Summer has come and gone: fall starts Saturday
Druids celebrate the Autumn equinox on Primrose Hill on September 22, 2009 in London, England. The ceremony is one of three events staged by the order with the Spring Equinox ceremony at Tower Hill and the Summer Solstice held at Stonehenge.
Say goodbye to summer as the autumnal equinox – the beginning of fall – begins Saturday.
The equinox occurs when the sun travels directly over the Earth's equator making day and night equal in length.
Equinox means "equal light" in Latin.
Space.com pointed out that this observation is not quite correct, however, as daylight is still a little longer given that "night" is measured by the moment the sun dips below the horizon.
In fact, even before it seems to have gone down, it is simply an optical illusion that keeps it hovering and twilight carrying on.
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The autumnal equinox is the first day of autumn in the northern hemisphere only.
In the southern half of the world spring has sprung once again.
The autumnal equinox doesn't always fall on the same day.
It sometimes falls on the 23rd or 24th due to Earth's irregular orbit, said LiveScience.
LiveScience also reported the strange fact that humans react very oddly to seasonal changes.
This includes high sexual drive during the early summer and, as everyone, knows, seasonal affective disorder during winter.
The website also pointed out that plants and animals repond as well – leaves will soon turn a golden brown, fall from trees and crunch beneath our feet.