Spring and fall equinoxes fall at the halfway point between winter and summer solstices, occurring "when the sun crosses the equator and day and night are of roughly equal length, everywhere in the world," according to the Washington Post.
The nearly-equal 12 hours of light and darkness can be attributed to the Earth's lack of an axial tilt on the day of the equinox. In fact, according to Glastonbury Patch, the word equinox is derived from the Latin words aequus, meaning equal, and nox, meaning night.
Celebrate the changing seasons on Martha's Vineyard with a nature walk at Felix Neck Wildlife Sanctuary Saturday at 10 a.m. Free to members and $5 to non-members, it's a great way to bid farewell to summer and shake hands with fall.
Do you mark the equinox in any special way? Tell us in the comments.