Solar facula

Sun's faculae. Dark regions are sunspots and the brighter speckled regions around them are faculae. Although image is in grayscale, it correctly presents true white color of Sun's photosphere.

Solar faculae are bright spots in the photosphere that form in the canyons between solar granules, short-lived convection cells several thousand kilometers across that constantly form and dissipate over timescales of several minutes.

Faculae are produced by concentrations of magnetic field lines. Strong concentrations of faculae appear during increased solar activity, with or without sunspots. Faculae and sunspots contribute noticeably to variations in the solar constant. The chromospheric counterpart of a facular region is called a plage.[1][2][3][4]

  1. ^ Keller, C. U.; Schssler, M.; Vgler, A.; Zakharov, V. (20 May 2004). "On the Origin of Solar Faculae". The Astrophysical Journal. 607 (1): L59–L62. Bibcode:2004ApJ...607L..59K. doi:10.1086/421553.
  2. ^ Solov'ev, A A; Kirichek, E A (1 February 2019). "Structure of solar faculae". Monthly Notices of the Royal Astronomical Society. 482 (4): 5290–5301. doi:10.1093/mnras/sty3050.
  3. ^ Kostyk, R. I. (February 2013). "What are solar faculae?". Kinematics and Physics of Celestial Bodies. 29 (1): 32–36. Bibcode:2013KPCB...29...32K. doi:10.3103/S0884591313010030.
  4. ^ Hirzberger, J.; Wiehr, E. (August 2005). "Solar limb faculae". Astronomy & Astrophysics. 438 (3): 1059–1065. Bibcode:2005A&A...438.1059H. doi:10.1051/0004-6361:20052789.