This is a short movie of the Sun at the minimum of solar activity. This images are collected in ultraviolet light (a wavelength of 195 Å or 19.5 nanometers) which is only visible to space-based instruments. In visible light, few to now sunspots would be visible. At solar minimum, we see few bright active regions. The mottled look is from small 'hot spots' which last less than 48 hours. There are dark regions at the top and bottom of the Sun (corresponding to the north and south solar poles) created by solar magnetic field lines that connect to the interstellar magnetic field. A similar dark region, below the solar equator, is called a coronal hole, where open magnetic field lines enable particles to stream away at high speeds.
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