please empty your brain below

Another aspect to consider is time zones. The sun is highest in the sky at noon at only one specific longitude. However, the GMT timezone is quite wide, so when it's noon in the middle of the timezone it "should" be 11:30 am at the western edge of the timezone and it "should" be 12:30 pm at the eastern edge of the zone.
It's the dark mornings that depress me. And those will keep getting darker for quite a while.
For similar (but opposite) reasons, London's latest sunrise occurs around New Year's Eve. Still almost three weeks to go for that :(
I got up this morning determined to enjoy today as it is my birthday. I now feel a little cheated! I cheered up when I spotted a rare typo.
Excellent post.

I too dislike the dark mornings - which is why I wouldn't favour tinkering with GMT/BST arrangements to give more light in the evenings (but extend morning darkness).
When did we start insisting that everything needs to run to the same time each day despite the large variations in sunlight?

Is it a bad idea for the average working / school day to be shorter in winter and longer in summer?

I've never been to Alaksa or Norway but if I went 24 hours without real sunlight I would prefer to hibernate, bearing in mind that shops might still need to stay open if I am not going to hunt for my own food.
The sundial on the Stock Exchange in Paternoster Square is calibrated to show "clock" noon. The vertical extent of the figure 8 shape relates to how high the sun is at noon, and the horizontal extent how far east or west of the meridian it is due to the "equation of time".

If we measured time against the "fixed" stars we wouldn't need the equation of time: the earth takes 23h56m04s to spin on its axis relative to them. the remaining not-quite-four minutes (on average, but actually varying by up to fifteen minutes) is the parallax effect caused by us having moved almost 1 degree of arc round the sun, so the stars appear to have moved relative to the sun.
http://fineartamerica.com/featured/the-noon-sundial-at-the-london-stock-exchange-steve-taylor.html

Linkie to the stock exchange sundial omitted from previous comment
As someone who is far more bothered by early sunset than late sunrise, this post has cheered me up no end. Afternoons are getting lighter from now on. Yippee.
I sometimes wonder what would happen if we allocated time zones to change with exact lines of longitude, and made East London an hour ahead of West London. Imagine the chaos :)
Interesting stuff - and cheery that the afternoons are getting lighter at last. The passive-aggressive bleakness of the English winter has only hit me since I moved out to the countryside - in London one is kind of sheltered a bit by buildings and lights and roast chestnut sellers...

Karen - I think it was only the coming of the railways that led to a standardisation of time across the UK. But it would not be as much as n hour's difference between East and West London... The Cathedral in Oxford claims that it runs on "Oxford time" of old, which is 5 minutes behind Greenwich.
Well, that all depends on how many time zones we choose to have. Obviously before Railway Time, each town had their own local time. Actually, maybe we should all go back to that. That would cause some serious chaos. It's not as if trains always leave or arrive on time in the first place :D
But sundials actually tell the correct time even less frequently in the UK. They rely on the presence of sunlight!
Brilliant explanation.
Karen - the time zones (when not modified to fit national boundaries, so mainly in international waters) go in 15 degree bands, one of which is centred on the Greenwich Meridian (so 7.5 degrees east and west).
http://www.infoplease.com/images/timezones.gif

so even if we changed to the maritime time zones, only Co Fermanagh and the extreme western Hebrides (Isles of Barra and North Uist) which fall just west of 7.5 degress west, would be in a different time zone to the rest of the UK.
You could of course go for a finer graduation, but as DG has pointed out the time of solar noon varies over the year by up to half an hour anyway, even if you stand still.
Great - some astronomy! The figure 8 is the analemma, which tracks where the Sun appears in the sky at the same time each day over a year. See http://en.wikipedia.org/wiki/Analemma
"Bear with me on this one" "And if all this has gone completely over your head, don't worry." The first tells us one thing...the second sums it up. Though the "earliest sunset of the year is today" is only true if you happen to live where the earliest sunset of the year is today. If you live elsewhere it has already occured or has yet to occur. Which makes me wonder where if anywhere does the earliest sunset of the year actually occur on the 21st of December? Or has it all really gone over my head...
A very interesting post. I look forward to the extra second of sunshine on Saturday afternoon, which I think could be a sunny day.
I am always much happier after December 21st. knowing that every day is getting lighter for longer.
Does that mean it's really all uphill, in the best possible way, from today instead of 21st?
Let me guess, are the four days a year that sundials are accurate, on the two solstices and two equinoxes by any chance?

Fascinating post either way! I'm another one delighted that the evenings are now getting slowly lighter again! Roll on summer!
Peculiarly, the four days when sundials tell the right time (when the sun is highest at noon) are 16 April, 15 June, 1 September and Christmas Day.
Off topic. What is the RSS feed address for the site. Suffering from PC issues so redoing my RSS feeds

dg writes: Orange square, top right of page.
http://diamondgeezer.blogspot.com/atom.xml

Sadly there are people who are going to read significance into what DG has just posted about Christmas Day.
@Cornish Cockney
as shown here
http://en.wikipedia.org/wiki/Equation_of_time#mediaviewer/File:Tijdvereffening-equation_of_time-en.jpg

"It's to do with the Earth's orbit not being a circle, but an ellipse. It's to do with the Earth travelling at different speeds at different points in its orbit."
The two phenomena are one and the same - as Kepler observed and Newton explained. Orbital velocity depends on distance from the primary - as you go up, you slow down, and vice versa: that's conservation of energy.
Do the four days when sundials tell the right time vary from year to year? And, if so, by how much?
Thanks. :)
@1153pm
Yes they do: like all astronomical events related to the earth's orbit, (equinoxes, solstices etc) these events are instants in time, not entire days, and occur every 365.2425 days. Thus each year they occur 5h49m12s later than the previous year - leap days being introduced every fourth year to stop the events drifting by more than a day. Thus the winter solstice this year is at 23:03 GMT on December 21st, and next year it will be at 04:38 GMT on Dec 22nd. The date can also depend on which time zone you are in: in most of Europe the winter solstice this year will occur at 00:03 on Dec 22nd.

Question - how did the first nineteen comments get made before the time DG put the post up?
^ Karen

"Imagine the chaos :)" ...don't have to imagine it. Anyone that travels from parts of west London to east London or vice-versa will know that at times one might as well be in different time-zones given how long the journey can take ;(
For everyones information, these calculations have been carried out by orthodox Jews for centuries. The sunset time marks the beginning of the Sabbath and festivals, the prayer times are calculated by "seasonal hours", dividing the sunrise to sunset period into 12 "hours" which vary according to the season, the noon and midnight marks also come into play - and of course it all varies according to location.
The BBC have also noticed this http://m.bbc.com/news/magazine-30549149
Indeed, Mark - was just about to say that the BBC were copying DG, like others have been known to do.
Don't you mean that the evenings get longer and longer as we get more daylight until mid June?

dg writes: Oops, yes.
Only took 10 days to spot...











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