coronal hole
(cool, low-density portions of the Sun's corona)
A coronal hole is a portion of the Sun's corona
plasma that is cooler, darker, and has a lower density.
The corona is never uniform, always with such coronal holes,
which change over time. The holes emit higher velocity
solar wind and are contributors to solar weather.
(Sun,stars,corona)
Further reading:
https://en.wikipedia.org/wiki/Coronal_hole
https://www.swpc.noaa.gov/phenomena/coronal-holes
https://www.sidc.be/article/coronal-hole
https://www.spaceweatherlive.com/en/help/what-is-a-coronal-hole.html
Referenced by page:
Sun surface features
Index