Vibrant red hues are the result of anthocyanins, pigments that are produced in the fall. As green fades, the leave’s other pigments, such as the orange and yellow of carotenoids shine through. Leaves change their wardrobes in response to chilly temperatures and less light (as days begin to shorten) they stop producing chlorophyll, the green pigment that helps leaves capture sunlight to power photosynthesis. One of the most stunning signs of Autumn is the turning of the leaves. The word “ harvest” comes from the Old Norse word haust, which means “ to gather or pluck.” As people moved to the cities, “harvest” fell out of use and city dwellers began to use “ fall of the leaf,” which was shortened to “ fall.” Before these terms, the period was called “ harvest.” While Americans typically use the word “ fall,” the British use the word “ autumn,” though both terms date around the 16th century.

Instead, it the tilt of Earth’s rotational axis, which is angled at around 23.5 degrees, that creates seasons.Īutumn is derived from the French, which came from the Latin autumnus, the Roman name for this season. The Earth’s orbit around the Sun has very little effect over the Seasons on Earth. As Earth continues its path around the sun, days become shorter and nights become longer. The term equinox comes from the Latin words aequus, meaning equal and nox, meaning night.Īutumn begins when the center of the sun crosses Earth’s equator. The first day of autumn, the autumnal equinox, has 12 hours of daylight and 12 hours of darkness. The reason the equinoxes and solstices don’t always come on the same day is that Earth doesn’t circle the sun in exactly 365 days. And the last day of autumn 2020 will be on Monday, December 21st. The 1st day of autumn 2020 in Northern Hemisphere will be on Tuesday, September 22nd.

Fall autumn