Coordinate Systems

There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?
Which coordinate system is usually used in astronomy?
For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

"q-bit" escreveu na mensagem
...
There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?

Rotating bodies require a rotating frame of reference.
In 3D you need a set of three orthogonal rotating axis,
called the "principal axis".

Which coordinate system is usually used in astronomy?

A fixed orthogonal coordinate system, fixed on Earth I believe.

For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

You need a coordinate transformation between the rotating
coordinate system and the fixed coordinate system.
You also need Euler angles to express your equations.
Summarising, you are screwed.
The actual Physics took a short cut somewhere. It was
stated that rotating coordinate systems are not inertial,
it was assumed the "equivalence principle" and the
global confusion is all around.

q-bit wrote:

There are unfortunately many coordinate systems,]

Try doing H2+ outside confocal ellipsoidal coordinates.
Multiplicities of coordinate systems are in common use because a wise
choice cuts through all the goo dribble of fitting square pegs into
round holes. Crystal unit cells have their own internal coordinates
(x/a,y/b,z/c) with angles alpha,beta, gamma arbitrary.

Idiot.

and I'm new to this topic.

You aren't a virgin in whorehouse. You are a capon in a henhouse.

On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?

General Relativity is covariant - no coordinate background.

Which coordinate system is usually used in astronomy?

Look up the directions to Messier Object 31.

For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

Hey stupid, you've already chosen a coordinate system - an awful one
for rotational symmetry. Ask NASA what they use for calculating
Hohmann transfers.

"Tired of calculating so many epicycles? That's why we've introduced
the Ronco Equant Point!

The Ronco Equant Point is a pointless mathematical abstraction that
gives you that perfect Renaissance instrumentalist astronomical
result! Up to 200% more accurate than the other leading brand of
Ptolemaic system, the Ronco Equant point will actually reduce the
number of epicycles within 20 minutes - or your money back!"


--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2

"Uncle Al" wrote in message
...


Hey Ewe!


--
'we establish by definition that the "time" required by
light to travel from A to B equals the "time" it requires
to travel from B to A' because I SAY SO and you have to
agree because I'm the great genius, STOOOPID, don't you
dare question it. -- Rabbi Albert Einstein

http://www.androcles01.pwp.blueyonde...rt/tAB=tBA.gif

"What can be asserted without evidence can also be dismissed without
evidence." -- Uncle Stooopid.


"Counterfactual assumptions yield nonsense.
If such a thing were actually observed, reliably and reproducibly, then
relativity would immediately need a major overhaul if not a complete
replacement." -- Humpty Roberts.

Rabbi Albert Einstein in 1895 failed an examination that would
have allowed him to study for a diploma as an electrical engineer
at the Eidgenössische Technische Hochschule in Zurich
(couldn't even pass the SATs).


****head.

"q-bit" wrote in message
...
There are unfortunately many coordinate systems,
and I'm new to this topic.

Well folks around here know me so well that if I didn't have a web page for
it they'd think something was wrong with me. LOL!!

See - http://www.geocities.com/physics_wor...ord_system.htm

There are three common coordinate systems used in physics a great deal. They
are

(1) Cartesian Coordinates
(2) Polar Coordinates
(3) Spherical Coordinates

The last two are outlined in the web page above. You're probably already
familiar with Cartesian coordinates.

Pete

On Mon, 27 Aug 2007 20:47:58 +0200, "q-bit"
wrote:

There are unfortunately many coordinate systems,
and I'm new to this topic.

Thus validating my belief that you never took classical mechanics and
that your education in physics is limited to what you learned in high
school.

On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?

Parabolic coordinates.

Which coordinate system is usually used in astronomy?
For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

If you have to ask questions like this, you might want to consider
getting a textbook.

On Aug 28, 4:47 am, "q-bit" wrote:
There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?

Use the coordinate-free approach of Geometric Algebra. That's the
direction 3D computer graphics is going.

On Aug 28, 6:47 am, "q-bit" wrote:
There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?
Which coordinate system is usually used in astronomy?
For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

There are at least 3 for a Satellite.

The celestial co-ordinates from earth (referenced to a star)
The Satellite co-ordinates
another one for it moving which gives us roll-pitch etc

Look for papers on Satellite control systems.

"HardySpicer" wrote in message
ps.com...
On Aug 28, 6:47 am, "q-bit" wrote:
There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?
Which coordinate system is usually used in astronomy?
For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.


(1) Cartesian Coordinates
(2) Polar Coordinates
(3) Spherical Coordinates
(4) Cylindrical


I also believe that there is another oen that makes sense - a "scalar
coordinate system".




In the following, all of the E(n) are probabilistic, expected values.



E(1) = expected value of length segment
|---------------------------------------------------------|


E(1) E(2)
|---------------------------|------------------------------|


E(1) E(2) E(3)
|-----------------|--------------------|--------------------|


E(1) E(2) E(3) E(4)
|------------|--------------|---------------|----------------|


E(1) E(2) E(3) E(4) E(5)
|---------|----------|------------|-------------|-------------|


By hypothesis: for all scales m,n


__m__ ___n__
\ \ \ \
Length = \ E(a) = \ E(b)
/ /
/______/ /______/
a=1 b=1


In other words, the expected value of length should be the same on all
scales for a given piece of length. The summation above is a statement which
explains conservation of energy in terms of dimension.



One can introduce a scalar coordinate system something like this :



E(1,1)
|---------------------------------------------------------|


E(2,1) E(2,2)
|---------------------------|------------------------------|


E(3,1) E(3,2) E(3,3)
|-----------------|--------------------|--------------------|


E(4,1) E(4,2) E(4,3) E(43,4)
|------------|--------------|---------------|----------------|


E(5,1) E(5,2) E(5,3) E(5,4) E(5,5)
|---------|----------|------------|-------------|-------------|


Expanding on this idea a little, our "Scalar Coordinate System" can be
written as follows :


E(0,0)
|---------------------------------------------------------|


E(1,-1) E(1,1)
|---------------------------|------------------------------|


E(2,-2) E(2,-1) E(2,1) E(2,2)
|-------------|--------------|---------------|----------------|


E(3,-3) E(3,-2) E(3,-1) E(3,1) E(3,2) E(3,3)
|--------|---------|----------|----------|----------|-----------|


......etc etc.



Example:


Sun E(0,0)
Earth
|---------------------------------------------------------|


Sun E(1,-1) E(1,1)
Earth
|---------------------------|------------------------------|


E(2,-2) E(2,-1) E(2,1) E(2,2)
|-------------|--------------|---------------|----------------|


E(3,-3) E(3,-2) E(3,-1) E(3,1) E(3,2) E(3,3)
|--------|---------|----------|----------|----------|-----------|


In the above example, we expect that:
E(3,-3) E(3,-2) E(3,-1) E(3,1) E(3,2) E(3,3)

but also that

E(3,-3) + E(3,-2) + E(3,-1) + E(3,1) + E(3,2) + E(3,3) = E(0,0)



YEAH - REALLY !!!!!!!!




http://sciphysicsopenmanuscript.blogspot.com/

On Aug 27, 1:47 pm, "q-bit" wrote:
There are unfortunately many coordinate systems,
and I'm new to this topic.
On which coordinate system should I concentrate
myself for surface and orbit research for rotating
celestial objects in 3D space?
Which coordinate system is usually used in astronomy?
For example for moving from point (x,y,z) to point (x',y',z'),
and calculating the distance etc.

There is no physically favorable choice of coordinate systems, only a
choice based on computational convenience. Which you choose depends on
which computations you want to make, and that often switches in the
middle of what you're doing, and so you also need to be able to switch
from from coordinate system to another with ease.

This is one of those skills that only comes from hard practice, like
playing scales for a musician. There is no short cut.

PD