Days Getting Longer

Wallace1492
Wallace1492 Posts: 3,707
edited December 2009 in Commuting chat
Did anyone notice that the daylight was longer today than yesterday, by approx 1 min 23 secs?
"Encyclopaedia is a fetish for very small bicycles"

Comments

  • Oddjob62
    Oddjob62 Posts: 1,056
    Yup... loved every minute of it :)
    As yet unnamed (Dolan Seta)
    Joelle (Focus Expert SRAM)
  • merkin
    merkin Posts: 452
    I too loved every minute and 23 seconds of it! :P
  • Fireblade96
    Fireblade96 Posts: 1,123
    Me too - I really hate the days getting shorter, and it's a real mental boost to know that we've turned the corner :-)
    Misguided Idealist
  • Porgy
    Porgy Posts: 4,525
    Wallace1492 wrote:
    Did anyone notice that the daylight was longer today than yesterday, by approx 1 min 23 secs?

    you should have posted this in the mundane observations thread. :P
  • jonginge
    jonginge Posts: 5,945
    Been getting lighter in the evenings for the past ten days. I've enjoyed that ;)
    FCN 2-4 "Shut up legs", Jens Voigt
    Planet-x Scott
    Rides
  • iain_j
    iain_j Posts: 1,941
    Damn. I enjoy riding in the dark with my own little personal pool of light.
  • N0bodyOfTheGoat
    N0bodyOfTheGoat Posts: 5,851
    Sorry to burst your bubble, but Classic FM news informed me and other listeners of the winter solstice celebrations going on at sunrise today...

    Apparently, due to our calendar and bits like leap years, the shortest day was calculated to be on the 22nd and not the 21st of December this year! :lol:

    (But, apart from that, I did comment to me better half that we still had daylight in Southammpton at 1630 today)
    ================
    2020 Voodoo Marasa
    2017 Cube Attain GTC Pro Disc 2016
    2016 Voodoo Wazoo
  • CiB
    CiB Posts: 6,098
    The Winter solstice was on Monday at 17:47, which is when the sun was at its most southerly point as seen from earth (obviously :) ). Now I'm no astrologist but surely this means that the rate at which the days have been shortening has now stopped, having almost been stopped for a few days now as the earth's axis gradually stops going in one direction and starts to move in the other. Or maybe God has done a handbrake turn in this dodgy weather. Conversely the rate of increase will now start from zero as of Monday 21st and will increase until the Spring solstice in March, when the rate of increase hits a max, but days still get longer but at a slower rate. In June it all swings around again and starts to go the other way.

    So - arriving breathlessly at my point - the hours of daylight won't have been significantly different from a week or so ago until Monday and on into this week.

    If you know better pls say so. My knowledge of this derives from delivering The Leicester Mercury as a yoof, and keeping track of the lighting up times that used to be printed on the front page. I'm pretty sure that that the increase / decrease was never more than 3 minutes per day. Has the world changed since then?
  • Wallace1492
    Wallace1492 Posts: 3,707
    ChrisInBicester wrote:
    The Winter solstice was on Monday at 17:47, which is when the sun was at its most southerly point as seen from earth (obviously :) ). Now I'm no astrologist but surely this means that the rate at which the days have been shortening has now stopped, having almost been stopped for a few days now as the earth's axis gradually stops going in one direction and starts to move in the other. Or maybe God has done a handbrake turn in this dodgy weather. Conversely the rate of increase will now start from zero as of Monday 21st and will increase until the Spring solstice in March, when the rate of increase hits a max, but days still get longer but at a slower rate. In June it all swings around again and starts to go the other way.

    So - arriving breathlessly at my point - the hours of daylight won't have been significantly different from a week or so ago until Monday and on into this week.

    If you know better pls say so. My knowledge of this derives from delivering The Leicester Mercury as a yoof, and keeping track of the lighting up times that used to be printed on the front page. I'm pretty sure that that the increase / decrease was never more than 3 minutes per day. Has the world changed since then?

    Chris, you caught me out. Although, I would still believe that Tuesday at the point of sunset, will have been marginally later than on Monday, it will not be 1min 23 sec. We will not get that rate for a few weeks yet. The rate of change is at the maximum at the spring equinox, but it is not a huge difference.
    "Encyclopaedia is a fetish for very small bicycles"
  • CiB
    CiB Posts: 6,098
    It's the rate of change that matters. It's obviously zero twice each year, December & June, and also at a max on two occasions, in March & September.

    It follows that as we're talking planets and large solar bodies, sudden changes can be discounted. All things being equal the rate would describe a tidy sine wave graph, but as the earth spins a little faster in Winter IIRC and its orbit around the sun is more elliptical than circular, the graph would probably be squeezed in places to make it less than a sine wave. If only there were some means of looking this sort of info up, perhaps on a connected network of computers with an easy search portal. And if only I wasn't supposed to be rushing through some much needed changes to a core app this afternoon. Displacement activity I think it's called.
  • Wallace1492
    Wallace1492 Posts: 3,707
    ChrisInBicester wrote:
    It's the rate of change that matters. It's obviously zero twice each year, December & June, and also at a max on two occasions, in March & September.

    It follows that as we're talking planets and large solar bodies, sudden changes can be discounted. All things being equal the rate would describe a tidy sine wave graph, but as the earth spins a little faster in Winter IIRC and its orbit around the sun is more elliptical than circular, the graph would probably be squeezed in places to make it less than a sine wave. If only there were some means of looking this sort of info up, perhaps on a connected network of computers with an easy search portal. And if only I wasn't supposed to be rushing through some much needed changes to a core app this afternoon. Displacement activity I think it's called.

    The rate of change is maximum at the poles, and dissipated through to the equator. i am not familiar with rate of spin being faster in winter (i am presuming northern hemisphere winter). The orbit os the Earth will also be affected slightl;y by the moon, although it orbits round us, there is also a gravitational pull on the earth from Moon, and this throws out the Earths orbit slightly.

    This website is interesting, suggests Tuesday was 1 second longer thank Monday for London (daylight time). So my original post was 1 min and 22 sec out!!

    http://www.timeanddate.com/worldclock/astronomy.html?n=136&month=12&year=2009&obj=sun&afl=-11&day=1
    "Encyclopaedia is a fetish for very small bicycles"
  • Alinshearah
    Alinshearah Posts: 339
    The days are getting longer. BOOOO!!! I've been enjoying my P7 touch
  • Jay dubbleU
    Jay dubbleU Posts: 3,159
    Interestingly the BBC Weather site gives sunset time for Tuesday as 16.03 and for today as 16.01
  • Porgy
    Porgy Posts: 4,525
    Jay dubbleU wrote:
    Interestingly the BBC Weather site gives sunset time for Tuesday as 16.03 and for today as 16.01

    I believe that it starts getting light earlier now - but continues getting dark earlier for a little while

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