Final answer:
The corona is the outermost layer of the Sun's atmosphere, situated above the chromosphere and visible during a total solar eclipse. It is characterized by high temperatures and extends millions of miles from the Sun's surface, playing a key role in solar wind production.
Step-by-step explanation:
The outermost layer of the Sun's atmosphere, located above the chromosphere, is the corona. The corona is typically visible only during a total solar eclipse, when the Moon blocks the Sun's bright photosphere and allows the pearly white glow of the corona to be seen. This part of the Sun's atmosphere consists of sparse gases that extend millions of miles outwards from the Sun's surface and reveals fascinating structures such as coronal loops and coronal mass ejections (CMEs).
The corona is incredibly hot, with temperatures reaching up to and exceeding a million degrees Kelvin. Despite its high temperatures, the corona is less dense than the underlying layers of the Sun's atmosphere, which is why its light is comparatively feeble. The corona's role is crucial in influencing space weather events and producing the solar wind that streams throughout our solar system.