chromosphere
The chromosphere is a layer of the Sun's atmosphere located above the photosphere and below the corona. It is characterized by a reddish glow as seen during solar eclipses and is the region where solar filaments and prominences are observed.
Source: eclipse2017.nasa.gov
APODs including "chromosphere"
Prominences and Filaments on the Active Sun
15/06/2024
This colorized and digitally sharpened image of the Sun is composed of frames recording emission from hydrogen atoms in the solar chromosphere on May 15. Approaching the maximum of solar cycle 25, a multitude of planet-dwarfing active regions and twisting, snake-like solar filaments are seen to sprawl across the surface of the active Sun. Suspended in the active regions' strong magnetic fields, the filaments of plasma lofted beyond the Sun's edge appear as bright solar prominences. The large prominences seen near 4 o'clock, and just before 9 o'clock around the solar limb are post flare loops from two powerful X-class solar flares that both occurred on that day. In fact, the 4 o'clock prominence is associated with the monster active region AR 3664 just rotating off the Sun's edge.