Thursday is the first day of spring, or the vernal equinox, in the Northern Hemisphere. During an equinox, the center of the sun is on the same plane as the equator. After the vernal equinox in March, the Northern Hemisphere tilts toward the sun until the June solstice, when the sun begins to migrate back south.

The first day of spring, also known as the vernal equinox, has arrived in the Northern Hemisphere on March 20, 2025.

It marks the coming of the new year in some cultures. But what is Nowruz, and why do people celebrate it? Thursday, March 20, 2025, marks the Persian New Year, or Nowruz, a holiday that's been celebrated for several millenniums,