## Inventions and Deceptions – Barycentric Orbits

Barycentric Orbits are presented by Wikipedia as the scientifically correct mechanism that controls celestial orbits:

The center of mass plays an important role in astronomy and astrophysics, where it is commonly referred to as the barycenter. The barycenter is the point between two objects where they balance each other; it is the center of mass where two or more celestial bodies orbit each other. When a moon orbits a planet, or a planet orbits a star, both bodies are actually orbiting around a point that lies away from the center of the primary (larger) body.

For example, the Moon does not orbit the exact center of the Earth, but a point on a line between the center of the Earth and the Moon, approximately 1,710 km (1062 miles) below the surface of the Earth, where their respective masses balance. This is the point about which the Earth and Moon orbit as they travel around the Sun.

http://en.wikipedia.org/wiki/Barycentre

The Moon makes a complete orbit around the Earth with respect to the fixed stars about once every 27.3 days (its sidereal period). However, since the Earth is moving in its orbit about the Sun at the same time, it takes slightly longer for the Moon to show the same phase to Earth, which is about 29.5 days (its synodic period).

Unlike most satellites of other planets, the Moon orbits nearer the ecliptic plane than to the planet’s equatorial plane. The Moon’s orbit is subtly perturbed by the Sun and Earth in many small, complex and interacting ways. For example, the plane of the Moon’s orbital motion gradually rotates, which affects other aspects of lunar motion. These follow-on effects are mathematically described by Cassini’s laws.

http://en.wikipedia.org/wiki/Moon#Orbit

The Wikipedia wording is very interesting to say the least:

the Moon does not orbit the exact center of the Earth, but a point on a line between the center of the Earth and the Moon, approximately 1,710 km (1062 miles) below the surface of the Earth, where their respective masses balance. This is the point about which the Earth and Moon orbit as they travel around the Sun.

Firstly, the point [barycentre] that is approximately 1,710 kilometres below the surface of the Earth is not really a point at all. It continually moves up and down [over a range of 610 kilometres] because at Maximum Perigee the barycentre is 2,039 kilometres below surface while at Maximum Apogee the barycentre is 1,429 kilometres below the surface.

The point [barycentre] is also continually moving longitudinally within the Earth as the Earth performs its daily axial rotation and the Moon performs its regular 360 degree observed orbit around the Earth. The point [barycentre] is additionally continually moving latitudinally due to the 5.14 degree inclination of the Lunar orbit and the Earth 23.44 axial tilt.

Therefore, the point [barycentre] is continually moving through all three dimensions and cannot seriously be considered a pivot point about which both the Earth and the Moon orbit.

Curiously, Wikipedia [in an article about Barycentric Coordinates] indicates that the Earth really only “wobbles” [in an unspecified manner] and does not actually orbit the barycentre!

When the barycenter is located within the more massive body, that body will appear to “wobble” rather than following a discernible orbit.

http://en.wikipedia.org/wiki/Barycentric_coordinates_%28astronomy%29

The non-specific Earth “wobble” seems to be the point where Wikipedia becomes evasive. The “wobble” can be interpreted [as in their animation] as the Earth rotating around an internal pivot point [the barycentre]. However, this interpretation seems unrealistic because it would cause a centrifugal tidal bulge on the side of the Earth most distant from the barycentre. I am not aware of any barycentric tidal bulge.

The barycentric perception also implies that the Earth’s dense core is significantly out of alignment with the Earth’s barycentric pivot point. The pivot point is located 1,429 kilometres below the surface in the Earth’s ductile mantle and it seems very doubtful that the other 11,313 kilometres [worth of mass including the dense core] could pivot around the barycentre without significant deformation [or disintegration] of the spheroid Earth.

Image credit: Wikipedia http://en.wikipedia.org/wiki/Earth_core

Secondly, the concept of an Earth-Moon barycentre is fundamentally flawed because the underlying barycentre formula derives from the familiar terrestrial machine called a lever which consists of a beam [rigid rod] that pivots around a fixed hinge [fulcrum] that is resting upon firm ground [or a solid surface].

Image credit: Wikipedia http://en.wikipedia.org/wiki/File:Palanca-ejemplo.jpg

Applying these principles to the Earth and the Moon highlights several problems:
1) There is no rigid bar or beam in space upon which the planets can rest.
2) There is no hinge or fulcrum resting on solid ground.
3) Gravitation between the Earth and Moon is a horizontal vector [not vertical].

Image credit: Wikipedia http://en.wikipedia.org/wiki/File:Moon_Earth_Comparison.png

Overall, the Earth-Month barycentric orbital concept is fundamentally flawed especially as the Earth does not orbit the barycentre [it just “wobbles” in some way] and the pivot point is not fixed [in wanders about in all three special dimensions].

The [claimed] barycentric “wobble” of the Earth can not be separated from other factors that generate “wobble”. For example, an uneven mass distribution would also cause the Earth to “wobble” during its daily axial rotation. Additionally, it is impossible to perform a control experiment [“with the Moon” and “without the Moon”] that demonstrates the barycentric Earth “wobble”.

Similarly, the [claimed] barycentric “wobble” of the Sun around the solar system barycentre cannot be separated from other factors that generate “wobble”.

Additionally, the [claimed] barycentric “wobble” of the Sun [around the solar system barycentre] does not apparently have any impact on the distance between the Earth and the Sun because any Earth “wobble” is apparently attributed to perturbations by Jupiter and Venus.

The barycentric theory is non-scientific because it does not provide any specific [observable] verifiable predictions.

Gallery | This entry was posted in Astrophysics, Earth, Gravity, Inventions and Deceptions, Moon, Science, Solar System. Bookmark the permalink.

### 14 Responses to Inventions and Deceptions – Barycentric Orbits

1. tim timmons says:

Could you please explain what the barycentric theory is, who came up with it, and where I can find more information about it. Thank you.

The theory is associated with the “Centre of Gravity” concept
see: http://en.wikipedia.org/wiki/Barycentre
Unfortunately, I haven’t discovered how this concept morphed into the barycentric theory. It seems to be a very “grey area”.
If I discover more then I will update this post.
Tim

after so many explantions from books and examples from web, I didn’t understand the barycenter. Probably it is something more to understand then just a simple momentum conservation rule. From your artcle I culd understand, that the berycenter does not have simple explanation. Is it realy earth orbiting barycenter in 29 days? When anybody can prove that, then the momentum conservation rule is correct but it is working without rod, it is unvisible rope called gravity. Newton also tried to understand this force on distance, but finaly gave up. Einstan told that there is not any gravity force but just curved space. As long we can make correct prrdiction from the rules of phisic we can use them until we get better one, even we do not have explanation why is it so. And Kepler and Newtan laws are stil in use today. Einsten is maybe great, but I don’t understand him, and don’t like the rule of limiting the speed to speed of light.

Reply: There are many aspects of modern science I don’t understand and many aspects which I think are wrong… I especially don’t like the invention of the “Space-Time” dimension by Einstein… so you are not alone… I hope you find some of my ideas and explanations helpful.

3. tallbloke says:

Hi Tim, it’s great you’ve posted this, as it gives me the opportunity to formally address your points.

“Barycentric Orbits are presented by Wikipedia as the scientifically correct mechanism that controls celestial orbits:”

Within the classical framework, mass, momentum and gravity control the orbits, the barycentre is a logical outcome of the resolution of the forces, not ‘a mechanism’. If you want a discussion in some other framework you’ll have to provide some definitions.

“Therefore, the point [barycentre] is continually moving through all three dimensions and cannot seriously be considered a pivot point about which both the Earth and the Moon orbit.”

Moving with respect to what? It’s not moving with respect to the centre of mass which defines it, which always lies on the line between the individual bodies centres of mass. The distance from the CoM of either body to the CoM of the system is proportional to the difference in their masses, and the rate of orbital motion.

“it seems very doubtful that the other 11,313 kilometres [worth of mass including the dense core] could pivot around the barycentre without significant deformation [or disintegration] of the spheroid Earth.”

The centrifugal force, throwing the dense core off to one side has a small resultant because the opposing force (maintenance of the density gradient by rotation) is relatively large.

“it is impossible to perform a control experiment [“with the Moon” and “without the Moon”] that demonstrates the barycentric Earth “wobble”.”

True, but we can measure the wobble by making parallax measurement to another body.

Cheers

Rog

No doubt there are measurements of “wobble”…
Unfortunately, nobody can isolate the causes of these “wobble”s.

• tallbloke says:

That’s how the Moon gets to go fast enough to avoid being pulled into the Earth. Being much further from the barycentre allows it to go fast in order to get all the way round in a month. The Earth doesn’t need to go fast, because it’s much heavier than the Moon. So it hugs in close to the barycenter and wobbles round it slowly to take the same time to go round as the Moon does. So the Earth doesn’t “just wobble in some way”, it rotates about the barycentre at the same number of degrees per day as the Moon does.

• malagabay says:

That’s how the Moon gets to go fast enough to avoid being pulled into the Earth.

Unless [of course] the Moon is being electro-magnetically repelled by the Earth at perigee.

Being much further from the barycentre allows it to go fast in order to get all the way round in a month.

What allows it to “go fast”… what gives the Moon its extra speed… what slows it down… and how can the Moon “get all the way round in a month” when the Moon is not actually orbiting the Earth… the Moon seems to follow some form of helical spiral dance around the Earth. Basically, the orbit path of the Moon [around the Sun] is far from explained – or understood.

The Earth doesn’t need to go fast, because it’s much heavier than the Moon.

Well I am entertained to know you have weighed the Earth and Moon.

So it hugs in close to the barycenter and wobbles round it slowly to take the same time to go round as the Moon does. So the Earth doesn’t “just wobble in some way”, it rotates about the barycentre at the same number of degrees per day as the Moon does.

So we are back to the Earth “rotates about the barycentre”… which makes the “barycentre” the pivot point for the barcentric rotation… except [of course] when the Earth and Moon don’t rotate around their “common centre of mass”… which is were you came in [if I remember rightly].

Perhaps the biggest problem with the Earth-Moon Barycentre is that it seems to be a mainstream “explanation” without any provenance or supporting observational data… it just seems to be mainstream “folklore”.

There are descriptions of very distant rotating binary star systems in the mainstream literature… but these are distant star system theories that the layman cannot observationally verify… however, the barycentric orbits within the Solar System [and especially the Earth-Moon orbital dance] can be more realistically observed and verified by the layman.

Hopefully, there will be something more substantial to discuss when someone discovers a “published paper” that actually:
1) Defines the Earth-Moon Barycentre theory.
2) Provides supporting observational data for their Earth-Moon Barycentre theory.

Exactly, the same can be said for the Sun-Earth Barycentre and the Solar System Barycentre theories.

4. tallbloke says:

“Perhaps the biggest problem with the Earth-Moon Barycentre is that it seems to be a mainstream “explanation” without any provenance or supporting observational data.”

There is extremely good supporting observational data. Based on the mainsream orbital theory, JPL calculates the positions, and correctly estimates the time at a point on Earth when Venus will start to transit the sun. They get it right to within a couple of arcseconds. It may well be that it is possible to construct an equally good alternative theory and achieve the same result, but no-one has tested one yet.

I think you are onto something with vortices though, see this:
http://tallbloke.wordpress.com/2013/02/20/a-remarkable-discovery-all-solar-system-periods-fit-the-fibonacci-series-and-the-golden-ratio/comment-page-1/#comment-44618

• malagabay says:

The JPL calculations are extremely good…
And they seem to be extremely good at predicting Venus Transits…
They just don’t seem to support barycentric orbits…
As noted by Ninderthana on your blog:

Ninderthana says: February 21, 2013 at 7:49 am

Think about it. Let’s assume that they are right and the Earth does, in fact, orbit the centre-of-mass of the Solar System (CMSS), rather than the centre of the Sun.

The location of this CMSS relative to the Sun’s centre is primarily determined by Jupiter and Saturn. When Jupiter and Saturn line up on the same side of the Sun every 19.858 years, the CMSS will be drawn out about 1.5 million km from the centre of the Sun.

Hence, there will be times when the Sun is directly between the CMSS and the Earth and so the Sun will be 1.5 million km closer than normal to the Earth, and there will be times when the CMSS will between the Sun and the Earth, so the the Sun will be 1.5 million km further away than normal.

The net effect is that Sun will move towards and away from the Earth by 1.5 million km over the cause of decades. This will change the apparent diameter of the Sun by a considerable amount.

If we compare the size of the Sun when it is closest to when it is furthest away we should see a change in apparent subtended diameter (Dtheta) of

DTheta/Theta = DR/R

Where DR = the change the distance between the Earth and the Sun (R).

DR/R is roughly 3 million km/150 million km = 0.02

Given that the Sun’s diameter is ~ 30 arc minutes this corresponds to a change in diameter of the Sun ~ 36 arc seconds!

Seriously, don’t you think that people would have measured a change in the solar diameter that is this large by now?

5. tallbloke says:

Tim, JPL’ s algorithm calculates barycentric orbits, but each planet is revolving around it’s own barycentre with the Sun, and the Sun is at the same time ‘orbiting’ or ‘wobbling’ around the barycentre of the system as a whole. It’s all very predictable, including the relativistic component, to within the limits of observation.

I’ll dig out the URL of the relevant chapter of the JPL documentation for you.

6. tallbloke says:

Here you go Tim. http://iau-comm4.jpl.nasa.gov/XSChap8.pdf
Ninderthanas comment was concerning the erroneous idea that planets orbit the solar system barycentre. They don’t. They orbit their respective Sun-planet barycentres, while the Sun threads a path between the combined gravitational forces of all the planets; i.e ‘wobbles’ around the solar system barycentre. Of course, the planets affect each other too. Jupiter and Venus cause Earth to deviate from it’s Sun-Earth barycentric orbit by around 8000km over the VEJ conjunction cycle. This is a very small percentage of the Earth’s ~300 million km diameter orbit.

• malagabay says:

So the “heavier” object “wobbles”… and the barycentre travels about the “heavier” object to reflect the orbital position[s] of the “lighter” object[s]… I’m sorry but I don’t see anything orbiting around a barycentre [pivot-point]… all I see are barycentres being continually recalculated as the objects move.

• paul says:

hi, just a note re: predictability of motion about a barycenter, be it earth moon. or earth sun, these are in fact predicted to some precision, due to their importance in high precision radial velocity measurements, and in radio studies of e.g. high speed pulsar timing. I recommend a chat with your friendly local astronomy professor with an interest in high resolution spectroscopy.
kind regards,
🙂

Comment
Delving into the realms of perception, perspective and predictability we have the mainstream promoting “predictability of motion about a barycentre”.

Unfortunately, the “barycentre” for the Earth and Moon is not a “pivot point” about which the Earth and Moon are balanced because the distance between the two objects is continually changing… the location of the “barycentre” has to be continually recalculated… in other words the mobile “barycentre” is just a mathematical artefact and not a mechanical reality.

However, once the orbital position of any two bodies becomes predictable then it is possible to predict the position of their “barycentre” via calculation.

Thereafter, mathematicians can play all sorts of semantic games with the formulae…
Like calculating the position of the orbiting objects from the “barycentre”…
But this is just a mathematical mind game… not mechanics… and my personal priority is the mechanics… not the mainstream mathematics.

7. Barycenters are best described as ‘thoughticals’…..;-)

8. thx1138 says:

With their poor understanding of gravity, I wonder how scientists and engineers get spacecraft into orbit around other planets.