Sunspot in active region 12585 as observed on 2016 September 5 with the CHROMIS instrument at the Swedish 1-m Solar Telescope.
The panels display images of the sunspot at different wavelengths positions within the Ca II K spectral line. The continuum intensity level is shown in the bottom-right panel. By scanning the wings of the Ca II K spectral line we can sample different heights in the atmosphere. This set of images reveal the appearance of the sunspot from the mid-chromosphere (top-left panel) to the photosphere (bottom-right panel).
Image credit: Göran Scharmer and Jaime de la Cruz Rodríguez (ISP, Stockholm University)
Sunspot observed in Ca II K spectral line
The same sunspot in three different layers
A sunspot observed in multiple spectral lines
The amazing chromosphere above an active region (1/3)
The amazing chromosphere above an active region (2/3)
The amazing chromosphere above an active region (3/3)