as·​ter·​ism | \ ˈa-stə-ˌri-zəm How to pronounce asterism (audio) \

Definition of asterism

1a : a group of stars that form a pattern in the night sky On October evenings, when the trees have shed their leaves and stars become visible through the twigs, our best-known asterism, the Big Dipper, passes under the north pole.— George Lovi

Note: The term asterism does not now usually refer to a constellation but to a star pattern that makes up part of a constellation or that includes stars from more than one constellation.

b : a small group of stars
2 : a star-shaped figure exhibited by some crystals by reflected light (as in a star sapphire) or by transmitted light (as in some mica)

Examples of asterism in a Sentence

Recent Examples on the Web This week in the night sky Winter Hexagon: One of the sky’s largest asterisms—a recognizable pattern of stars separate from a constellation figure—dominates the eastern sky this time of the year. National Geographic, "Can the Super Bowl go green?," 29 Jan. 2020 Specifically, the shooting stars will seem to come from just to the left of the bowl of the Big Dipper, the popular asterism that makes up part of Ursa Minor. Andrew Fazekas, National Geographic, "Meteor outburst predicted for this weekend: When and where to see it," 20 Dec. 2019 Look carefully below the cosmic pair for the bright asterism known as the Cosmic Teapot. Andrew Fazekas, National Geographic, "See Neptune at its best and more top stargazing in September," 1 Sep. 2019 An asterism is simply a set of stars that form a pattern familiar to the human eye as part of a larger group of stars. National Geographic, "Reality Check: You Can’t Actually Name Stars for David Bowie," 18 Jan. 2016 In this case the asterism is made up of stars from the constellations Libra, Virgo, Centaurus, and Triangulum Australe. National Geographic, "Reality Check: You Can’t Actually Name Stars for David Bowie," 18 Jan. 2016 The seven stars that form the lightning pattern from Bowie’s album is in fact called an asterism. National Geographic, "Reality Check: You Can’t Actually Name Stars for David Bowie," 18 Jan. 2016 Many constellations display unique geometrical shapes and asterisms. Mike Lynch / Sky Watch, Twin Cities, "Sky Watch: The Winter Triangle is perfectly perfect this time of year," 5 Feb. 2017 As the days go on in February, the comet will quickly make a loop around the distinct Circlet asterism, a star pattern nestled within the constellation Pisces, the fishes. Andrew Fazekas, National Geographic, "Lunar Eclipse and 10 More Can’t-Miss Sky Events in February," 1 Feb. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'asterism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of asterism

1598, in the meaning defined at sense 1a

History and Etymology for asterism

Greek asterismos, from asterizein to arrange in constellations, from aster-, astēr

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Time Traveler for asterism

Time Traveler

The first known use of asterism was in 1598

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Statistics for asterism

Last Updated

15 Feb 2020

Cite this Entry

“Asterism.” Dictionary, Merriam-Webster, Accessed 8 Apr. 2020.

More from Merriam-Webster on asterism

Rhyming Dictionary: Words that rhyme with asterism Encyclopedia article about asterism

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