Sinus Meridiani is a feature name for an albedo feature on Mars stretching east-west just south of that planet's equator. It was named by the French astronomer Camille Flammarion in the late 1870s. It has a diameter of 1622 km, and its center is located at 7.12 S and 4 E.
Read more about Sinus Meridiani: Observational History, Meridiani Planum, What Opportunity Rover Discovered About Rocks and Minerals At Meridiani Planum, More Images From Sinus Meridiani