A lightning bolt is about five times hotter than the surface of the Sun.
Why it is true
The temperature of a lightning bolt can reach 30,000 kelvin, while the Sun's surface is around 5,500 kelvin. The heat lasts only fractions of a second, but it is enough to melt sand and turn it into glass. That is why a lightning bolt is five times hotter than the solar surface.
Source: NOAA
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