Sunspots are temporary phenomena on the Sun's photosphere that appear darker than the surrounding areas because they are regions of reduced surface temperature. While still extremely hot (around 3000-4500 K), they are significantly cooler than the surrounding photosphere (around 5778 K), causing them to emit less light and appear dark by contrast.
Sun Spots appear dark because they:
Asked in APPSC Draughtman 2008 · Topic: Heat and Thermodynamics (Blackbody Radiation and Laws (Stefan-Boltzmann, Wien's Displacement))
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