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.
The Atchafalaya River in Louisiana is a major distributary of the Mississippi. The Mississippi River, looking south toward the city of St. Louis.(courtesy USGS). The Mississippi drains most of the area between the Rocky Mountains and the Appalachian Mountains, except for the area drained by the Great Lakes.ith its source Lake Itasca at 1475 feet (450 m) above sea level in Itasca State Park in northern Minnesota, the river falls to 725 feet (220 m) just below Saint Anthony Falls in Minneapolis. The Mississippi is joined by the Illinois River and the Missouri River at Saint Louis, and by the Ohio at Cairo, Illinois.