planetary nebula


: a usually compact luminous ring-shaped nebula that is composed of matter which has been ejected from a hot star at its center

Examples of planetary nebula in a Sentence

Recent Examples on the Web As a red giant, Arcturus is at the end of its life and will eventually transform into a planetary nebula. Elizabeth Gamillo, Discover Magazine, 5 Mar. 2024 Her relative obscurity is a reminder that this planetary nebula, located about 2,300 light-years away from Earth, will outlive us all, as well as any remnant memories of us. Eric Berger, Ars Technica, 12 Dec. 2023 Observations with the Near Infrared Camera (NIRCam), which is Webb's primary imager, also revealed extremely fine rays of light around the planetary nebula. Julia Musto, Fox News, 12 July 2022 Our Sun will eventually become a red giant in about 5 billion years, eventually progressing to an AGB before finally evolving into a planetary nebula with a white dwarf star at its center. Jennifer Ouellette, Ars Technica, 29 Mar. 2022 The colorful cloud in the image—somewhat misleadingly called a planetary nebula—is only a few thousand years old. Allison Parshall, Scientific American, 17 Mar. 2023 Abell 31 is a planetary nebula, a cloud of gas formed when a dying star expels winds of matter. Phil Plait, Discover Magazine, 13 Feb. 2012 For decades, astronomers have sought the lightest noble gas molecule, helium hydride, in the planetary nebula NGC 7027, shown in this composite image. Ken Croswell, Discover Magazine, 12 Dec. 2019 This expanding cloud of gas, called a planetary nebula, is the result of a dying star that is blowing off its outer layers. Jake Parks, Discover Magazine, 11 July 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'planetary nebula.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1785, in the meaning defined above

Time Traveler
The first known use of planetary nebula was in 1785

Dictionary Entries Near planetary nebula

Cite this Entry

“Planetary nebula.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2024.

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