Messier 83 or M83, also known as the Southern Pinwheel Galaxy and NGC 5236, is a barred spiral galaxy approximately 15 million light-years away in the constellation borders of Hydra and Centaurus. Nicolas-Louis de Lacaille discovered M83 on 23 February 1752 at the Cape of Good Hope. Charles Messier added it to his catalogue of nebulous objects (now known as the Messier Catalogue) in March 1781.

It is one of the closest and brightest barred spiral galaxies in the sky, and is visible with binoculars. It has an isophotal diameter at about 36.24 kiloparsecs (118,000 light-years). Its nickname of the Southern Pinwheel derives from its resemblance to the Pinwheel Galaxy (M101).