WhatTheStar

Constellations · Constellation · Geminorum · Gem

Constellation

Gemini

The twins Castor and Pollux, side by side. Castor, it turns out, is six stars in one.

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Genitive
Geminorum
Area
514 square degrees · 30th of 88
Brightest star
Pollux · magnitude 1.16
Naked-eye stars
119 brighter than magnitude 6.5
Highest at midnight
early January

Myth

Castor was mortal and Pollux immortal. When Castor was killed, Pollux asked to share his immortality; Zeus let them spend their days alternately in the heavens and the underworld, together.

Discovery

In 1781, from his garden in Bath, William Herschel found a new planet near the feet of the Twins — Uranus, the first planet discovered since antiquity. Pluto was found here too, in 1930.

Look for

Every December the Geminid meteors radiate from near Castor — one of the richest showers of the year.

Words used here

Stars in it with a story

Deep-sky objects in it

Asterisms it lends stars to

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