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Old July 17th 05, 03:18 PM
George Dishman
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My thanks to Jeff and Jonathon for helping
figure out what Gerald is talking about.

wrote in message
oups.com...
George Dishman wrote:
wrote in message
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To George

The Earth orbital orientation (designated by the line division between
direct sunlight and its orbital shadow)


Gerald, there is no indication of sunlight and shadow
on the diagram you cite below. The shaded areas are
only to illustrate "equal areas".


Many do not have a feel for the material yet to others this will need
little explaining and they can fill in the numerous different
principles without prompting,diagrams or graphics.


A large part of the problem is that your descriptions
use terms that have little to do with what you are
saying. What you are saying is riddled with errors too
but the language problem makes it doubly difficult.
However, I think we have figured out part of this so
let's see if we can get somewhere.

The arrows in the diagram representing the change in orbital
orientation as the Earth orbits the Sun is designated in reality by the
division representing Sunlight and the Earth's orbital shadow.

http://geophysics.ou.edu/solid_earth...from_space.jpg


The line dividing the sunlight part from that
in shadow is called the terminator. What you
are calling "orbital orientation" seems to mean
the angle of the plane of the terminator to the
major axis of the Earth's orbit.

The arrows representing the change in orbital orientation from a polar
perspective indicate that this motion passing through a fixed axial
orientation generates seasonal changes.


I guess you mean this diagram

http://www.mhhe.com/physsci/astronom...ages/04f15.jpg

The arrows are something else but the rotation of the
plane of the terminator is important. It turns on
average by slightly less than 1 degree per day due to
Kepler's First law (it varies due to Kepler's Second
Law). That is 4 minutes per day and is the cause of
the difference between the solar day and the sidereal
day. The variation resulting from the second law
produces one aspect of the EoT.

turns in accordance with
Kepler's second law over the course of an annual orbit


That is too simplistic. The second law only gives the
rate at which the Earth moves along the orbital path.
The shape of the orbit as an ellipse with the Sun at
one focus is given by the _first_ law and it is the
motion of the Earth around the Sun first described
by Copernicus combined with the fixed tilt of the
axis of rotation that produces the seasons. Watch how
the Earth moves round the Sun in the animation below.


I went through months explaining how the early heliocentrists adapted
the equable 24 hour day to indepedent axial rotation at 15 degrees per
hour and 24 hours/360 degrees in total while you lot swear blind that
the value is 23 hours 56 min 04 sec working off the celestial sphere.


And I spent months patiently explaining that the two
numbers you quote are independent though related
through Kepler's First Law. To make them the same,
you have to discard Kepler (and Copernicus too of
course) and I'm not prepared to do that. You can if
you wish, and the fact that you cannot take his First
Law into account, but don't expect any astronomers
(or me) to do so.

I am not doing this again but if you lot can live with hemispherical
explanations of axial variations to the orbital plane and the Sun then
good for you.


You offer no alternative that can explain why it is
currently winter in the southern hemisphere. As long
as you reject reality, your failed descriptions will
be rejected in turn.

You spent a year arguing for variations in axial tilt to the Sun for
the Equation of Time purposes


No, I spent a year telling you that Kepler's
First Law explained the difference between the
solar and sidereal day, just as I have above
yet again. It was mainly others who argued
about tilt. They were right but I soon decided
you didn't know enough basic astronomy to follow
their arguments.

and now change your tune but I do not do
retail anymore you miserable creep,I can use you to show that
insincerity and incompetence is almost pandemic.


It only shows you never listened to what I said.

It is that change in orbital orientation passing through fixed axial
orientation that causes daylight/darkness asymmetry and seasonal
changes .


That is impossible since it would now be summer in
Australia and you have been told it is winter. Why
do you insist on demonstrating your ignorance by
constantly repeating something that has been proven
to be wrong? Listen carefully to this lecture on
how Copernicus' model produces the seasons if you
want to gain some basic understanding:

http://kids.msfc.nasa.gov/earth/seas...rthSeasons.asp


I do not condescend to anyone, ...


That's true, you exhibit nothing but blind
arrogance which is no doubt why your
understanding never improves, you just keep
trotting out the same old errors. Well if
you are so convinced you know it all, my
challenge remains, explain why it is now
winter in Australia but summer here in the
UK.

George