Fall Equinox (First Day of Fall)

Discussion in 'Misc Events' started by PopUpSteve, Sep 22, 2016.

  1. PopUpSteve

    PopUpSteve Administrator

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    Malvern, PA
    September Equinox
    There are two equinoxes every year - in September and March - when the sun shines directly on the equator and the length of day and night is nearly equal. Seasons are opposite on either side of the equator, so the equinox in September is also known as the "autumnal (fall) equinox" in the northern hemisphere. However, in the southern hemisphere, it's known as the "spring (vernal) equinox".

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    Why is it called equinox?
    On the equinox, night and day are nearly exactly the same length - 12 hours - all over the world. This is the reason it's called an "equinox", derived from Latin, meaning "equal night".

    [smg id=4569]
    The Earth's position during the September equinox (ill. not to scale).

    However, even if this is widely accepted, it isn't entirely true. In reality equinoxes don't have exactly 12 hours of daylight

    The September equinox occurs the moment the sun crosses the celestial equator - the imaginary line in the sky above the Earth's equator - from north to south.

    This happens either on September 22, 23, or 24 every year. On any other day of the year, the Earth's axis tilts a little away from or towards the Sun. But on the two equinoxes, the Earth's axis tilts neither away from nor towards the Sun, like the illustration shows.
     
  2. silvermickey2002

    silvermickey2002 Morris County, NJ

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    Sep 11, 2008
    Morris County, NJ
    Well, I guess it's official...Summer is over so I can now close our pool for the season... [:(]
     
  3. Snow

    Snow Well-Known Member

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    Ontaio
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  4. novagirl

    novagirl retired camper

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    Jul 13, 2011
    :'(

    Sent from my KFTHWI using Tapatalk HD
     
  5. kcsa75

    kcsa75 Member

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    XKPin likes this.
  6. XKPin

    XKPin There's no situation so bad it can't be made worse

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    Oct 28, 2016
    Gloucester, Virginia
    . . .do my eyes deceive me? Is it coming back??? Spring is here and the eternal darkness parts for the glory of impending summer, warmer weather, camping, beautiful night skies and . . .did I say summer?! I never thought the darkness would even!

    (Yes KCSA75, today even more than ever before!)
     

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