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Stars and Sticks| Abbreviation | Gem |
|---|---|
| Meaning | Twins |
| Pronunciation Guide is based on “Pronouncing Astronomical Names,” published in 1943 by the American Astronomical Society. | JEM-ih-nye |
| Genitive The genitive is the Latin possessive form used in star names. For example, Alpha Orionis means “the Alpha of Orion.” | jem-ih-NOR-um |
| Best Month | February |
| Visibility | Northern |
| Origin | AncientThese figures are rooted in the classical Greek and Mesopotamian traditions cataloged by Ptolemy in the 2nd century AD. |
| Author | PtolemyPtolemy, a 2nd-century Greco-Egyptian astronomer, cataloged the 48 classical constellations in his landmark work, the Almagest. These form the core of the 88 modern constellations recognized today. |
| Type | constellation |
| Difficulty | Easiest |
| Description | The divine twins Castor and Pollux were born from the same mother, Leda, but had different fathers — mortal King Tyndareus fathered Castor while Zeus himself fathered Pollux, making one twin mortal and the other immortal. When Castor was slain in combat, the grief-stricken Pollux begged Zeus to share his own immortality — and Zeus, moved by such devotion, placed them together in the sky forever. Fittingly the constellation's brightest star is not Pollux (the immortal twin) but Castor (the mortal) — which is actually a remarkable sextuple star system, six stars in three pairs all orbiting each other at about 52 light-years from Earth. |
| Meteor Shower | Geminids |
| Peak Month | December |
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Monthly sky charts courtesy of What's Out Tonight? — Copyright ©2026 Ken Graun. Star charts are optimized for mid-latitudes of the Northern Hemisphere. Click a chart to view or download the PDF. For guidance on using the chart, or to purchase a planisphere and astronomy books, visit kenpress.com.
Images: NOIRLab/NSF/AURA/E. Slawik · IAU and Sky & Telescope · Stellarium — Full credits →
