pho·​to·​sphere | \ ˈfō-tə-ˌsfir How to pronounce photosphere (audio) \

Definition of photosphere

1 : a sphere of light or radiance
2 : the luminous surface layer of the sun or a star

Other Words from photosphere

photospheric \ ˌfō-​tə-​ˈsfir-​ik How to pronounce photosphere (audio) , -​ˈsfer-​ \ adjective

Examples of photosphere in a Sentence

Recent Examples on the Web These are where large, beautiful plasma loops — commonly seen as solar prominences — extend far away from the Sun’s photosphere and can even enter the Sun’s corona. Ethan Siegel, Forbes, 8 June 2021 At its peak, the photosphere was moving at around 7 kilometers per second, reversing the outward push as the dimming of the star became more dramatic. Jennifer Ouellette, Wired, 18 June 2021 The findings last year showed that an outer layer of the star, called the photosphere, had begun unevenly accelerating outward right before Betelgeuse began to dim. Jennifer Ouellette, Wired, 18 June 2021 Coronal mass ejections are the largest, connecting the photosphere to the corona, where reconnection can cause an enormous release of energy. Ethan Siegel, Forbes, 8 June 2021 That friendly yellow photosphere boils like oatmeal and is pocked with dark magnetic storms (the infamous sunspots) that crackle, whirl and lash space with showers of electrical particles and radiation. New York Times, 28 May 2021 The scientists paired this data with measurements of the photosphere in the same stretch of the sun taken by the co-observing Hinode satellite. Chris Wright, Wired, 15 Mar. 2021 This type of photography is an incredible challenge due to the overwhelming light of the photosphere below. Mike Wehner, BGR, 8 Mar. 2021 In addition, there’s a tenuous, very hot plasma separated from the photosphere: the Sun’s corona, which is hundreds of thousands of kelvin, and the Sun’s chaotic, irregular magnetic field frequently connects the two. Ethan Siegel, Forbes, 26 Feb. 2021 See More

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

First Known Use of photosphere

1664, in the meaning defined at sense 1

History and Etymology for photosphere

photo- + -sphere; in sense 2 probably as translation of German Lichtatmosphäre

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Time Traveler for photosphere

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The first known use of photosphere was in 1664

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photo spread

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Cite this Entry

“Photosphere.” Dictionary, Merriam-Webster, Accessed 29 May. 2022.

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