The Seated Queen — a crown of five stars written across the Milky Way since the first eyes looked upward
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At a Glance
Written in ancient light
598Square degrees
25thLargest constellation
5Primary stars
~228Light-years to Schedar
∞Years visible from Earth
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Origin
The Vanity of a Queen
In Greek mythology, Cassiopeia was the vain and boastful queen of Aethiopia, wife of King Cepheus. Her fatal flaw was her pride — she dared claim that she and her daughter Andromeda were more beautiful than the Nereids, the sea nymphs beloved of Poseidon.
Poseidon, furious at the insult, sent the sea monster Cetus to ravage the kingdom's shores. The oracle of Ammon decreed the only appeasement was to sacrifice Andromeda to the beast — chained to a cliff above the crashing waves.
Perseus, returning victorious with Medusa's severed head, saw Andromeda and fell instantly in love. He slew Cetus and claimed her as his bride. Cassiopeia was placed among the stars — but as punishment, she spins eternally around the pole, sometimes hanging upside down as penance for her vanity.
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Principal Stars
Five points of the W
Cassiopeia's distinctive W (or M) shape is formed by five bright stars, each with its own unique character and story.
α · Alpha
Schedar
Magnitude 2.24 · 228 ly
A luminous orange giant and the brightest star in Cassiopeia. Schedar is derived from the Arabic for "breast," marking the queen's chest on ancient star maps.
β · Beta
Caph
Magnitude 2.28 · 54 ly
A white pulsating variable star that gently brightens and dims over a 2.5-hour cycle. It was once used as a prime meridian reference for celestial coordinates.
γ · Gamma
Gamma Cassiopeiae
Variable 1.6–3.0 · 550 ly
The central and most dramatic star of the W. A hot blue-white "shell star" spinning so rapidly it ejects material into a surrounding disk, causing irregular brightness changes.
δ · Delta
Ruchbah
Magnitude 2.68 · 99 ly
An eclipsing binary star — two white stars orbiting each other every 759 days. Its name derives from Arabic for "knee," and it sits in the region where the queen's throne is said to rest.
ε · Epsilon
Segin
Magnitude 3.35 · 410 ly
The faintest of the five principal stars, yet still prominent in the night sky. A blue-white giant lying at the edge of the W, anchoring the constellation's eastern tip.
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Observation
When to look up
Cassiopeia is circumpolar from mid-northern latitudes — it never sets below the horizon and is visible year-round. However, it reaches its highest point on autumn evenings, blazing overhead on October and November nights.
To find Cassiopeia, locate the North Star (Polaris) and look for the unmistakable W or M shape on the opposite side from the Big Dipper. No telescope is needed — the five primary stars shine clearly even in moderately light-polluted skies.
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Deep Sky Objects
Wonders hidden within
Cassiopeia lies along the band of the Milky Way, making it rich territory for deep-sky observers. Several spectacular objects await binoculars or a small telescope.
Open Cluster
Messier 52
~5,000 ly distant
A rich open cluster of roughly 200 stars appearing as a hazy glow to the naked eye. In a telescope it resolves into a stunning jewel box of blue-white and orange stars.
Open Cluster
NGC 457 — Owl Cluster
~7,900 ly distant
One of the finest open clusters in the sky. Two bright stars form the owl's gleaming eyes, with chains of fainter stars sweeping outward like outstretched wings.
Supernova Remnant
Cassiopeia A
~11,000 ly · Exploded c. 1680
The strongest radio source beyond our solar system — the expanding shell of a massive star that exploded around 1680. Invisible to the eye but spectacular in radio and X-ray observations.
Supernova of 1572
Tycho's Star
~8,000 ly distant
In 1572 a "new star" blazed in Cassiopeia so bright it was visible in daylight. Danish astronomer Tycho Brahe's meticulous observations helped overturn the Aristotelian view of immutable heavens.