What astromony can do

I quite enjoyed reading about the magnification hobby and the
chestbeating financial contest between participants here but
personally I prefer Marty's or Barbara's homely observations of the
night sky and rely on images from Hubble,Keck or other large
telescopes to do my own research.

Beyond magnification,which is a valuable facet of astronomy,there is
work to be done such as a closer link between astronomy (specifically
the motions of the Earth) and terrestrial studies such as climate and
geology.Here is just one of the facets which is both productive and
enjoyable for those who can appreciate things for themselves and join
in the endeavor if they so choose and to the best of their abilities.

http://www.world-science.net/otherne...301_mantle.htm

It has been known for centuries ,or at least speculated,that the
rotation of the planet causes its overall shape to deviate from a
perfect sphere and the planet diameter across the Equator as opposed
to the polar diameter is greater by roughly 40 KM.The popular
explanation for the spherical deviation is unsatisfactory,basically a
line drawn from the center of the Earth is a crude sort of way -

http://www-istp.gsfc.nasa.gov/stargaze/Srotfram1.htm

The clue to the rotational details is actually in the geological
feature of the Mid Atlantic ridge allied with generalised rules for
rotating celestial bodies with viscous composition such as stars and
the molten interior of planets,the Earth being no exception.

A rotating stellar body with roughly the same mass has a 3-way
correlation -

1 - Maximum Equatorial speed

2 - differential rotation bands

3 - Spherical deviation

How to apply differential rotation to the Earth's interior as a means
to replace impractical use of thermally driven 'convection cell'
mechanism and explain the symmetrical creation of surface crust of the
mid Atlantic ridge,as the Americas and Europe/Africa are equidistant
from the ridge,is a delightful challenge.

The central band straddling the Equator is bounded North and South by
slower moving bands where the slower band lags the faster central
band,The creation of crust Westward towards the Americas is balanced
by the lag of the slower composition latitudinally below it thereby
creating an Eastward formation of crust.The band that is creating
crust Eastwards towards Europe/Africa is also moving faster than the
band beneath that thereby keeping continuity with crustal development
Westward and so a dynamical chain is set up between lag and advance
of bands due to their relative speeds hence the proportional creation
of new crust at the divergent boundary otherwise known as the Mid
Atlantic ridge -

http://www.ngdc.noaa.gov/mgg/image/crustageposter.gif

The orientation of the ridge alone indicates a rotational mechanism
for crustal dynamics but the strongest evidence is from observed
evidence of stellar rotation and the correlation between shape,maximum
equatorial speed and differential rotation.

Presently,the mechanism for crustal evolution/motion was a good guess
for 1928 data in the form of thermally driven 'convection cells'
which require no association with planetary shape or rotation,
however, modern imaging and interpretation of rotational dynamics
indicate a common mechanism which links planetary shape with plate
tectonics.

This post is designed for those who can take a wider view of astronomy
and no money can buy the kind of satisfaction derived from seeing
physical features explained or seeing the possibilities which a new
perspective introduces.

On Jan 28, 3:30*pm, Sam Wormley wrote:

Speaking of motions of the earth...

"The Earth rotates about its polar axis once a day
* *---From the Explanatory Supplement To The Astronomical Almanac (1992)

Once a day? Not once every *sidereal* day? Not once every 23 hours, 56
minutes, and 4 seconds?

Horrors! I've been wrong all these years about astronomy, and Mr.
Kelleher has been right all along!

Either that or they slipped up by oversimplifying...

John Savard

I quite enjoyed reading about the
magnification hobby and the
chestbeating financial contest between
participants here but personally I prefer
Marty's or Barbara's homely
observations of the night sky and rely on
images from Hubble,Keck or other large
telescopes to do my own research.

I happened upon this yesterday, and was just a bit confused by Gerald's
"prefer" ing my observations... (I'm assuming I'm the "Marty"
mentioned.) While it's always nice to find that someone has at least
mildly enjoyed my occasional simple rambles, Gerald has often expressed
his displeasure with such things as my earth centered coordinates,
(things rise and set, etc.) and my viewing things against a background
of fixed stars. I do these things because (1) I LIVE on the Earth, and
make my observations from it's surface, usually just outside my house,
and (2) I live on a human time scale, and for all practical purposes the
constellations are a handy way to find my way around the sky, and fun in
an historical context.
Oh well... What does one say....?
Marty

Sam Wormley wrote:

"The Earth rotates about its polar axis once a day and produces an
rotate clockwise."

---From the Explanatory Supplement To The Astronomical Almanac (1992)

Forget the sidereal thing, that's at least somewhat obvious. What in
the world do they mean by "produces an rotate clockwise"?

Going by the right hand rule for cross products and that sort of fun
mathematical stuff, the Earth orbits and spins counterclockwise.
--
Dave

On Jan 28, 10:43*pm, Sam Wormley wrote:
Sam Wormley wrote:
oriel36 wrote:
I quite enjoyed reading about the magnification hobby and the
chestbeating financial contest between participants here but
personally I prefer Marty's or Barbara's homely observations of the
night sky and rely on images from Hubble,Keck or other large
telescopes to do my own research.

Beyond magnification,which is a valuable facet of astronomy,there is
work to be done such as a closer link between astronomy (specifically
the motions of the Earth)...

Speaking of motions of the earth...

"The Earth rotates about its polar axis once a day and produces an
rotate clockwise.

* *Oops....

The Earth rotates about its polar axis once a day and produces an
apparent motion on the night sky about the celestial poles. In the
Northern Hemisphere the north celestial pole is elevated above the
horizon. Facing away from the elevated celestial pole, an observer sees
the Sun, Moon, planets, and stars rise in the east and set in the west.
They reach their highest altitude as they cross the local meridian.
When the observer turns to face the elevated celestial pole, stars
nearest the pole neither rise nor set. They become circumpolar and
cross the meridian each day once above the pole at their highest
altitude and once below the pole at their lowest altitude. In the
Northern Hemisphere, circumpolar stars appear to rotate about the north
celestial pole counterclockwise. In the Southern Hemisphere the effect
is reversed and they appear to rotate clockwise.



"Superimposed on the diurnal rotation is an annual rotation caused by
the Earth's orbiting the Sun. Since the stars are seen by the naked eye
after sunset, the constellations appear to move from east to west, and
to return to the same position after a year. Relative to the Sun, the
stars rise and set roughly four minutes earlier each day. In the course
of a month, the night sky appears to move two hours in right ascension
to the west. Also because of this orbital motion of the Earth, the
circumpolar stars in the Northern Hemisphere appear to rotate once a
year in a counterclockwise direction around the north celestial pole
and in a clockwise direction about the south celestial pole.

"The Moon moves in an orbit inclined to the ecliptic by 5.1 degrees;
the Moon makes one revolution about the sky from west to east in about
a month. During this period the phases on the Moon complete a cycle
from new to full and back to new. The orbit of the Moon is moving
around the ecliptic, so that other aspects of the Moon's position in
the sky, such as its maximum and minimum declination, change from one
month the next. It is important to know when the planets are in the
most favorable position for observation. The outer planets, for
example, are best seen around opposition. They are in their least
favorable position around conjunction.

"The inner planets are different--they are in their most favorable
position near greatest elongation, even though they are not at full
phase. At superior conjunction the phase is around full, but the
planets are difficult to see because they are further from Earth and
usually too close to the Sun. At inferior conjunction the inner planets
are nearest to the Earth, but again they are difficult to see because
their phase is small, and they are too close to the Sun.

"Often the times of phenomena need not have any great precision;
sometimes the nearest hour, day, or even the nearest week are
sufficient for observational purposes. The dates and times, however,
usually depend on the coordinate system. For historical reasons the
conjunctions and oppositions of planets have always been calculated in
geocentric ecliptic coordinates. On the other hand, the conjunctions of
planets with other planets, bright stars, or the Moon have always been
calculated using equatorial coordinates; the phenomena are then
observed more easily with an equatorially mounted telescope. In some
cases the times of phenomena have been defined as the maxima or minima
of the distances from the Sun or the Earth or the elongation from
another body. In such cases, the phenomena are independent of the
coordinate system".
* ---From the Explanatory Supplement To The Astronomical Almanac (1992)

I was wondering about the apparent typo as well; so it turned out to
be a fairly large elision.

This subsequent part of our original quote:

Superimposed on the diurnal rotation is an annual rotation caused by
the Earth's orbiting the Sun. Since the stars are seen by the naked
eye
after sunset, the constellations appear to move from east to west, and
to return to the same position after a year. Relative to the Sun, the
stars rise and set roughly four minutes earlier each day. In the
course
of a month, the night sky appears to move two hours in right ascension
to the west.

could also be taken as explaining the Earth's motions in the Solar
System in precisely the way Gerald Kelleher does, anticipating his
discovery of a "new motion" of the planets.

Given this, it does make me wonder if I'm being too harsh on his point
of view; maybe it is a legitimate (instead of confusing) way of
describing the Solar System. Certainly the conventional way _can_ be
confusing if not done with care - as the controversy with him points
out.

As it seems to be natural to think of the Moon as _not_ rotating,
rather than rotating in synchrony with its orbit around the Earth, it
does seem natural to speak of axial rotation as having a 24 hour
period. But given the tilt of the Earth's axis, such a 24-hour
rotation is a funny bent kind of rotation.

On the surface of Uranus, so favored by him as an example, it's hard
to see the synodic day as even having much practical meaning; during
the portion of the year when a part of the planet is alternately in
light and darkness, the interval between those periods will be the
sidereal day.

John Savard

On Jan 29, 4:10*am, (Marty) wrote:
I quite enjoyed reading about the
magnification hobby and the
chestbeating financial contest between
participants here but personally I prefer
Marty's or Barbara's homely
observations of the night sky and rely on
images from Hubble,Keck or other large
telescopes to do my own research.

I happened upon this yesterday, and was just a bit confused by Gerald's
"prefer" ing my observations... *(I'm assuming I'm the "Marty"
mentioned.) *While it's always nice to find that someone has at least
mildly enjoyed my occasional simple rambles, Gerald has often expressed
his displeasure with such things as my earth centered coordinates,
(things rise and set, etc.) and my viewing things against a background
of fixed stars.
*I do these things because (1) I LIVE on the Earth, and
make my observations from it's surface, usually just outside my house,

Try LIVE on a Moving Earth and those motions were determined by people
who looked out into the same celestial arena as you do now,the
difference is that they could put their observations of the planets in
proper context of where they exist in respect to the central Sun and
especially the Earth's position between Venus and Mars.

Now,I can ask you to determine whether Newton's view meshes with that
of Copernicus,Kepler and Galileo in recognising that as you LIVE on an
orbitally moving Earth,you can see that orbital motion in action as it
overtakes Jupiter and Saturn as we all head in the same direction
around the central Sun -

http://antwrp.gsfc.nasa.gov/apod/ima...2000_tezel.gif

That sequence represents a condensed view of Saturn and Jupiter taken
over many months against the same stellar background,you drop the
stellar background and then deal with the orbital motion of the Earth
against the motions of the other planets and then draw the only
conclusion possible .

I have yet to see a single individual here who can grasp that Newton
got the main argument for the Earth's orbital motion wrong and as his
views now dominate or rather ,infect, astronomy and you can bet your
bottom dollar that his version has serious consequences -

"For to the earth planetary motions appear sometimes direct,
sometimes stationary, nay, and sometimes retrograde. But from the sun
they are always seen direct.." Newton



and (2) I live on a human time scale, and for all practical purposes the
constellations are a handy way to find my way around the sky, and fun in
an historical context.
* * *Oh well... *What does one say....? *
* * * * * * * * * * * Marty

And the reasoning of Copernicus,Kepler and Galileo is not fun ?,what
does one say indeed.Even the geocentric astronomers could distinguish
between objects in their foreground and the background constellations*
but with Flamsteed's creation of the equatorial coordinate system,all
motions are fixed to the apparent motion of the stellar background
that you know as Ra/Dec observing which amounts to chaining all
observed motions of the planets,even the Sun,to the Earth's daily
rotation and the calendar system.You get your 'predictions' for
planetary positions alright but structural astronomy and the ability
to reason properly withers.





* 'THE ORDER OF THE HEAVENLY SPHERES '
"Of all things visible, the highest is the heaven of the fixed stars.
This, I see, is doubted by nobody. But the ancient philosophers wanted
to arrange the planets in accordance with the duration of the
revolutions. Their principle assumes that of objects moving equally
fast, those farther away seem to travel more slowly, as is proved in
Euclid's Optics. The moon revolves in the shortest period of time
because, in their opinion, it runs on the smallest circle as the
nearest to the earth. The highest planet, on the other hand, is
Saturn, which completes the biggest circuit in the longest time. Below
it is Jupiter, followed by Mars.

With regard to Venus and Mercury, however, differences of opinion are
found. For, these planets do not pass through every elongation from
the sun, as the other planets do. Hence Venus and Mercury are located
above the sun by some authorities, like Plato's Timaeus [38 D], but
below the sun by others, like Ptolemy [Syntaxis, IX, 1] and many of
the modems. Al-Bitruji places Venus above the sun, and Mercury below
it. " Copernicus

http://www.webexhibits.org/calendars...opernicus.html

On Jan 28, 10:30*pm, Sam Wormley wrote:
oriel36 wrote:
I quite enjoyed reading about the magnification hobby and the
chestbeating financial contest between participants here but
personally I prefer Marty's or Barbara's homely observations of the
night sky and rely on images from Hubble,Keck or other large
telescopes to do my own research.

Beyond magnification,which is a valuable facet of astronomy,there is
work to be done such as a closer link between astronomy (specifically
the motions of the Earth)...

Speaking of motions of the earth...


That's right Sam,the rotation of the Earth has geological consequences
and they are fairly detailed provided men can wean themselves off
referencing the Earth's rotation to an astrological 'fixed stars'
framework and treat rotation as an independent motion that it actually
is .The rotating viscous composition beneath the fractured crust is
not exempt for the generalised rules governing all rotating celestial
objects and specifically the observed feature of differential
rotation,it is the relative speeds between bands that causes the Earth
to deviate from a perfect sphere and provides the mechanism for
crustal evolution and motion.

http://geomaps.wr.usgs.gov/parks/plt...ticRidgeSM.jpg

The dramatic 'S' band which stretches the globe and follows the
rotational orientation of the Earth indicates the presence of a
rotational mechanism but it is the symmetrical generation of crust off
the ridge that really calls attention to the same dynamic which causes
the day and night cycle.As you are so busy referencing a 'solid' Earth
against an equidistant celestial sphere bubble you are unlikely to
appreciate the enormous effect rotational dynamics actually has on the
planet,not just the huge 40Km spherical deviation but the ability to
sever continents as the dramatic curves between Europe/Africa and the
Americas show,even the anomaly at the Equator - the Romanche
trench,indicates the powerful rotational forces beneath your feet.

http://upload.wikimedia.org/wikipedi...che_Trench.jpg

This is one thing genuine dynamicists should actively pursue however
it is likely that the majority will carry their sullen 'definitional'
baggage with them (angular momentum,coriolis, ect, ect) and geology
will experience the same fate as astronomy.The price of tying rotation
directly to an astrological framework is that nobody can really
discuss rotational dynamics and its geological consequences ,the
present mechanism is a thermally driven 'convection cell' conclusion
which causes more problems than it solves and has no association with
either planetary shape or rotation.

People are naturally in tune with rotation and geology so you resort
to dwelling on the argument against tying rotation to an astrological
framework rather than denouncing the rotational geodynamics behind
crustal geodynamics proposal .

oriel36 quoted Newton:

"For to the earth planetary motions *appear sometimes direct,
sometimes stationary, nay, and sometimes retrograde. But from the sun
they are always seen direct.." Newton

**************

But there is nothing wrong with this statement, it is exactly right.
From the earth we see the planets moving in the same direction
(direct) most of the time, but we see them in retrograde a part of the
time, due to the orbital motions of all involved, just as your
animation shows.

From the sun's vantage point you would never see retrograde, only
direct (normal) motion.

What's so hard to understand about this? Can you reference anyone else
who thinks this is incorrect? I didn't think so...

\Paul

On Jan 29, 6:40*pm, palsing wrote:
oriel36 quoted Newton:



"For to the earth planetary motions *appear sometimes direct,
sometimes stationary, nay, and sometimes retrograde. But from the sun
they are always seen direct.." Newton

**************

But there is nothing wrong with this statement, it is exactly right.
From the earth we see the planets moving in the same direction
(direct) most of the time, but we see them in retrograde a part of the
time, due to the orbital motions of all involved, just as your
animation shows.


That is no animation,that is time actual time lapse footage of the
Earth moving in the same direction as the other planets around central
Sun -

http://apod.nasa.gov/apod/ap011220.html

"In this arrangement, therefore, we discover a marvelous symmetry of
the universe, and an established harmonious linkage between the motion
of the spheres and their size, such as can be found in no other way.
For this permits a not inattentive student to perceive why the forward
and backward arcs appear greater in Jupiter than in Saturn and smaller
than in Mars, and on the other hand greater in Venus than in Mercury.
This reversal in direction appears more frequently in Saturn than in
Jupiter, and also more rarely in Mars and Venus than in Mercury.....
All these phenomena proceed from the same cause, which is in the
earth's motion." Copernicus De Revolutionibus.

The condensed view of orbital motion links in with the fact that daily
rotation,observed from a rotating Earth resolves the apparent motion
of the Sun and the daily cycle hence no other resolution is possible
and certainly not by a hypothetical observer on the Sun.



From the sun's vantage point you would never see retrograde, only
direct (normal) motion.


From the Earth's orbital motion all you are seeing is planetary
motions heading in one direction and no 'frame-hopping' is necessary.I
can see how Newton's view dilutes the main arguments for daily and
orbital motions and manipulates them towards a 'forces' agenda via Ra/
Dec modeling -

"It is indeed a matter of great difficulty to discover, and
effectually to distinguish, the true motion of particular bodies from
the apparent; because the parts of that absolute space, in which those
motions are performed, do by no means come under the observation of
our senses. Yet the thing is not altogether desperate; for we have
some arguments to guide us, partly from the apparent motions, which
are the differences of the true motions; partly from the forces, which
are the causes and effects of the true motion." Principia

People are under no obligation to understand the false approach of
Isaac to the main argument for the Earth's orbital motion between
Venus and Mars but they can see for the first time where his views
diverge from those of Kepler and Galileo.





What's so hard to understand about this? Can you reference anyone else
who thinks this is incorrect? I didn't think so...

\Paul


My business is to find people who have the same perception as
Copernicus,Kepler and Galileo through recognition that the Earth's
motion resolves apparent retrograde and not convincing those that a
'hypothetical observer' on the Sun resolves the apparent motions.If
Galileo is not good enough for you,and you revere the man via his
popularisation of the telescope then nothing will as he outlines the
differences between geocentric and heliocentric astronomies and how
Copernicus resolved the issue through the Earth's motions -

Salviati: "In the Ptolemaic hypotheses there are the diseases, and the
Copernican their cure. . . . With Ptolemy it is necessary to assign to
the celestial bodies contrary movements, and make everything move from
east to west and at the same time from west to east, whereas with
Copernicus all celestial revolutions are in one direction, from west
to east. And what are we to say of the apparent movement of a planet,
so uneven that it not only goes fast at one time and slow at another,
but sometimes stops entirely and even goes backward a long way after
doing so? To save these appearances, Ptolemy introduces vast
epicycles, adapting them one by one to each planet, with certain rules
about incongruous motions -- all of which can be done away with by one
very simple motion of the Earth.


Sagredo: I should like to arrive at a better understanding of how
these stoppings, retrograde motions, and advances, which have always
seemed to me highly improbable, come about in the Copernican system.


Salviati: Sagredo, you will see them come about in such a way that the
theory of this alone ought to be enough to gain assent for the rest of
the doctrine from anyone who is neither stubborn nor unteachable. I
tell you, then, that no change occurs in the movement of Saturn in
thirty years, in that of Jupiter in twelve, that of Mars in two, Venus
in nine months, or in that of Mercury in about eighty days. The annual
movement of the Earth alone, between Mars and Venus, causes all the
apparent irregularities of the five stars named. . . .


[Here Salviati explains Jupiter's motion, then follows with:]


Now what is said here of Jupiter is to be understood of Saturn and
Mars also. In Saturn these retrogressions are somewhat more frequent
than in Jupiter, because its motion is slower than Jupiter's, so that
the Earth overtakes it in a shorter time. In Mars they are rarer, its
motion being faster than that of Jupiter, so that the Earth spends
more time in catching up with it. Next, as to Venus and Mercury, whose
circles are included within that of the Earth, stoppings and
retrograde motions appear in them also, due not to any motion that
really exists in them, but to the annual motion of the Earth. This is
acutely demonstrated by Copernicus . . .


You see, gentlemen, with what ease and simplicity the annual motion --
if made by the Earth -- lends itself to supplying reasons for the
apparent anomalies which are observed in the movements of the five
planets. . . . It removes them all and reduces these movements to
equable and regular motions; and it was Nicholas Copernicus who first
clarified for us the reasons for this marvelous effect." GALILEO

1632, Dialogue Concerning the Two Chief World Systems

So,do you see where Newton got it wrong ?,or rather,do you see where
Copernicus got it right using the motion of the Earth to resolve the
apparent stoppings abd temporary bacward motions of the other
planets ? -

http://apod.nasa.gov/apod/image/0112/JuSa2000_tezel.gif

On Jan 29, 12:24*pm, oriel36 wrote:

"In this arrangement, therefore, we discover a marvelous symmetry of
the universe, and an established harmonious linkage between the motion
of the spheres and their size, such as can be found in no other way.
For this permits a not inattentive student to perceive why the forward
and backward arcs appear greater in Jupiter than in Saturn and smaller
than in Mars, and on the other hand greater in Venus than in Mercury.
This reversal in direction appears more frequently in Saturn than in
Jupiter, and also more rarely in Mars and Venus than in Mercury.....
All these phenomena proceed from the same cause, which is in the
earth's motion." *Copernicus De Revolutionibus.

Salviati: "In the Ptolemaic hypotheses there are the diseases, and the
Copernican their cure. . . . With Ptolemy it is necessary to assign to
the celestial bodies contrary movements, and make everything move from
east to west and at the same time from west to east, whereas with
Copernicus all celestial revolutions are in one direction, from west
to east. And what are we to say of the apparent movement of a planet,
so uneven that it not only goes fast at one time and slow at another,
but sometimes stops entirely and even goes backward a long way after
doing so? To save these appearances, Ptolemy introduces vast
epicycles, adapting them one by one to each planet, with certain rules
about incongruous motions -- all of which can be done away with by one
very simple motion of the Earth.

So,do you see where Newton got it wrong ?,or rather,do you see where
Copernicus got it right using the motion of the Earth to resolve the
apparent stoppings abd temporary bacward motions of the other
planets ? -

Since Copernicus and Galileo note that the planets all move in one
direction around the Sun, and they only appear to us to move backwards
sometimes because the Earth is moving, we do not see that what they
are saying and what Newton is saying is in any way different.

But that is because we do not view "frame-hopping" as an evil to be
avoided. To consider things from one viewpoint or another, whichever
is more convenient for a purpose, is instead a useful tool.

As for his "'forces' agenda", that the planets are natural objects,
moving according to the same laws of mechanics as bodies on Earth,
with gravitation being a force that follows the same law as
electrostatic attraction or repulsion... that is Newton's achievement
and contribution. And we predict the motions of the planets to great
accuracy by *using* this 'forces' perspective; the gravity of Jupiter
and Saturn accounts for the changes of the orbits of Mars and the
Earth over time, and this to a high accuracy.

Determining physical laws for the motions of the heavenly bodies was
an objective that Kepler sought to attain, and so it is unreasonable
to criticize Newton for - what, impiety? - in attaining it.

You might think it reasonable to say that since on the Sun and on
Jupiter, different bands of latitude of their atmospheres rotate at
different rates, the Earth must do this as well. But working from
physical law, rather than assuming that similarities create laws, we
can examine the circumstances of each case. The Earth's rigid crust
produces a baseline for the Earth's atmosphere, which does not exhibit
differential rotation, but instead convection cells, and the viscosity
of the magma beneath the crust makes differential rotation there
impossible as well.

John Savard