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Which constellation has this IAU abbreviation?

Constellations reference chart

All 88 constellations recognized by the International Astronomical Union (IAU), each with its official three-letter abbreviation, predominant celestial hemisphere, and brightest star. Filter by hemisphere to narrow the list.

Showing 88 of 88 constellations

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The 88 IAU constellations

A constellation is a recognized pattern of stars on the celestial sphere. Since 1922 the International Astronomical Union (IAU) has divided the entire sky into 88 official constellations, each covering a defined region so that every star belongs to exactly one. This page lists all 88 — from Andromeda to Vulpecula — with each constellation's official three-letter IAU abbreviation (And, Ori, UMa), the celestial hemisphere it mainly sits in, and its brightest star, from famous ones like Sirius, Rigel, and Vega to fainter alpha stars.

Constellations by hemisphere

Constellations are grouped here by the celestial hemisphere they predominantly occupy: Northern (visible mainly from the northern sky, e.g. Ursa Major, Cassiopeia), Southern (mainly the southern sky, e.g. Crux, Centaurus), and Equatorial (straddling the celestial equator and visible from most of the world, e.g. Orion, Aquila, Virgo). Use the hemisphere filter above the chart to see just the constellations for the sky you can observe.

How the quiz works

Each round shows one three-letter IAU abbreviation and four possible constellation names. Pick the name you think matches; the quiz marks it right or wrong, reveals the correct answer with its hemisphere and brightest star, and keeps a running score, current streak, and best streak for the session. Press Next constellation for a new card or Reset score to start over. Every abbreviation and answer choice is selected with the Web Crypto API, entirely in your browser. For a single random constellation instead of a quiz, try the Random Constellation generator.