I've gathered together some facts and nomenclature for starters, Bonsai:
Essentially, all the planets lie in the same orbital plane as the Earth, called the plane of the ecliptic as shown in the diagram below.
The orbits of much less massive bodies such as Pluto, Eris, asteroids or comets are highly inclined to the plane.
The rotation axis of a planet is never perpendicular to the orbital plane of the planet, but is inclined at an angle, which for the Earth is about 23 degrees. This is known as obliquity.
The Sun's axis of rotation lies at an angle of around 7 degrees to the plane of the ecliptic according to the diagram below.
So, to simplify your question, Bonsai: Does the Sun's rotational axis relate to the obliquity of the Earth and the other planets?
Quick answer: Not that I can presently discover!
It's particularly complicated when you look at Venus whose rotation is retrograde and whose axis is inclined at -2.7 degrees.
As to your query about the causes, all I've got is this: A planet suffers the vagaries of gravitational forces in the solar system. Planets are 'buffeted' on the four-dimensional fabric of spacetime, like balls on a trampoline, modified by the gravity of the other planets, the Sun and other stars.
Best I've found!
Essentially, all the planets lie in the same orbital plane as the Earth, called the plane of the ecliptic as shown in the diagram below.
The orbits of much less massive bodies such as Pluto, Eris, asteroids or comets are highly inclined to the plane.
The rotation axis of a planet is never perpendicular to the orbital plane of the planet, but is inclined at an angle, which for the Earth is about 23 degrees. This is known as obliquity.
The Sun's axis of rotation lies at an angle of around 7 degrees to the plane of the ecliptic according to the diagram below.
So, to simplify your question, Bonsai: Does the Sun's rotational axis relate to the obliquity of the Earth and the other planets?
Quick answer: Not that I can presently discover!
It's particularly complicated when you look at Venus whose rotation is retrograde and whose axis is inclined at -2.7 degrees.
As to your query about the causes, all I've got is this: A planet suffers the vagaries of gravitational forces in the solar system. Planets are 'buffeted' on the four-dimensional fabric of spacetime, like balls on a trampoline, modified by the gravity of the other planets, the Sun and other stars.
Best I've found!
Among the 8 planets more or less on the ecliptic plane the Earth is at an extreme case. Mercury is at the other extreme.
This happened with a pretty low probability.
Can one find some fantastic reasons like: This feature made life possible on Earth. This has to do with dinosaurs extinction.
This happened with a pretty low probability.
Can one find some fantastic reasons like: This feature made life possible on Earth. This has to do with dinosaurs extinction.
Regarding the formation of the asteroid belt which I mentioned earlier: I read in Britannica that the rapid growth of Jupiter apparently prevented the formation of a planet in the gap between Jupiter and Mars via the general scheme of planet formation, i.e., the building up of larger masses by the accretion of smaller ones.
Within this gap remain the thousands of objects that make up the asteroid belt, whose total mass is less than one-third the mass of the Moon.
So there was no catastrophic event that befell a planet that once existed between the orbits of Jupiter and Mars. Just saying to set the record straight!
Within this gap remain the thousands of objects that make up the asteroid belt, whose total mass is less than one-third the mass of the Moon.
So there was no catastrophic event that befell a planet that once existed between the orbits of Jupiter and Mars. Just saying to set the record straight!
In post 4,881 there is a "Side view of solar system".
How come ?
Unless an extrordinary coincidence all 8 orbital planes cannot share the same line intersection.
Sure each orbit plane has some angle with the orbit plane of the Earth. But, one needs a top view showing the intersection lines to fully describe the tilt angles.
Furthermore there is likely moves of these lines. Sort of precessions.
Well, here I am at a totally useless bit of science of the kind I am found of.
How come ?
Unless an extrordinary coincidence all 8 orbital planes cannot share the same line intersection.
Sure each orbit plane has some angle with the orbit plane of the Earth. But, one needs a top view showing the intersection lines to fully describe the tilt angles.
Furthermore there is likely moves of these lines. Sort of precessions.
Well, here I am at a totally useless bit of science of the kind I am found of.
I read that two non-parallel planes always intersect along a line.
The orbital plane of a planet and the plane of the ecliptic do so too, and their intersection is called the "line of nodes".
Tell me more about why all 8 orbital planes cannot share the same intersection.
And there were all those collisions with, and perturbations from, other planets that occurred in the early Solar System.
https://www.centralgalaxy.com/how-did-planets-get-their-axial-tilts/
IIRC Pluto is at 11 degrees. The tilt of the planetary orbital planes is one of the factors discussed in the planet 9 hypothesis, along with the perturbed orbits of the trans Neptunian objects aka TNOs
EDIT: I misread at first, but the tilt to the ecliptic of Pluto is 17 degrees.
Last edited:
Thanks to give us the name "line of nodes".
The ecliptic is by definition the plane of the Earth orbit.
Each of the 7 other planets has its orbit plane intersecting the ecliptic at some line of nodes.
There are 7 line of nodes in the ecliptic.
From a geometry point of view these 7 could be the same one, but I doubt it.
How come a unique line of nodes could be ? Some reason in the creation of the solar system ! Some synchronisation in the evolution of the solar system !
I do not see such mecanisms.
I rather think, it is a random setting and not even stable over ages.
Astronomers do know; Line of nodes is a must knowledge in predicting satellites positions. Positions known with an astronomic accuracy.
I think a clearer picture comes up if you take the tilt of the planetary orbital planes wrt the Sun’s axis of spin, rather than the ecliptic. In an ideal situation, all the planets would orbit in a plane close to perpendicular to the Sun’s axis of rotation. The question then is why are the orbital planes tilted in the way they are and secondly, why are planets axis of rotation tilted?
Questions, questions . . .
Questions, questions . . .
Last edited:
My legendary googling skills have drawn a blank on why the Sun is inclined at 7 degrees to the ecliptic.
The reason may simply be down to the chaotic nature of the Solar System and so is a case of "it is what it is".
What I do know is that we can't understand Solar System mechanics without referring to orbital angular momentum:
The giant planets contribute 98% of the Solar System's angular momentum.
All four of these planets are inclined at practically the same angle to the Sun's equator - Jupiter 6.1, Saturn 5.5, Uranus 6.5, Neptune, 6.4 degrees.
So, for almost all purposes, the plane defined by the giant planets' orbits alone dictates the mechanics of the Solar System.
I think I shall leave it at that!
I struggle to understand why the orbital planes of any of the larger planets would not be very close to perpendicular to the Sun’s rotation axis but let’s assume it’s within a certain band. But then, why would all 4 be so closely aligned in the same direction? Its almost as if they were all aligned and then something came along and tipped either the Sun on its axis (unlikely), or hung around long enough to tip the orbital planes of the planets wrt the Sun’s axis of rotation.
(I note there are two things going on here- the axial tilt of the planets wrt the Sun’s, and the orbital plane tilt wrt the Sun”’s axis of rotation - both intriguing).
(I note there are two things going on here- the axial tilt of the planets wrt the Sun’s, and the orbital plane tilt wrt the Sun”’s axis of rotation - both intriguing).
Interesting article here that points out that multiple distant objects that are physically close to each other exhibit large disparities in red shift.
https://phys.org/news/2024-09-quantized-redshift-big-hypothesis.html
What is going on? JWST appears to have thrown the whole paradigm of the early universe development into disarray.
https://phys.org/news/2024-09-quantized-redshift-big-hypothesis.html
What is going on? JWST appears to have thrown the whole paradigm of the early universe development into disarray.
It's those "alternative cosmologists" who do not agree with the concept of the expansion of the universe!
Enter the physics of "quantised redshift".
Quote: "The Hoyle–Narlikar variable mass hypothesis provides a framework in which quasars are ejected from galactic nuclei, starting with low mass and high redshift, extracting energy from the surrounding system, and over time, increasing in mass and decreasing in redshift, with redshift being related to mass rather than distance."
I shall have to sleep on that!
I've been investigating how the Near-Infrared Camera (NIRCam) on the JWST is used to measure the redshift of a galaxy.
NIRCam uses multiple filters to collect a galaxy’s light in several different colour or wavelength steps to determine the "photometric redshift".
Photometric redshift of a galaxy can have a broad probability distribution, but this is improving as the photometry is measured in ever finer wavelength steps.
As the photometry improves, the JWST findings are being revised. For example:
In July 2022, teams used NIRCam images to identify two galaxies with photometric redshifts greater than 11 (when the Universe was less than 420 million years old.)
However, In February 2023, the teams followed up their high-redshift candidates and used NIRCam to measure precise, spectroscopic redshifts. One candidate (Maisie’s Galaxy) has been confirmed to be at redshift 11.4 (when the universe was 390 million years old), while the second candidate was discovered to actually be at a lower redshift of 4.9 (when the universe was 1.2 billion years old.)
I read it here: https://scitechdaily.com/redshift-riddles-decoding-distance-with-space-telescopes/
NIRCam uses multiple filters to collect a galaxy’s light in several different colour or wavelength steps to determine the "photometric redshift".
Photometric redshift of a galaxy can have a broad probability distribution, but this is improving as the photometry is measured in ever finer wavelength steps.
As the photometry improves, the JWST findings are being revised. For example:
In July 2022, teams used NIRCam images to identify two galaxies with photometric redshifts greater than 11 (when the Universe was less than 420 million years old.)
However, In February 2023, the teams followed up their high-redshift candidates and used NIRCam to measure precise, spectroscopic redshifts. One candidate (Maisie’s Galaxy) has been confirmed to be at redshift 11.4 (when the universe was 390 million years old), while the second candidate was discovered to actually be at a lower redshift of 4.9 (when the universe was 1.2 billion years old.)
I read it here: https://scitechdaily.com/redshift-riddles-decoding-distance-with-space-telescopes/
Your link spoke of "two quasars resting on a filament that connects two galaxies - all four objects have different redshifts from one another".
Note that the above observation was made 20 years ago and redshift measurement techniques have certainly improved since then.
The other observation mentioned in the link was "an apparent physical association of quasars and galaxies but with different redshifts" and this was made 58 years ago.
Do you see where I am going with this?
Note that the above observation was made 20 years ago and redshift measurement techniques have certainly improved since then.
The other observation mentioned in the link was "an apparent physical association of quasars and galaxies but with different redshifts" and this was made 58 years ago.
Do you see where I am going with this?
That one I believe uses an improvement of the old way. A prism splits the light. That projected onto a ccd so pixel position reads wavelength directly. I also think it can occult bright objects.