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.
Great Lakes watershed is nearly three times the size of the actual lakes, encompassing more than 767,000. square miles (GLIN, 2009). The St. Lawrence River flows 530 miles from Lake Ontario to the Gulf of St. Lawrence âwith a fall of 245 feetâ (USACE, 2007). According to the U.S. Army Corp of Engineers (USACE) âthe International Section of the river extends for a distance of 115 miles from Lake Ontario to St. Regis, New.