The spring equinox will occur at 5:01 a.m. EDT on Thursday. Here's what to know about the start of the spring season.

The word equinox comes from two Latin words meaning equal and night. That’s because on the equinox, day and night last almost the same amount of time — though one may get a few extra minutes, depending on where you are on the planet.

Let's welcome Spring with the Vernal Equinox. Vernal means spring. This week marks the vernal equinox -- the beginning of astronomical spring in the Northern Hemisphere and astronomical fall (or autumn) in the Southern Hemisphere.