The Column of Life

The Rite of Spring by Ann-Marie Imbornoni and Elissa Haney from infoplease.com March 20, 2012, is a date that most of us recognize as symbolic of changing seasons. As we welcome spring, people south of the equator are actually gearing up for the cooler temperatures of autumn. What Happens at the Equinox? Far from being an arbitrary indicator of the changing seasons, March 20 (March 21 in some years) is significant for astronomical reasons. On March 20, 2012, at precisely 0:14 AM EDT (March 20, 05:14 Universal Time), the Sun will cross directly over the Earth's equator. This moment is known as the vernal equinox in the Northern Hemisphere. For the Southern Hemisphere, this is the moment of the autumnal equinox. Equinox Means "Equal Night" Translated literally, equinox means "equal night." Because the Sun is positioned above the equator, day and night are about equal in length all over the world during the equinoxes. A second equinox occurs each year in September....

What Happens at the Equinox? Equinox Means "Equal Night" Translated literally, equinox means "equal night." The Sun is positioned above the equator, day and night are, therefore, about equal in length all over the world during the equinoces. The autumnal equinox will occur September 22 at 11:09 P.M. EDT. This date will mark the autumnal equinox in the Northern Hemisphere and the vernal equinox in the Southern. Reasons for the Seasons: These brief but monumental moments owe their significance to the 23.4 degree tilt of the Earth's axis. Because of the tilt, we receive the Sun's rays most directly in the summer. In the winter, when we are tilted away from the Sun, the rays pass through the atmosphere at a greater slant, bringing lower temperatures. If the Earth rotated on an axis perpendicular to the plane of the Earth's orbit around the Sun, there would be no variation in day lengths or temperatures throughout the year, and we would not hav...

The Rite of Spring by Ann-Marie Imbornoni and Elissa Haney from infoplease.com March 20, 2010, is a date that most of us recognize as symbolic of changing seasons. As we welcome spring, people south of the equator are actually gearing up for the cooler temperatures of autumn. What Happens at the Equinox? Far from being an arbitrary indicator of the changing seasons, March 20 (March 21 in some years) is significant for astronomical reasons. On March 20, 2010, at precisely 1:32 P.M. EDT (March 20, 17:32 Universal Time), the Sun will cross directly over the Earth's equator. This moment is known as the vernal equinox in the Northern Hemisphere. For the Southern Hemisphere, this is the moment of the autumnal equinox. Equinox Means "Equal Night" Translated literally, equinox means "equal night." Because the Sun is positioned above the equator, day and night are about equal in length all over the world during the equinoxes. A second equinox occurs each year on Septembe...

The Rite of Spring by Ann-Marie Imbornoni and Elissa Haney from infoplease.com March 20, 2010, is a date that most of us recognize as symbolic of changing seasons. As we welcome spring, people south of the equator are actually gearing up for the cooler temperatures of autumn. What Happens at the Equinox? Far from being an arbitrary indicator of the changing seasons, March 20 (March 21 in some years) is significant for astronomical reasons. On March 20, 2010, at precisely 1:32 P.M. EDT (March 20, 17:32 Universal Time), the Sun will cross directly over the Earth's equator. This moment is known as the vernal equinox in the Northern Hemisphere. For the Southern Hemisphere, this is the moment of the autumnal equinox. Equinox Means "Equal Night" Translated literally, equinox means "equal night." Because the Sun is positioned above the equator, day and night are about equal in length all over the world during the equinoxes. A second equinox occurs each year on Septembe...