Solar phenomena

Solar activity: NASA's Solar Dynamics Observatory captured this image of the X1.2 class solar flare on May 14, 2013. The image shows light with a wavelength of 304 angstroms.

Solar phenomena are natural phenomena which occur within the atmosphere of the Sun. They take many forms, including solar wind, radio wave flux, solar flares, coronal mass ejections,[1] coronal heating and sunspots.

These phenomena are believed to be generated by a helical dynamo, located near the center of the Sun's mass, which generates strong magnetic fields, as well as a chaotic dynamo, located near the surface, which generates smaller magnetic field fluctuations.[2] All solar fluctuations together are referred to as solar variation, producing space weather within the Sun's gravitational field.

Solar activity and related events have been recorded since the eighth century BCE. Throughout history, observation technology and methodology advanced, and in the 20th century, interest in astrophysics surged and many solar telescopes were constructed. The 1931 invention of the coronagraph allowed the corona to be studied in full daylight.

  1. ^ Siscoe, George L.; Schrijver, Carolus J., eds. (2010). Heliophysics : evolving solar activity and the climates of space and earth (1. publ. ed.). Cambridge: Cambridge University Press. ISBN 9780521112949. Retrieved 28 August 2014.
  2. ^ Giampapa, Mark S; Hill, Frank; Norton, Aimee A; Pevtsov, Alexei A. "Causes of Solar Activity" (PDF). A Science White Paper for the Heliophysics 2010 Decadal Survey: 1. Retrieved 26 August 2014.