Sky and Mercury are vastly different entities. Sky refers to the celestial expanse above the Earth, encompassing the atmosphere and outer space as visible from the surface. It's filled with phenomena like clouds, sunlight, stars, and planets. Mercury, on the other hand, is the smallest planet in our solar system, closest to the sun. It's a rocky, cratered world with extreme temperature variations and virtually no atmosphere. Sky is an environment, while Mercury is a physical object within the vastness of space.
