction, with an orb of about 1° (more on the orb). Because of its distance from the ecliptic many astrologers treat a longitude conjunction with Scheat as weaker than one with a star close to the Sun's path. Two typical cases show how tradition reads it:

• Scheat with Mercury. A star of Mars and Mercury on Mercury gives the planet more speed and a sharper tongue. Astrologers read it as a quick, independent and argumentative mind that enjoys debate and dislikes being told what to think.
• Scheat on the Ascendant. The Ascendant shows manner and first reactions. Here the star's colour appears as restlessness and directness, a readiness to move first and to speak one's mind.

Precession: from Pisces to Aries

Scheat is a fraction of a degree from the end of Pisces. At the usual rate of about 1.4° a century (precession), it will cross into Aries in the mid-2040s. Charts from the twentieth century and from today have it in the last degrees of Pisces; charts from after the crossing will show it at the start of Aries.

There is a neat side effect. The beginning of Aries is the point the Sun reaches at the March equinox, so for a while after the crossing the Sun will meet Scheat almost exactly on the equinox. The change of sign does not alter the star's nature: the nature comes from Ptolemy's formula, not from the sign.

In celebrity charts

Conjunctions within 1° to the planets from the Sun to Saturn and to the chart angles.

• Hillary Clinton: Moon, orb 0°06′
• Kim Kardashian: IC, orb 0°38′
• Antoine Griezmann: Sun, orb 0°41′

Find fixed stars in your chart