red dwarf


Definition of red dwarf

: a star having substantially lower surface temperature, intrinsic luminosity, mass, and size than the sun

Examples of red dwarf in a Sentence

Recent Examples on the Web Exoplanets have been found orbiting stars similar to our sun, or those lower in mass, like small red dwarf stars. Ashley Strickland, CNN, "Astronomers are changing the way we think of 'potentially habitable' planets," 4 May 2020 Its star, a red dwarf, is considerably smaller and cooler than our sun, a yellow dwarf, and its atmosphere is also different than ours. Washington Post, "Water, temperature right for life at another star’s planet," 11 Sep. 2019 But Kepler-1649c orbits a red dwarf star, much smaller and cooler than our sun. Ashley Strickland, CNN, "New potentially habitable exoplanet is similar in size and temperature to Earth," 15 Apr. 2020 The most common star in our galaxy is a red dwarf, smaller and dimmer than the Sun. John Timmer, Ars Technica, "Super-Earth at a nearby star is a Mercury-like hunk of rock," 20 Aug. 2019 Most notably, in 2017, Spitzer discovered four of the seven planets in the TRAPPIST-1 system, a red dwarf star 40 light-years away. Lily Katzman, Smithsonian Magazine, "Spitzer’s 16 Years of Scanning the Cosmos," 31 Jan. 2020 One of the other planets is a red dwarf about 40% as massive, 40% as wide and 50% as hot as Earth’s sun. Mike Wall, Scientific American, "NASA’s TESS Planet Hunter Finds Its First Earth-Size World in “Habitable Zone”," 7 Jan. 2020 Take the star dubbed GJ 3512 and its retinue of planets: The parent star is a red dwarf about one-eighth the mass of our own sun orbited by two gas giants (depicted in an image from a video simulation above). Sid Perkins, Science | AAAS, "Oddball solar system throws planet formation theories into question," 26 Sep. 2019 The red dwarf star Proxima Centauri is our closest stellar neighbor; the star system is a measly 4.2 light years from Earth and can be seen with the naked eye. Jennifer Leman, Popular Mechanics, "Is There a Hidden 'Super-Earth' Exoplanet Orbiting Our Closest Stellar Neighbor?," 16 Jan. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'red dwarf.' 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 red dwarf

1926, in the meaning defined above

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The first known use of red dwarf was in 1926

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Last Updated

16 May 2020

Cite this Entry

“Red dwarf.” Dictionary, Merriam-Webster, Accessed 29 May. 2020.

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