March equinox

There are two equinoxes every year: one in March and one in September.

What is the Spring Equinox?

An Equinox is an astronomical event that happens twice, once in spring and once in autumn each year. During an equinox:

- The Earth's axis is not tilted toward or away from the Sun—it is perpendicular to the Sun's rays.

- This results in nearly equal day and night lengths across the globe.

During March, it is springtime in the Northern Hemisphere. In other words, on the March Equinox, it is springtime in the UK, the United States, Canada, Russia, India, and China, while it is autumn in Australia, Argentina, Chile, New Zealand, and South Africa, which are in the Southern Hemisphere.

In a nutshell:

March Equinox (around March 20):

• Northern Hemisphere: Spring begins

• Southern Hemisphere: Autumn begins

September Equinox (around September 22):

• Northern Hemisphere: Autumn begins

• Southern Hemisphere: Spring begins

So, when it is spring in the Northern Hemisphere during March, it is autumn in the Southern Hemisphere. And when September comes, the seasons switch—autumn starts in the North, and spring starts in the South.

Daylight saving time in the United States: With a mnemonic word play referring to seasons, clocks "spring forward, fall back"—that is, in springtime the clocks are moved forward from 2:00 a.m. to 3:00 a.m. and in fall they are moved back from 2:00 a.m. to 1:00 a.m.