Sun torch

from Wikipedia, the free encyclopedia

Sun flares , also known as faculae (Latin: facula = small torch) or plages (French: light beaches ), are areas on the sun that have an increased brightness and temperature (about 7000 ° C) compared to the normal visible surface .

Sun flares are typically located near sunspots , which they often indicate a few days in advance. The mean lifespan is around 15 days; it is therefore usually longer than that of the associated spots. The torches are excited to glow by strongly variable magnetic fields , which are also the cause of sunspots.

Sun flares spread out flat and in long lines of light in the chromosphere . They can therefore be observed particularly well at the edge zones of the solar disk , where the brightness of the photosphere below is already subdued ( edge darkening ). Best seen are solar flares in the red light of hydrogen - spectral lines , but also in the calcium - wavelengths  K2 and K3. The photographic observation takes place by means of spectroheliograms . Occasionally, very bright flares in white light can also be observed in the center of the solar disk , for example if a flare occurs there during observation .

Exact research into solar flares began in the 1950s by Ten Bruggencate and Otto Kiepenheuer . The latter recorded it for the first time at different altitude levels and suspected variable magnetic fields as the cause.

literature

  • Otto Kiepenheuer: The sun (= understandable science, 68). Springer-Verlag, Berlin 1957, pp. 89-100.
  • Allan Fallow et al: The sun . Time-Life books, Amsterdam 1992, chapter Chromosphere and p. 37.

Web links

Wiktionary: Sun torch  - explanations of meanings, word origins, synonyms, translations