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    At last, the earliest sunset arrives. The evenings start getting lighter from today!

    Banned
    Shame it still gets darker in the mornings for a couple more weeks

    10 Comments

    Isn't it the 21st, Winter Solstice?

    Original Poster Banned

    Banana79;3786176

    Isn't it the 21st, Winter Solstice?


    No, shortest day is the 21st (Winter Solstice).

    Earliest sunset is today. Latest sunrise is 1st Jan.

    timeanddate.com/wor…y=1

    Thanks wasn't aware of that. Have a good day!:santa:

    http://i44.tinypic.com/sqp05k.jpg

    Original Poster Banned

    lol - fingers crossed :-D

    its quite cosy though the darkness! maybe im odd!!

    csiman;3786210

    No, shortest day is the 21st (Winter Solstice). Earliest sunset is today. … No, shortest day is the 21st (Winter Solstice). Earliest sunset is today. Latest sunrise is 1st Jan.http://www.timeanddate.com/worldclock/astronomy.html?n=136&month=12&year=2008&obj=sun&afl=-11&day=1



    Wow, I didn't know that, great knowledge!!! :shock:

    ok wow.. im lost.. explain...

    Original Poster Banned

    red_one;3786953

    ok wow.. im lost.. explain...


    I think we need an astronomer to explain why the earliest sunset / latest sunrise don't occur on the shortest day. Most people think it does.

    I know the earth is on a slight tilt from its axis facing the sun but this won't explain it.

    Original Poster Banned

    I must be bored ;-)

    LATEST SUNRISE, EARLIEST SUNSET, AND THE 'EQUATION OF TIME'.
    [SIZE=-1]People are often puzzled by the fact that the dates of earliest sunset and latest sunrise do not coincide with the shortest day of the year (which is on or around 21st December in non-tropical northern latitudes). At latitude 25N, latest sunrise occurs just before mid-January, and earliest sunset is around the end of November. And at 50N, the date of earliest sunset is approximately 13th December, while latest sunrise is experienced at the end of December.[/SIZE]

    [SIZE=-1]Two quite separate factors contribute to this apparently strange behaviour:[/SIZE]

    [SIZE=-1]1. The Earth's speed of movement round the sun is not uniform. This causes variations in the sun's apparent rate of passage through the constellations - which is fastest during December/January, and slowest around June/July. Thus, sometimes the sun goes ahead of what may be called its 'normal' or 'mean' position; at other times it falls behind[/SIZE][SIZE=-1].[/SIZE]

    [SIZE=-1]2. The sun's week-to-week migration across the starry firmament is tied to the ]Ecliptic Line. However, times of sunrise, noon and sunset (being determined by Earth's daily rotation) relate more easily to the sun's ]Celestial Longitude - whose labels (along the Celestial Equator) are direct projections out from Earth's equator. But the 23½-degree angle between our equatorial plane and the ecliptic - usually modifies the sun's speed of progress parallel to the (more important) Celestial Equator. The greatest reductions occur in late March and late September. These seasonal fluctuations can cause dawn and dusk to come early (or late).[/SIZE]
    [SIZE=-1]Adding together those two contributing influences, produces a double-waved curve with a minimum near 11th February (when the sun is said to be 14 minutes 'behind schedule'), and a maximum near 3rd November (when it is just over 16 minutes 'ahead of schedule'). Thus, times of sunrise (and indeed sunset) from January to March are later than they would be if Earth's orbit was circular and if our spin-axis was 'upright'. And from September till late December, those times are earlier than they 'should' be. (*However, remember that when sunset is 'later than normal', the sun is actually further ahead than 'normal' in its migration across the firmament - which is from west to east).[/SIZE]
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