pro·​to·​star | \ ˈprō-tō-ˌstär How to pronounce protostar (audio) \

Definition of protostar

: a cloud of gas and dust in space believed to develop into a star

Examples of protostar in a Sentence

Recent Examples on the Web Material falling into the protostar will then begin to interact with its magnetic fields. Elizabeth Gamillo, Smithsonian Magazine, 16 Dec. 2021 Star birth begins with the formation of a protostar as gravity pulls gas clouds together in a process known as accretion. Elizabeth Gamillo, Smithsonian Magazine, 16 Dec. 2021 This creation story begins more than 4.5 billion years ago, when dust and gas from a giant molecular cloud gravitationally collapsed to create a protostar that would become our sun, surrounded by a spinning disk of gas and dust. Jonathan O'callaghan, Scientific American, 8 Dec. 2020 Masses of gas—mostly helium and hydrogen—within these stellar nurseries collapse under their own gravity and begin to heat up, forming a protostar. Jennifer Leman, Popular Mechanics, 13 June 2020 Because the dust in the nebulae obscures them, protostars can be difficult for astronomers to detect. Catherine Zuckerman, National Geographic, 20 Mar. 2019 One of these contracting masses of gas, known as a protostar, represents a star’s nascent phase. Catherine Zuckerman, National Geographic, 20 Mar. 2019 The forming star, or protostar, is about 11,000 light years away, in a much denser and more volatile region of the galaxy. Jay Bennett, Popular Mechanics, 21 Aug. 2016 In the center, the material clumped together to form a protostar that would eventually become the sun. Valerie Strauss, Washington Post, 9 Aug. 2017 See More

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

First Known Use of protostar

1947, in the meaning defined above

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The first known use of protostar was in 1947

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Cite this Entry

“Protostar.” Dictionary, Merriam-Webster, Accessed 4 Jul. 2022.

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