What would be the new clockwise?

[chakka35]

This may be an old chestnut; I have certainly thought about it for years:

If analogue clocks and watches, and all memory of them, disappeared, how would one define clockwise?
Unlike north, south, east and west which are absolute, clockwise is relative to the observer. If I rotate my hand in front of me in what is to me a clockwise direction it is anticlockwise to someone looking at me from the front. To a fly on the face of a clock the hands between him and the glass are going anticlockwise, and so on.

One definition is "the direction which the sun appears to take around the sky to an observer in the northern hemisphere looking south". Not exactly snappy. Or "the direction in which a normal screw is tightened". The word"normal" dilutes that one but is necessary to allow for left-handed screws.

Is there a natural object or phenomenon which moves in a circle and which can be viewed only from one direction? Something astronomical comes to mind, since it cn be viewed by us only from the earth. But what?

(Incidentally, have you noticed that , in the opening titles of Have I Got News For You?, the villain who is presumably supposed to be turning the pipeline off is actually turning it on?)

[jake-the-peg]

Chirality is typically defined as right handed and left handed.

Actually this is a very interesting question in science.

Imagine you cannot see an alien but only talk to him - you have to communicate which is left and which is right - how

For a long time it was thought impossible. But it turns out that some radioactive processes in a magnetic field are "handed" in this way breaking Chiral symmetry

No time to explian more at the moment but it is a deeply important finding - nobel prize winning actually

[chakka35]

Sorry, Jake, I did mean to post it in Science and have done so now. Would others please post any answers on that site please. Thank you.

[naomi24]

Thank God(/) for that Chakka. I was wondering how I was going to set about answering it! :o)

[willowman]

A friend had a similar discussion with his wife over tightening a nut. He used the "righty tighty, lefty loosey" phrase when doing something with his wife and she insisted he was still tightening it the wrong way and the phrase was wrong.
And in this case it obviously hinges on whether you are refering to the top of the nut or the bottom.
We thought that turning it to the right was turning it clockwise, his wife thought the opposite.
Of course, being DIY experts we men know we are right (or should that be clockwise?)

[willowman]

Oops, just realised I've answered the question in the wrong category.
Still asleep, sorry.