>According to Immanuel Velokovsky (and perhaps Zechariah
>Sitchen also), the year used to be 360 days long, back before
>solar-system catastrophes changed its orbit.
Ha! Even if this is true, it had to be so long ago that humans
certainly wern't around when it happened. A catastrophe large enough
to change the orbital speed of the earth by that much would have
destroyed every living thing. (by my count, the velocity change
would be 414 m/s, so if we assume an object moving in exactly the
right direction (opposite to earths), with a velocity the same as
earth (a counter-orbital, if you will), it would have to have a mass
of 4.13(10^22), or roughly 1/100th the mass of the earth. i.e. 2/3
of the moon's mass. Any actually possibly collision would require a
bigger mass, since the component of it's velocity in the wrong
direction would not have the necessary effect) I can only imagine the
results of an object moving at a relative speed of 60000 m/s with a
mass 2/3 of the moons crashing into the earth... I suspect it would
shatter the planet.
(on a related note, I think that in inter-star-system warfare,
planetary bombardment with large masses would be the most effective
weapon: one can set it up without ever getting closer than a few
millions of miles, and it's virtually unstoppable. Very effective as
well)
>Thus it seemed
>natural to divide the circle into 360 degrees, one degree being
>the size of arc travelled by the earth in one day. 360 also has
>the virtue of having many factors, thus being capable of all kinds
>of equal subdivisions. (As a member of the Dozenal Society
>[formerly the Duodecimal Society, I have a keen interest in such
>matters.)
This I agree with. If you keep reading the archives, you will
discover that the actual source of the 360 degree system is the
Babloyian (sp) number system, which (apparently) was base 60. Why
*that* was so, I don't know. Perhaps because 60 was so conveniant,
what with so many factors.
>There are better ways to measure the circle, but that
>is another story.
This depends on what you mean by "better". There are more "natural"
ways to measure it, but they involve transendentals (e.g. 2*Pi), and
nobody likes working with those...
ERiC