photosphere

noun

pho·​to·​sphere ˈfō-tə-ˌsfir 

1

: a sphere of light or radiance

2

: the luminous surface layer of the sun or a star

photospheric

ˌfō-tə-ˈsfir-ik 

-ˈsfer-

adjective

Examples of photosphere in a Sentence

Recent Examples on the Web

Poitevin’s latter analysis revealed that thanks to the prominences, for him, the partial eclipse began 4 minutes and 7 seconds before the moon began to cross the photosphere. —Jamie Carter, Forbes, 8 Oct. 2024

Eclipses are said to begin when the moon crosses the sun’s disk, its photosphere, but through an H-alpha telescope, the observer sees the chromosphere, so the eclipse always starts slightly earlier. —Jamie Carter, Forbes, 8 Oct. 2024

The sun’s photosphere is full of millions of bubbles formed through convection. —Ashley Strickland, CNN, 11 Sep. 2024

The Parker probe saw the entire thing—from the CME's generation, to its emission from the sun's surface (or photosphere), to its propagation in the space between our star and our planet. —Rebecca Boyle, Scientific American, 1 Mar. 2024

Word History

Etymology

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

First Known Use

1664, in the meaning defined at sense 1

Kids Definition

photosphere

noun

pho·​to·​sphere ˈfōt-ə-ˌsfi(ə)r 

: the shining surface of the sun or a star

photospheric

ˌfōt-ə-ˈsfir-ik 

-ˈsfer-

adjective