Pegasus: The Winged Horse

Pegasus is upside down in the sky, flying with his belly toward the ground and no clear head to speak of, which is a strange way to draw a horse. What he does give you is a shape nothing else in the sky offers: a near-perfect square of four stars, wide open and empty in the middle, that anchors the whole autumn evening.

Born from a monster's blood

Pegasus was born from the blood of the Gorgon Medusa the moment Perseus beheaded her — a strange, sudden birth for a myth to hand a hero. The rider who eventually tamed him was Bellerophon, who bridled the horse and flew him into battle against the Chimera, a fire-breathing monster, and won. Bellerophon's story does not end well: when he tried to ride Pegasus up to Olympus itself, he was thrown from the horse's back. Pegasus, unlike his rider, kept flying, and eventually into the stars.

The empty box that isn't actually empty

The Great Square of Pegasus is formed by four stars, three of which belong to Pegasus and one of which is technically Andromeda's Alpheratz, shared between the two figures at their corner. Within Pegasus itself, Markab (Alpha Pegasi, magnitude 2.48) and Scheat (Beta Pegasi, magnitude 2.42) mark two corners of that square. Scheat is a red giant and a known variable, so its brightness shifts slightly over time. Enif, Epsilon Pegasi at magnitude 2.4, marks the horse's muzzle out ahead of the square — the brightest of the constellation's named stars, an orange supergiant.

The square itself looks empty to the naked eye, which is the point of using it as a landmark: a genuinely dark, star-poor patch of sky is rare enough that it stands out, and once you have it, you can count outward from its corners to find neighboring constellations. It's a useful test of your own sky, too — the more stars you can pick out inside that box on a given night, the darker and steadier your conditions actually are, a rough gut-check before you go hunting anything fainter.

What is actually inside that empty-looking box

It is not empty at all once you have a telescope. M15 is a dense, bright globular cluster — a tight ball of ancient stars — sitting near Enif. Stephan's Quintet, catalogued as HCG 92, is a compact group of interacting galaxies, genuinely faint and a serious deep-sky target rather than a casual one. NGC 7331 is a spiral galaxy often compared to our own Milky Way in shape and size, though from Earth it appears as a small, dim smudge without real aperture behind the eyepiece. None of the three are casual naked-eye or small-binocular targets the way the Great Square itself is — they reward exactly the kind of patient, dark-sky telescope work that the empty-looking box above them doesn't ask for at all.

Finding Pegasus in your own sky

Pegasus is a northern-hemisphere constellation and its best month is October, when it rides high in the evening and the Great Square is easy to spot even from a moderately light-polluted yard — it is one of the few shapes bright and large enough to punch through some glow. Once you have the square, Andromeda's chain runs off its northeast corner.

What this means for you tonight

Look for the Great Square first, not the horse — four stars of similar brightness forming a big, obvious box is a far easier target to spot than trying to trace hooves and wings that mostly aren't drawn by bright stars at all. October evenings are the best window; if you're checking outside that month, the square will still be up, just lower or higher depending on the hour. And if your own chart's rising sign happens to fall in this stretch of the ecliptic, that's the horizon patch worth watching on the night you were born, or on any night going forward — the sky map will show you exactly where.

Read what a constellation really is to understand why a "horse" can look like a box, and how star brightness works for what those magnitude numbers on Markab and Scheat actually mean. The chained princess who shares the square's corner star is in Andromeda: The Chained Maiden, and the hero whose sword-stroke created this horse is in Perseus: The Hero.