Re: question about inclination of earth's axis.


Richard Tobin wrote:
In article <1148490621.352289.215420@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
<obhiee@xxxxxxxxxxx> wrote:
I'm curious. Suppose I were to be deprived of technology and had to
rely only upon my observation, and intuition, how would I know that
Earth's axis is inclined at an angle instead of being perpendicular?

Apart from the absence of seasons, if the earth's axis was
perpendicular to the ecliptic, the angle between the sun and the pole
star (assuming there was one) would always be 90 degrees.

-- Richard

I absolutely detest trivia because I well know how it becomes a
nuisance rather than a tool but it is approriate here .

If the distance from the Earth to the Sun is 1 inch,the distance from
Earth to polaris,using the same comparison, is over 40 miles . (431 *
62 240 AU).Try triangulating that one !.

A reasonable and responsible astronomer would approach the matter
differently.The comparative size of Venus and Earth and the transit of
Venus provides a more realistic idea of the size of our parent star -

http://www.oldstarlight.com/Venus%20Transit%206-8-4.jpg

It is almost impossible to impress on another the energy output of our
Sun across a distance of 93 million miles except to acknowledge that
radiation from the enormous celestial object is almost constant,half
the Earth receives that energy and the other half is in its own orbital
shadow -

http://geophysics.ou.edu/solid_earth/notes/solar_system/slides/earth_from_space.jpg

It takes men to consider things in correct geometric perspective,the
enormity of the Sun's energy output replaces referencing the Earth
axial orientation against the Sun never mind to Polaris .Assigning
changing orbital orientation and the behavior of axial rrotation
passing through that change is a fresh and productive way to approach
this material.

.

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