The last time the United States saw a total solar eclipse was in 1979 and on August 21, it will experience one again. In fact everyone in North and Central America and millions more in northern South America, will observe at least a partial eclipse. A solar eclipse occurs when the moon, as it is orbiting the earth, passes directly in between the earth and sun. This blocks the sun's light casting a shadow on the earth! There are three types of solar eclipses. A total solar ec