ocr: CORONA The outermost, sparse layer of a star's (in speech, usually the Sun's) atmosphere. The Sun's corona is best visible during solar eclipses. The Sun's corona reaches out millions of kilometres and its shape varies according to the sunspot cycle. The temperature of the Sun's corona is millions of degrees, although the surface beneath it is only 6,000°C. The heat is caused by energy being transterred into the corona from loops caused by Prominance Coronal the magnetic field. Streamer The sparse gas is heated by strong granues) Photoaphere electrical currents generated between these loops, w ...
