The "burning" Caloris Basin (HR)

The largest basin on Mercury (about 1300 Km - or 800 miles across) was named Caloris (Latin for "heat") because it is one of the two areas on the Planet that face the Sun at perihelion.

The Image Processing Lab at NASA's Jet Propulsion Laboratory produced this photomosaic using computer software and techniques developed for use in processing planetary data.
The Mariner 10 spacecraft imaged this Region during its initial flyby of the Planet.