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The Solar Chromosphere

This SOHO/EIT EIT image details many solar features and some elongated prominences observed at chromospheric temperatures. Prominences are huge clouds of relatively cool dense plasma suspended in the Sun's hot, thin corona. Emission in this spectral line shows the upper chromosphere at a temperature of about 60,000 degrees K. Every feature in the image traces magnetic field structure. The hottest areas appear almost white, while the darker red areas indicate cooler temperatures.

Courtesy of SOHO/EIT consortium. SOHO is a project of international cooperation between ESA and NASA