First Day of Spring 2014: Vernal Equinox

In 2014, spring begins with the vernal equinox on March 20 at 12:57 P.M. EDT. Here’s more information about the equinox.

The Vernal Equinox

Ah, spring! This season brings increasing daylight, warming temperatures, and the rebirth of flora and fauna.

The word equinox is derived from the Latin words meaning “equal night.” Days and nights are approximately equal everywhere and the Sun rises and sets due east and west.

At the equinoxes, the tilt of Earth relative to the Sun is zero, which means that Earth’s axis neither points toward nor away from the Sun. (However, the tilt of Earth relative to its plane of orbit, called the ecliptic plane, is always about 23.5 degrees.)

Vernal Equinox Questions and Answers

Question: Why doesn’t the vernal equinox (equal night) on March 20 have the same number of hours for day and night?

Answer: Our former astronomer, George Greenstein, had this to say: "There are two reasons. First, light rays from the Sun are bent by the Earth's atmosphere. (This is why the Sun appears squashed when it sets.) They are bent in such a way that we are actually able to see the Sun before it rises and after it sets. The second reason is that daytime begins the moment any part of the Sun is over the horizon, and it is not over until the last part of the Sun has set. If the Sun were to shrink to a starlike point and we lived in a world without air, the spring and fall equinoxes would truly have ‘equal nights.’”