Mercury
Appearance
Mercury is the innermost planet of the Solar System. It is a terrestrial planet characterized by a small radius, high density, and close proximity to the Sun.
Mercury is discussed in planetary science, celestial mechanics, and comparative planetology.
Scope
Orbital properties and physical classification.
Status
Mercury has been observed telescopically since antiquity and has been studied through spacecraft missions. Models of its interior structure and thermal history continue to be refined.