A solar eclipse observed over Grand Canyon National Park in May 2012. Grand Canyon National ParkV
On Monday, August 21, people living in the continental United States will be able to see a total solar eclipse.
Humans have been alternatively amused, puzzled, bewildered and sometimes even terrified at the sight of this celestial phenomenon. A range of social and cultural reactions accompanies the observation of an eclipse. In ancient Mesopotamia (roughly modern Iraq), eclipses were in fact regarded as omens, as signs of things to come.
For an eclipse to take place, three celestial bodies must find themselves in a straight line within their elliptic orbits. This is called a syzygy, from the Greek word “súzugos,” meaning yoked or paired.
Solar lunar eclipse diagram. Tomruen (Own work) via Wikimedia Commons, CC BY-SA
From our viewpoint on Earth, there are two kinds of eclipses: solar and lunar. In a solar eclipse, the moon passes in between the sun and Earth, which results in blocking our view of the sun. In a lunar eclipse, it is the moon that crosses through the shadow of the Earth. A solar eclipse can completely block our view of the sun, but it is usually a brief event and can be observed only in certain areas of the Earth’s surface; what can be viewed as a total eclipse in one’s hometown may just be a partial eclipse a few hundred miles away.
By contrast, a lunar eclipse can be viewed throughout an entire hemisphere of the Earth: the half of the surface of the planet that happens to be on the night side at the time.