September 11th, 2019

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  • med_cat

Wednesday word: asterism


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Sep. 3rd, 2019 | 07:46 am

asterism (AS-tuh-riz-uhm) - n., (astronomy) a group of stars that is not one of the traditionally established constellations; (mineralogy) a six-rayed star-shaped figure exhibited by some crystals in reflected or transmitted light; (typography) three asterisks in a triangular formation (⁂) used to call attention to a passage.

The first sense is the one I know best. The group can be part of a standard constellation (such as the Big Dipper, which is one part of Canis Major) or parts of several constellation (such as the Summer Triangle, which is the brightest stars of Lyra, Cygnus, and Aquila). The second is the star of a star sapphire:

Asterism in sapphire
Thanks, WikiMedia!

The third is now rarely used. First appears in the 1590s, from Greek asterismós, constellation, from astēr, star.