Structure of the solar chromosphere

Abstract

The chromosphere is an intriguing part of the Sun that has stubbornly resisted all attempts at a comprehensive description. Thus, observations carried out in different wavelength bands reveal very different, seemingly incompatible properties. Not surprisingly, a debate is raging between supporters of the classical picture of the chromosphere as a nearly plane parallel layer exhibiting a gentle temperature rise from the photosphere to the transition region and proponents of a highly dynamical atmosphere that includes extremely cool gas. New data are required in order settle this issue. Here a brief overview of the structure and dynamics of the solar chromosphere is given, with particular emphasis on the chromospheric structure of the quiet Sun. The structure of the magnetic field is also briefly discussed, although filaments and prominences are not considered. Besides the observations, contrasting models are also critically discussed.