Spring gets its official start Friday in the Northern Hemisphere with the arrival of the vernal equinox. But what does that mean? The Earth's axis is tilted at an angle as it travels around the sun. On the equinox, the Earth's tilt is neither toward nor away from the sun, so both hemispheres get the same amount of sunlight. This means day and night last about the same amount of time. It also marks the start of a new season. Days will get a little longer every day in the Northern Hemisphere until the solstice in June.

Sunday marks the shortest day of the year in the Northern Hemisphere, signaling the start of astronomical winter. In the Southern Hemisphere, it's the longest day, marking the beginning of summer. The term "solstice" comes from Latin, meaning the sun's "pause" in its annual path. After the winter solstice, the sun begins to climb higher, and days gradually lengthen until late June. Solstices have been celebrated for ages, with monuments like Stonehenge aligning with the sun's paths. The equinox, in contrast, is when both hemispheres receive equal sunlight, leading to nearly equal day and night lengths.

Peak sunshine has arrived in the Northern Hemisphere — the summer solstice.

Spring is almost here — officially, at least.