Posted on 06/16/2009 9:29:47 AM PDT by BGHater
A radical new idea may revolutionise our understanding of one of the most vital forces on Earth
Earth's magnetic field, long thought to be generated by molten metals swirling around its core, may instead be produced by ocean currents, according to controversial new research published this week.
It suggests that the movements of such volumes of salt water around the world have been seriously underestimated by scientists as a source of magnetism.
If proven, the research would revolutionise geophysics, the study of the Earth’s physical properties and behaviour, in which the idea that magnetism originates in a molten core is a central tenet.
Earth’s magnetic field is vital for life, extending tens of thousands of miles into space and protecting the planet against radiation that would otherwise burn away the atmosphere and oceans.
However, its origin was a mystery until early last century when Albert Einstein said understanding the phenomenon was one of science’s most important tasks. This provoked a debate which concluded with scientists agreeing that magnetism must originate in the Earth’s core.
“Everyone accepted this, but in reality there has never been any proof,” said Gregory Ryskin, associate professor of chemical and biological engineering at Northwestern University in Illinois. “It is just an idea we have accepted for a long time without questioning it enough.”
His research suggests that Earth’s magnetism is actually linked to ocean movements. The salt in seawater allows it to conduct electricity, meaning it generates electrical and magnetic fields as it moves.
The findings, published by Britain’s Institute of Physics’s New Journal of Physics, will cause a fierce scientific debate.
(Excerpt) Read more at timesonline.co.uk ...
| Planet | g | vesc | distance | albedo | temperature | atm. press. | atm. comp. | rotation | mag. field |
|---|---|---|---|---|---|---|---|---|---|
|
|
(* gE) | (km/s) | (A.U.) | (%) | (K) | (* Earth's) |
|
|
(* Earth's) |
| Mercury | 0.378 | 4.3 | 0.387 | 5.6 | 100 night, 590--725 day |
10-15 | 98% He, 2% H2 | 58.81 d | 0.006 |
| Venus | 0.907 | 10.36 | 0.723 | 72 | 737 | 92 | 96.5% CO2, 3.5% N2, 0.015% SO2 |
243.69 d | 0.00 |
| Earth | 1.000 | 11.186 | 1.000 | 38.5 | 283--293 day | 1.000 | 78.084% N2, 20.946% O2, 0.934% Ar, 0.035% CO2, H2O highly variable (< 1%) |
23.9345 h | 1.000 |
| Mars | 0.377 | 5.03 | 1.524 | 16 | 184--242 day | 0.007--0.009 | 95.32% CO2, 2.7% N2 1.6% Ar, 0.13% O2, 0.08% CO, 0.021% H2O, 0.01% NO |
24.623 h | 0.00 |
| Jupiter | 2.364 | 59.5 | 5.203 | 70 | 165 | > > 100 | 89% H2, 11% He, 0.2% CH4, 0.02% NH3 |
9.925 h | 19,519 |
| Saturn | 0.916 | 35.5 | 9.539 | 75 | 134 | > > 100 | 89% H2, 11% He, 0.3% CH4, 0.02% NH3 |
10.50 h | 578 |
| Uranus | 0.889 | 21.3 | 19.182 | 90 | 76 | > > 100 | 89% H2, 11% He | 17.24 h | 47.9 |
| Neptune | 1.125 | 23.5 | 30.06 | 82 | 72 | > > 100 | 89% H2, 11% He | 16.11 h | 27.0 |
| Pluto | 0.0675 | 1.1 | 39.53 | 14.5 | 50 | 0.003 | CH4, N2 | 6.405 d | 0.00 |
last updated: 21 May 2001
Does it have to be either/or, or can it be “YES!” to both?
Wouldn’t be that surprised to see the ocean scenario as a contributing player.
Should have seen the “erosion” readings I got from a slurry sample decades ago.
I used a probe in a water/ore-particle slurry that was connected such that the hesitance of the probe was monitored, with the resistance change as the probe wore away being used to calculate the projected erosion of pipeline to carry the slurry from an iron mine to the mill. Problem was, the slurry was rotated past the probe in the vessel, and it contained magnetite.
Rotating magnetic particles and a steel probe = generator! The engineers I was working for had to design a new test method.
This could be a somewhat analogous macro-situation.
The magnetic field of Jupiter is largely due to a core of metallic hydrogen, which exists due to the high core pressures at Jupiter’s center. Same would apply for any other gas giant of similar structure. Might also apply for brown dwarves, however there are higher core temperatures due to gravitational contraction (plus any short lived fusion reaction, either involving deuterium and/or lithium). So that further reinforces the molten core of terrestrial planets (Mars may have lost its field due to the core cooling to the point of no longer being liquid).
The ocean theory could explain why Venus has no magnetic field, despite being almost the same size and composition as Earth.
Thanks ApplegateRanch.
Speaking of sediment, I wonder if I posted that other article on here...
What did they do for the new test method?
Cheers!
At this point, I really don’t remember what they came up with. I was “Johnson’s War on Poverty Diversitied-out” soon after, and ended up in a new area, doing totally different work...until I got “Cartered”, and zigged again.
The rotation period of Venus is however about the same as its orbital period, inferring a tidal lock with the sun. Such a tidal lock may have likely inhibited core rotation as well. Then again Mercury has a weak field, and is in a similar tidal lock situation.
Let me check some info on the Jovian moons, as in small bodies in close proximity with the central object of the system.
Jovian moons:
As an example, Ganymede and Callisto, two of the large (Galilean) moons. Ganymede and Callisto are both in tidal lock with Jupiter, so their rotational periods are in sync with their orbital periods. Ganymede has an iron core and a probable subsurface ocean, and also has its own independent magnetic field. Ganymede is close enough for Jupiter to exert some tidal heating - keeping the core liquid?
Callisto, while in tidal lock, not so much to cause tidal heating. However Callisto is theorized to have a silicate core. Callisto may also have a subsuface ocean, enough so that it locally influences the magnetic lines of force from Jupiter’s field, since the water - with dissolved salts - being an excellent electrical conductor. But it does not have its own independent field - as found by various probe missions.
Europa is anothe moon that is also in tidal lock, has a subsurface ocean, and an iron core, likely solid. No independent magnetic field, just an induced field due to Jupiter’s field for the same reason as Callisto. Europa is the smallest of the Galilean moons, so perhaps its mass is not enough for tidal heating to keep the iron core in a liquid state.
Io is the closest of the Galilean moons, and is subject ot a lot of tidal heating - thus its volcanic activity and sulfur plums. Iron core, but no independent field (however the flux from Jupiter may be overwhelming any measurement of a field from Io, but for now the core of Io is suspected of being non-convecting, therefore solid (? )). Io is a strange beastie though.
Tectonic action would create enormous pressures on crystalline rock, generating electrical forces such as those seen in geologically active earthquake zones, and volcanic zones.
Depending on the makeup of the local crust, conductivity and possibly even "semiconductivity" ( silicon diodes ) could be possible. ( Semiconductivity would be akin to conduction of electricity in one direction, but high resistance in the other, resulting in a sort of directional current flow. )
If electromagnetic forces were being created from the frictional and pressure forces of tectonic subduction at the threshold of mantle and crust, it's possible the two dissimilar layers transfer that electrical force into the mantle much like a transformer uses a solid metal core.
The result is the core producing an amplified electrical field on a planetary scale.
Earth’s magnetic field is not produced by an internal dynamo within the planet
Dennis Brooks | 2009 | Dennis Brooks
Posted on 10/27/2009 11:12:33 AM by mudblood
http://www.freerepublic.com/focus/news/2371982/posts
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