He did this by relating the light-year to the Astronomical Unit â the Earth-sun distance. One Astronomical Unit, or AU, equals about 93 million miles (150 million km). Another way of looking at it: the Astronomical Unit is a bit more than 8 light-minutes in distance. A light beam takes 8 minutes to travel the 93 million miles (150 million km) from the sun to the Earth.
Lake Superior sits between Ontario, Canada and New York. Lake Ontario is mainly fed by the waters of Lake Erie, which are transported via the Niagara River. Lake Ontario drains into the St. Lawrence River. Lake Michigan is the third largest of the Great Lakes and the only one entirely within the United States.
Water from the Great Lakes drains into the St. Lawrence River, and therefore that ecosystem is directly affected by the quality and quantity of water from the Great Lakes. The Great Lakes basin supports a diverse, globally significant ecosystem that is essential to the resource value and sustainability of the region.