Ontario Lacus (Titan)

Lake on the border between Canada and the United States.

Ontario Lacus is a lake composed of methane, ethane and propane near the south pole of Saturn's moon Titan. Ontario Lacus has a surface area of about 15,000 square kilometers about 20% smaller than its terrestrial namesake, Lake Ontario in North America. In April 2012, it was announced that it may be more like a mudflat or salt pan. (wikipedia entry)

A lacus is a "lake" or small, dark plain with discrete, sharp boundaries. On Titan they are named after lakes on Earth, preferably with a shape similar to the lacus or lacuna on Titan.