Shape of planetary orbital paths

[matterdoc]

By simple mechanics, no free macro body can orbit around another moving macro body in any type of closed geometrical path. Yet;

(1). Knowing sun is a moving macro body, why do we perpetuate circular/elliptical planetary orbits around the sun, in all text books and other literature?

(2). Knowing earth is a moving macro body, why do we perpetuate circular/elliptical orbital path for moon around earth, in all text books and other literature?

Planetary laws are derived from relative positions of few planets about a static sun. They are good enough to predict relative positions (and cyclic phenomena related to relative positions) of macro bodies in a planetary system. Although they do not give real parameters of concerned macro bodies, why do we use planetary laws to find real parameters?.

Kindly see; http://vixra.org/abs/1311.0018

Nainan

[Strange]

They are good enough to predict relative positions (and cyclic phenomena related to relative positions) of macro bodies in a planetary system.

 

And that is exactly what they are used for. As all motion is relative, it is entirely reasonable to choose a Sun-centered coordinate system (or Earth-centered) when appropriate.

 

 

Kindly see; http://vixra.org/abs/1311.0018

 

Er, no thanks. Occasionally vixra papers are funny, but they are usually just very, very sad.

[swansont]

 

By simple mechanics, no free macro body can orbit around another moving macro body in any type of closed geometrical path.

 

 

Excuse me?

[Nicholas Kang]

Which mechanics? Never heard of both newtonian(classical) and quantum mechanics stating such law.

[Greg H.]

 

By simple mechanics, no free macro body can orbit around another moving macro body in any type of closed geometrical path.

 

I'll have to echo Swansont here. What?

[Strange]

Having skimmed the vixra paper (why do I do these things) it appears to be an extended and pointless statement of the obvious.

 

Apparently, if you view an orbit from a moving frame of reference, it no longer looks like a circle or an ellipse but a wiggly line. Who knew.

Edited August 13, 2014 by Strange

[Nicholas Kang]

Having skimmed the vixra paper (why do I do these things) it appears to be an extended and pointless statement of the obvious.

 

Apparently, if you view an orbit from a moving frame of reference, it no longer looks like a circle or an ellipse but a wiggly line. Who knew.

 

Why wiggly line?

[Strange]

 

Why wiggly line?

 

For example, consider the orbit of the moon when seen from the frame of reference of the sun:

 

If the Earth moved faster, then the orbit just becomes a wiggle:

[Nicholas Kang]

Ok, I understand 50%. i can roughly get the idea. But to imagine I am a Sun and seeing the moon moving in a wavy string-like orbit is hardly possible to me. Can you explain how can the Sun "sees" the moon orbiting in a string-like motion, I would have thought it is a straight line. Imagine I am the Sun, the moon passes by in front of me, it moves harmonically with steady motion.

[Strange]

Well, I wasn't really saying what the Sun sees but just what you see if you consider the Sun to be stationary instead of our normal view (for the Moon's orbit) of the Earth being stationary.

 

If you were on the sun, you would see the moon going round you but getting closer and further away as it went round the Earth.

[Nicholas Kang]

Ok, I know why now. I have forgotten the Earth. Thanks. I got it, fully 100%

Good drawing too.

[Strange]

Good drawing too.

 

Not mine! Found them online.

[Nicholas Kang]

Ok. Good and fast searching.

[Strange]

Although they do not give real parameters of concerned macro bodies, why do we use planetary laws to find real parameters?

 

What do you mean by "real parameters"?

[Greg H.]

 

For example, consider the orbit of the moon when seen from the frame of reference of the sun:

*snipped the images for brevity*

 

Oh, well, yeah that makes sense - but haven't we more or less known this for a long time?

[Strange]

 

Oh, well, yeah that makes sense - but haven't we more or less known this for a long time?

 

You would think so. But apparently the OP considers it a novel breakthrough.

[Nicholas Kang]

What does OP means? What does OP stands for?

[Strange]

What does OP means? What does OP stands for?

 

Orignal Poster (or Original Post). Often used to refer the originator of a thread, or their first post.

[swansont]

 

For example, consider the orbit of the moon when seen from the frame of reference of the sun:

 

If the Earth moved faster, then the orbit just becomes a wiggle:

 

It's not even this, because the OP mentions a two-body system, and simple mechanics. So I'd like to know why we are prevented from analyzing the system in the center-of-mass frame — that seems like the simplest mechanics — and how we don't get closed orbits.

[Janus]

For example, consider the orbit of the moon when seen from the frame of reference of the sun:

 

If the Earth moved faster, then the orbit just becomes a wiggle:

I just want to point out that the Moon's heliocentric path in reality is like the second drawing and not the first. (and if drawn to scale would be concave to the Sun at all points.)

Having skimmed the vixra paper (why do I do these things) it appears to be an extended and pointless statement of the obvious.

 

Apparently, if you view an orbit from a moving frame of reference, it no longer looks like a circle or an ellipse but a wiggly line. Who knew.

It always amazes me that when some people "discover" things like this for themselves, they tend to treat it as some great revelation that they have uncovered that everyone else has missed.

[Ophiolite]

 

By simple mechanics, no free macro body can orbit around another moving macro body in any type of closed geometrical path.

 

I am a simple minded geologist, though my friends say I am just simple minded. Could you explain, using simple mechanics, why what you assert is true?

[matterdoc]

@strange @Janus

By real parameters, I meant parameters of real physical actions. Apparent parameters are those observed with respect to references. For example; According to present concept, earth moves at (almost) constant and unidirectional angular speed around sun. This is an apparent parameter as is observed from sun. However, an observer from outside solar system would see earth’s real angular motion (parameter) as of constantly varying magnitude and changing directions every half orbit about moving sun’s path (wavy).

I have not made a new discovery. All I meant was ‘having prior knowledge of non-circular orbital motion, why do we perpetuate circular planetary orbits in all text books and other literature’. Have you come across any text book or other literature that qualifies circular orbital path as apparent only with respect to a static sun? Even Kepler’s planetary laws unambiguously state that planetary orbit is elliptical, with sun at one of its focus.

Kindly note that Kepler’s planetary laws were derived from relative positions of few planets with respect to sun, as observed from earth. He has conveniently avoided parameters of moon, which was much easier to observe from earth. Having considered earth as a moving macro body, moon’s orbital motion would not suit his planetary laws, which were based on static central body. Although we have better information, we use and perpetuate same planetary laws for all cosmic bodies, including moon.

You could avoid intended ridicule.

 

@ophiolite

Kindly see http://vixra.org/abs/1311.0018

Regards,

Nainan

[swansont]

 

All I meant was ‘having prior knowledge of non-circular orbital motion, why do we perpetuate circular planetary orbits in all text books and other literature’.

 

 

Because we don't? You learn circular motion because it's simple and a necessary step in mechanics, and you can use it as an approximation, but it's not like elliptical orbits are kept secret. A google book search for "physics elliptical orbit" yields more than 38,000 results. How is that "perpetuat[ing] circular planetary orbits in all text books"?

[Strange]

However, an observer from outside solar system would see earth’s real angular motion (parameter) as of constantly varying magnitude and changing directions every half orbit about moving sun’s path (wavy)

 

Well, that depends where that observer is and how they are moving with respect to the sun. Their observations will still be "apparent". Or equally "real".

 

Are you talking about the Sun's movement around the galaxy?

 

 

You could avoid intended ridicule.

 

I tried. But when someone says something as silly as this ...

[Ophiolite]

 

@ophiolite

Kindly see http://vixra.org/abs/1311.0018

Regards,

Nainan

 

So, in short, you think it is significant that you have noticed the simplifications, or conveniences of calculation, made in describing orbits and believe that others have failed to recognise these simplifications, or conveniences of calculation. It is interesting that the bloody obvious is so bloody obvious to the bulk of the scientifically literate that they feel no need to state the bloody obvious at every turn and certainly not in a paper that purports to assert that the bloody obvious has not been previously recognised. I appreciate your help in clarifying this for me and apologise for not recognising, from the outset, that the error of thinking you were making was bloody obvious.