Solar observatories study phenomena associated with the Sun. The Sun, being the closest star to earth, allows a unique chance to study stellar physics with high-resolution. It was, until the 1990s, the only star whose surface had been resolved. General topics that interest a solar astronomer are its 11-year periodicity (i.e., the Solar Cycle), sunspots, magnetic field activity (see solar dynamo), solar flares, coronal mass ejections, differential rotation, and plasma physics.
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