First Day of Spring 2013: Vernal Equinox

Spring begins with the vernal equinox at 7:02 A.M. (EDT) on March 20, 2013 in the Northern Hemisphere. Here’s more about the start of spring, signs of spring, and stunning spring photos!

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.)

See your local Sun rise and set times—and how the day length changes!

Find last spring frost dates.

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.’”

View the reason for the seasons and why the seasons change.

Question: According to folklore, you can stand a raw egg on its end on the equinox. Is this true?

Answer: One spring, a few minutes before the vernal equinox, several Almanac editors tried this trick. For a full workday, 17 out of 24 eggs stood standing. Three days later, we tried this trick again and found similar results. Perhaps 3 days after the equinox was still too near. Try this yourself and let us know what happens!

Signs of Spring

Spring is also the time when worms begin to emerge from the earth, ladybugs land on screen doors, green buds appear, birds chirp, and flowers begin to bloom. The vernal, or spring, equinox signals the beginning of nature’s renewal in the Northern Hemisphere.

You can track when the seasons change by recording animal behaviors and the way that the plants grow. Listen to the new sounds and observe what you hear and see.

How do you know that spring is coming? Share your comment below!

Spring Pictures

Our ecards are great photographs to send to family and friends.
Browse our full Spring Ecard Gallery.

Tree Peony After Rain. Send as ecard!

Spring Folklore and Verse

One swallow does not make a spring.

Bluebirds are a sign of spring; warm weather and gentle south breezes they bring.

In spring, no one thinks of the snow that fell last year.

Don’t say that spring has come until you can put your foot on nine daisies.

Spring-time sweet!
The whole Earth smiles, thy coming to greet.

When does summer start? Click here to see our Seasons page which lists the first day of each season.

Related Articles

• Blog: Signs of Spring
• Poll: Observing the Signs of the Seasons
• First Day of Summer 2013: The Summer Solstice