Sept. 22
The northern hemisphere has two seasons at a time. In the northwest, the official first day of fall is September 21st. In the northeast, the official first day of fall is June 21st. Technically, though, if you looked at the real symptoms of fall, the first days of fall would be October 24th in the northwest and May 24th in the northeast.
The equinox is the only day of 12 hours of night and day. It Occurs every spring and fall.
The Sun is never ON the equator, it is above the equator twice a year - the spring equinox and the fall equinox.
fall equinoxin the southern hemisphere: march 21st-22ndin the northern hemisphere: September 21st-22ndspring equinoxin the southern hemisphere: September 21st-22ndin the northern hemisphere: march 21st-22nd
Fall in the US According to the website USA.gov, the first day of Fall (Autumn) in the US is Wednesday September 22, 2010, at 11:09 PM ET. (See Related links.)
In North America, the first day of fall is considered to be on September's equinox. Every year, there is another equinox around March 20.
The adjectives vernal and autumnal mean "of spring" and "of autumn (fall)" respectively. The equinox, when the day and night are even, occurs twice a year. Once in spring and once in autumn (fall) as we move from the extremes of the summer and winter solstices. Therefore we have a vernal equinox (in spring) and an autumnal equinox (in autumn/fall).
September 22nd
The northern hemisphere has two seasons at a time. In the northwest, the official first day of fall is September 21st. In the northeast, the official first day of fall is June 21st. Technically, though, if you looked at the real symptoms of fall, the first days of fall would be October 24th in the northwest and May 24th in the northeast.
the autumnal equinox
That is the Vernal Equinox; as opposed to the first day of Fall's Autumnal Equinox.
spring and fall equinox
technically fall starts on the exact same day every year, when the earth is in a particular part of the yearly orbit, the day is called the autumn equinox and is September 21st
This year it is September 22, at 5:18 pm, Eastern Daylight Time. This is the moment of the Autumnal Equinox.
The Vernal Equinox determines the first day of spring. The Autumn Equinox is what determines the first day of fall.
The equinox is the only day of 12 hours of night and day. It Occurs every spring and fall.
In the northern hemisphere, the autumnal equinox marks the first day of fall. An equinox happens twice a year, when the sun shines directly on the equator and the length of day and night is nearly equal.