Image credit: Hinode JAXA/NASA/PPARC
Uploader comment: This image of the solar 'chromosphere' was obtained on 11 November 2006 by the Hinode solar observatory, and reveals the fine-scale structure in the chromosphere that extends outward above the top of the convection cells, or granulation, of the photosphere (visible surface of the sun). The structure results from the interaction of hot ionised gas with the magnetic field.
The chromosphere a thin 'layer' of solar atmosphere 'sandwiched' between the sun's visible surface (or photosphere) and its outer atmosphere (or corona). The chromosphere is the source of ultra violet radiation.