[net.rumor] Equinocturnal Egg Standing Phenomenon

jnw (03/29/83)

Armchair physicists and Ph.D.s, explain this one!
    I've been told that the only time you can balance an egg on its big end
is at the equinox.  I've seen demonstrations of the fact that eggs do
balance on end at the equinox and have never seen an egg balance on end
when it is not the equinox.
    Is the folklore concerning the equinox correct?  If so, WHY?  Several
wild ideas have been posed around here concerning the juxtaposition of the
earth's axis and the sun at the equinox, but they don't seem to hold water.
    I think this is probably of general interest if someone has an
explanation, so if you KNOW why this works (or if it's a lie) please
reply to the net.
Thanx.
				joe wilson
				Univ. of Virginia
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lynnef (03/30/83)

In my college Physics class, I had an Chinese professor.  He walked in one
day (in the Spring sometime), and announced that it was a special Chinese
holiday on which an egg could be stood on end.  He stood up about 3 eggs
and then proceeded with the lecture.  Sometime later in the month I
succeeded in standing an egg on its end.  It was not an equinox at the time.
I think it has to do with luck and magic fingers myself.

kdmoen (03/31/83)

	I've seen demonstrations of the fact that eggs do balance on end at the
	equinox and have never seen an egg balance on end when it is not the
	equinox.
Who performed these demonstrations?  Under what conditions?
It's fairly simple to balance an egg on end on an apparently smooth
table top.  All you need to do is (secretly) deposit a few grains of
sand or salt on the table, under the egg.  I've done the trick myself.

I find it hard to believe that the equinox has any real stabilizing
effect on eggs.
	Doug Moen, {allegra,decvax,utcsrgv}!watmath!kdmoen

halle1 (04/01/83)

I think it more likely that the egg was hard boiled, and you were tricked.

rhm (04/01/83)

I'm sure that assymetric tidal forces are a factor.  These questions are
discussed at considerable length in a book named "The Theory of the Top"
by Felix Klein (translated from the German "Theorie des Kreisels").