Re: question about inclination of earth's axis.


William Hamblen wrote:
On 24 May 2006 10:10:21 -0700, 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?

How did the ancients know that the axis of Earth is not perpendicular,
but inclined ?

By looking at the apparent path of the Sun in the sky. The sun is
high at noon in Summer, low at noon in Winter and midway during the
Spring and Autumn. It is just as if the orbit of the Sun was in a
plane inclined at 23-1/2 degrees to the plane of the Earth's equator
(in the geocentric planetary systems of the day).

Dreyer's History of Astronomy from Thales to Kepler has good coverage
of Greek astronomy.

I watched a good documentary on climate chaos on the BBC last
night,good coverage by David with the appropriate concern for
increasing CO2/Temperature signatures and their effects.

Asking people to change their behavior is a worthy sentiment however
who is going to change you direction in thinking when assigning the
astronomical causes.You just described a variable tilting Earth to the
Sun using hemispherical descriptions based on meteorological weather
patterns (seasons).You used the tilt of the Earth to do the job that
most intelligent people would know emerges from orbital changes in the
Earth's position.

Do you think ,as entire ecosystem's collapse that those who are
suffering from climate imbalances that they will congratulate you for
bringing precession into a discussion on annual climate norms,not
because of anything good but because you can.To describe
meteorological weather patterns using astronomical causes was fine in
the 17th century but not in the 21st.The human contribution to climate
change is too great to ignore and without the ability to distinguish
between climate norms due to the astronomical cycles and the
relationship between the motions and orientations of the Earth and the
signatures from human activity then what is the point ?.

Assigning change in orbital orientation to the Earth against fixed
axial orientation is no big shock to genuine people ,to see people
assign an axial/equatorial tilt to the Sun would be shocking if it were
not so depressing.God forbid any of you ever acquire anything like a
conscience in this matter,the disappointment would be enough to
supersede anything like climate concerns.It means people can no longer
think.

.

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