Why is the earth's axis tilted?
Post Reply
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
07-10-2014, 06:57 PM
RE: Why is the earth's axis tilted?
(07-10-2014 04:22 PM)cjlr Wrote:  The angular momentum imparted by collisions is not nearly enough to significantly alter the overall rotation of a planet.

Without going back to check for myself, it sounds like the quote you've pulled relates more to the eccentricity of the Earth's orbit, and not its axial tilt (it's spin motion and it's orbital motion being, for many purposes, essentially decoupled).

It would be angular momentum colliding with smaller planets back then. Remember this is in the formation stage of the solar system.

"If you cannot explain it simply, you don't understand it enough" -Albert Einstein
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 08:54 PM
RE: Why is the earth's axis tilted?
(07-10-2014 04:56 PM)smileXsmileXsmile Wrote:  
(07-10-2014 04:22 PM)cjlr Wrote:  The angular momentum imparted by collisions is not nearly enough to significantly alter the overall rotation of a planet.

Without going back to check for myself, it sounds like the quote you've pulled relates more to the eccentricity of the Earth's orbit, and not its axial tilt (it's spin motion and it's orbital motion being, for many purposes, essentially decoupled).

eccentricity in two dimensions wouldn't be a factor, but the slight angle of that eccentricity, in the third dimension might. All three planets must have their own somewhat angled eccentric orbit in the third dimension. There's also the factor of where Jupiter, Earth, and Venus lie on the z-axis.

But then again, isn't the earth's 23% tilt too extreme for venus, earth, and jupiter being "pretty much" being on the same (3 dimensional) plane? It might not be I don't know.


I'm dumbfounded. Can you, or anyone explain?

Earth's orbital eccentricity refers to the deviation from circularity of its orbital path. This the aspect most easily influenced by other masses.

The orbital inclination is the angle between Earth's orbit and the average solar plane.

The orbital obliqueness is the axial tilt.

It's quite possible - and, indeed, far more likely - that coalescing masses in the early solar system would acquire irregular paths.

... this is my signature!
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:01 PM
RE: Why is the earth's axis tilted?
(07-10-2014 06:42 PM)smileXsmileXsmile Wrote:  I'm thinking it must have been impact theory because all of the planets are on the same 3 dimensional plane. It could've been impact theory during formation or impact theory after formation, but in my mind it would have to be impact theory. If axis tilt was based on gravity all of the planets would have a close to zero degree tilt from the start. I'm thinking Uranus got hit by a comet or something ...even though its gas ..idk.

The impact theory would be further plausible, because as we know, when a solar system forms, the cloud of debris gets flattens into a rotating disk via the nature of gravity, thus because of this flattened disk of the debris, i the maximum tilt wasn't able to achieve over 26° because all of the impacts were coming from within the rotating flattened disk of debris. I hope that made since.

wow so the show cosmos is wrong? Agree/Disagree?

They are not on the same plane. They all possess some relative inclination. The planets are all approximately on the same plane (minor planets and planetoids are not!) because of the early solar system's behaviour.

That sort of planetary formation is a chaotic process; even a single planet is very unlikely to possess an axial tilt of exactly zero degrees.

I don't think collision can explain much of what we observe, but the perturbative influence of other early centres of mass would certainly influence the moments of a forming body.

Z-axis isn't really the proper paradigm; orbital mechanics make far more sense in spherical coordinates!

... this is my signature!
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:03 PM
RE: Why is the earth's axis tilted?
Is it earth's magnetic field or earths orbit/rotation that defines its access?
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:04 PM
RE: Why is the earth's axis tilted?
(07-10-2014 08:54 PM)cjlr Wrote:  
(07-10-2014 04:56 PM)smileXsmileXsmile Wrote:  eccentricity in two dimensions wouldn't be a factor, but the slight angle of that eccentricity, in the third dimension might. All three planets must have their own somewhat angled eccentric orbit in the third dimension. There's also the factor of where Jupiter, Earth, and Venus lie on the z-axis.

But then again, isn't the earth's 23% tilt too extreme for venus, earth, and jupiter being "pretty much" being on the same (3 dimensional) plane? It might not be I don't know.


I'm dumbfounded. Can you, or anyone explain?

Earth's orbital eccentricity refers to the deviation from circularity of its orbital path. This the aspect most easily influenced by other masses.

The orbital inclination is the angle between Earth's orbit and the average solar plane.

The orbital obliqueness is the axial tilt.

It's quite possible - and, indeed, far more likely - that coalescing masses in the early solar system would acquire irregular paths.

The moving gravitational fields of all the bodies in the solar system interact with every body in the solar system and continually change each other's orbits. It is complicated and not generally solvable.

This is the n-body problem and is computationally intractable (or was he last time I checked).

Skepticism is not a position; it is an approach to claims.
Science is not a subject, but a method.
[Image: flagstiny%206.gif]
Visit this user's website Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:06 PM
RE: Why is the earth's axis tilted?
(07-10-2014 09:03 PM)Michael_Tadlock Wrote:  Is it earth's magnetic field or earths orbit/rotation that defines its access?

Axis refers to axis of rotation. Not every rotating body has a magnetic field.

Skepticism is not a position; it is an approach to claims.
Science is not a subject, but a method.
[Image: flagstiny%206.gif]
Visit this user's website Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:10 PM
RE: Why is the earth's axis tilted?
(07-10-2014 09:04 PM)Chas Wrote:  
(07-10-2014 08:54 PM)cjlr Wrote:  Earth's orbital eccentricity refers to the deviation from circularity of its orbital path. This the aspect most easily influenced by other masses.

The orbital inclination is the angle between Earth's orbit and the average solar plane.

The orbital obliqueness is the axial tilt.

It's quite possible - and, indeed, far more likely - that coalescing masses in the early solar system would acquire irregular paths.

The moving gravitational fields of all the bodies in the solar system interact with every body in the solar system and continually change each other's orbits. It is complicated and not generally solvable.

Yes, of course. Although, as I mentioned, we can in many cases consider the orbital and rotational behaviour separately.

(07-10-2014 09:04 PM)Chas Wrote:  This is the n-body problem and is computationally intractable (or was he last time I checked).

Worse than that; in the early accretion disk it's functionally an n-body problem in the continuum limit! But yeah. It's a chaotic system. Not only is it provably analytically insoluble, but it's prohibitively complicated to treat numerically.

... this is my signature!
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 09:12 PM
RE: Why is the earth's axis tilted?
(07-10-2014 09:06 PM)Chas Wrote:  
(07-10-2014 09:03 PM)Michael_Tadlock Wrote:  Is it earth's magnetic field or earths orbit/rotation that defines its access?

Axis refers to axis of rotation. Not every rotating body has a magnetic field.

No, but a rotating body with a magnetic moment possesses a magnetic field - so in that sense planetary magnetic fields are defined by the axis of rotation.

Although as the magnetically relevant bodies are generally non-rigid and non-uniform they're even wobblier than the rotation axes themselves...

... this is my signature!
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 10:32 PM (This post was last modified: 07-10-2014 11:08 PM by smileXsmileXsmile.)
RE: Why is the earth's axis tilted?
(07-10-2014 08:54 PM)cjlr Wrote:  Earth's orbital eccentricity refers to the deviation from circularity of its orbital path. This the aspect most easily influenced by other masses.

The orbital inclination is the angle between Earth's orbit and the average solar plane.

The orbital obliqueness is the axial tilt.

It's quite possible - and, indeed, far more likely - that coalescing masses in the early solar system would acquire irregular paths.

It's tough talking without a visual aid. This is not the ideal image but should help.

[Image: planets.jpg]

Anyway... so if gravity is the result of Earth's axis tilt, as some point, Jupiter's inner part of its inclined eccentricity must have been above the Earth; and therefore Jupiter's outer part of its inclined eccentricity must have been below the Earth.

and Venus must have been the opposite: Venus' inner part of its inclined eccentricity must have been below the Earth; and therefore Venus' outer part of its inclined eccentricity must have been above the Earth.

.....at least during formation, until the planets held too much gravity to be easily affected by things, possibly longer. It also likely that all planets did not grow at exactly the same rate thus influencing gravitational pulls. Then, I would image the disk of planets to further flatten due to the nature of gravity to give us what we have today.

We on the same page? What a mind fuck lol

If we're on the same page, wouldn't it be logical to think, with enough time, that all planets' axises will straighten out even further (closer to zero) due to centrifugal force pushing more mass to the outer edges. On the other hand, centrifugal force could be a minuscule variable.

but check out this: http://astro.unl.edu/naap/pos/animations/kepler.html , or any planet eccentricity chart, the planets don't look very eccentric at all, at least today they don't. hmmm. like i said, but that's today's chart
Find all posts by this user
Like Post Quote this message in a reply
07-10-2014, 10:59 PM (This post was last modified: 07-10-2014 11:02 PM by Shadow Fox.)
RE: Why is the earth's axis tilted?
I have a theory that Uranus rotation is normal. It is the rest of the planets that are spinning the wrong direction.


My Youtube channel if anyone is interested.
https://www.youtube.com/channel/UCEkRdbq...rLEz-0jEHQ
Find all posts by this user
Like Post Quote this message in a reply
Post Reply
Forum Jump: