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You just made me spend 5 minutes wondering if sundials would work on the equator, and if so, do they go counter-clockwise or clockwise during which parts of the

You just made me spend 5 minutes wondering if sundials would work on the equator, and if so, do they go counter-clockwise or clockwise during which parts of the year. Also, a fun fact: even if you have a wall-mounted sun dial (which was common in the ancient era) it still moves clockwise in the northern hemisphere, even though noon would be near the bottom of the clock.

jaggederest 6y ago
Of course they do. On the equinox it would follow a straight line through the middle of the pointer with times marked on it. At other times of the year, they behave Northerly in the northern summer and Southerly in the southern summer. Always west-to-east, though, obviously.
- minikites 6y ago
  And around noon near the equinox, there's no shadows at all: https://en.wikipedia.org/wiki/Lahaina_Noon https://en.wikipedia.org/wiki/Lahaina_Noon https://boingboing.net/2017/04/13/lahaina-noon-when-the-sun-is.html https://boingboing.net/2017/04/13/lahaina-noon-when-the-sun-...
  - yencabulator 6y ago
    Even an approximation of that is quite convincing. In the right time of year, palm trees in Los Angeles have their shadows pretty darn perfectly centered, and if the top of the tree is narrow the shadow is nearly invisible.
colanderman 6y ago
A sundial on the equator has a horizontal gnomon (oriented north-south), and the shadows move underneath it from west to east. (There is of course a slight curve in one direction or the other based on the seasons.) See e.g. https://en.wikipedia.org/wiki/Sundial#/media/File:Sundial,_Singapore_Botanic_Gardens.jpg https://en.wikipedia.org/wiki/Sundial#/media/File:Sundial,_S...
WalterBright 6y ago
I spent some time in Australia a few years ago. My sense of time and direction got totally confused, because the sun went the "wrong" direction in the sky. It was surprisingly disconcerting to me, I did not realize how much I oriented myself by the sun. It was only made worse by the Australians driving on the "wrong" side of the road :-) I was one disoriented man.

jaggederest 6y ago

Of course they do. On the equinox it would follow a straight line through the middle of the pointer with times marked on it. At other times of the year, they behave Northerly in the northern summer and Southerly in the southern summer. Always west-to-east, though, obviously.

minikites 6y ago
And around noon near the equinox, there's no shadows at all: https://en.wikipedia.org/wiki/Lahaina_Noon https://en.wikipedia.org/wiki/Lahaina_Noon https://boingboing.net/2017/04/13/lahaina-noon-when-the-sun-is.html https://boingboing.net/2017/04/13/lahaina-noon-when-the-sun-...
- yencabulator 6y ago
  Even an approximation of that is quite convincing. In the right time of year, palm trees in Los Angeles have their shadows pretty darn perfectly centered, and if the top of the tree is narrow the shadow is nearly invisible.

colanderman 6y ago

A sundial on the equator has a horizontal gnomon (oriented north-south), and the shadows move underneath it from west to east. (There is of course a slight curve in one direction or the other based on the seasons.) See e.g. https://en.wikipedia.org/wiki/Sundial#/media/File:Sundial,_Singapore_Botanic_Gardens.jpg https://en.wikipedia.org/wiki/Sundial#/media/File:Sundial,_S...

WalterBright 6y ago

I spent some time in Australia a few years ago. My sense of time and direction got totally confused, because the sun went the "wrong" direction in the sky. It was surprisingly disconcerting to me, I did not realize how much I oriented myself by the sun. It was only made worse by the Australians driving on the "wrong" side of the road :-) I was one disoriented man.