March Equinox

Science Bite by Education Intern Delaney Osmond

If you are someone like me, who is not well-versed in cosmic occurrences, you may not know exactly what an equinox is. There are two equinoxes annually, one in March, and one in September. The March or ‘spring’ equinox is commonly considered the official start of the spring season. This year, the March equinox falls on March 20th.

Because of the rotation of the earth, and its revolution around the sun, the spot on the Earth’s surface directly beneath the sun, known as the subsolar point, moves along a north-south axis. The sun will reach the southernmost point of this axis during the winter solstice in December. In the northern hemisphere, this is the day with the shortest day length, and in the southern hemisphere, the longest day length. The inverse is true during the summer solstice in June.

An equinox occurs when the subsolar point is in the middle of the north-south axis, which is why there are two per year. During an equinox, the amount of light occurring in both the north and south hemispheres are equal. The term ‘equinox’ is derived from the Latin, ‘aequus’ meaning equal, and ‘nox’ meaning night, translating to “equal night”.

Cultures and religions across the world use the spring equinox to celebrate the coming of spring and determine the date of significant holidays such as Easter and Passover. How will you celebrate the start of spring and longer days to come? Visiting Carpenter Nature Center is a great way to celebrate out in nature.