Mars Magnetic Fields Problem

mars2015 · 2005-05-17 20:48:36

Yes, Karov.
I do understand the basic principle of using a vast loop of current to create a planetary magnetic field. In fact, if I remember my physics correctly, the existence of an iron core inside a planet would serve to enhance the efficiency of such a field(?).
And I do realize that, given sufficient energy, engineering prowess, and human willpower, there's no fundamental reason we cannot undertake such a task.
And, what's more, I do admire your vision when it comes to planetary-scale engineering and your obvious enthusiasm for such projects. I also look forward to the time when such amazing feats of technology will be achieved - and I admit they may be closer than I imagine. Perhaps I'm too timid. Perhaps I'm forgetting what Sir Arthur C. Clarke has taught us, that most failures of prediction stem from a failure of nerve - technology almost always advances farther and faster than most of us foresee. So you may well be right to pursue this line of reasoning so vigorously.
One or two particular thoughts I'd like to air, by the way, while I'm on the subject .. I always imagine that any loop of superconducting material around Mars' equator will need to be able to carry such an enormous density of current that it's construction will be untenable for a long time. Also, I wonder whether the localized fields generated by the massive current will have detrimental effects on the environment in the immediate vicinity of the equator.
There are questions being asked here on Earth about the potential (pun unintentional .. sorry! ) for power lines near residential communities to cause cancer - and the electric current in these cases is negligible compared to the current we'll need for our Martian project. If so, will it be necessary to fence off large swathes of equatorial real estate to establish a safety buffer zone either side of the cable? ???
Admittedly, even if such a buffer zone were necessary, we may decide that it's a fair exchange - to lose so many millions of hectares of habitable area at the equator in order to allow unfettered colonization of immense areas of radiation-shielded land to the north and south. Who knows?

Personally, my hope would be to create an atmosphere dense enough to shield the surface from harmful radiation, even in the absence of a global magnetic field. I feel that this is probably a more attainable goal in the short term. Such an atmosphere, it's been established, will last for millions of years, despite the ravages of constant 'sputtering' by the solar wind and the blasts of Coronal Mass Ejections (thank you Cindy for alerting me, and perhaps others here, to the surprising power and frequency of such events. :up: )
Just touching on a 'pet theory' dear to my heart. I still have hopes that Mars is much more volcanically alive than it's been given credit for and that it may still generate a substantial global magnetic field at intervals. This pet theory, as I've often mentioned, depends to a large extent on the as yet unconfirmed ideas of Dr. J. Marvin Herndon about natural fission reactors in planetary cores.
Earth's magnetic poles reverse every so often, with the North Pole taking up residence in Antarctica and the South Pole moving to the Arctic Ocean. Have a look at http://www.gi.alaska.edu/ScienceForum/A … .html]THIS ARTICLE, called "When The Poles Flip" by Larry Gedney. :-
More than 20 years ago, the first conclusive evidence was found on the sea floors that the earth's north and south poles have switched places repeatedly over the course of geologic time. The last reversal occurred some 710,000 years ago. For most of a million years before that, the north pole was the south pole and vice versa. Epochs of shorter duration on the order of 50,000 years can be found in the geologic record, but for the most part, each seems to last between 200,000 and 1,000,000 years.
No one knows how long it takes to make the transition. It may take a few years or it may take a few thousand (a few thousand years is about the shortest time interval that can be reliably measured from sediments and lava flows on the ocean floor). What is known from measurements of remnant magnetism in ancient pottery shards is that the earth's magnetic field has weakened by more than 50 percent in the past 4,000 years. In other words, we may be headed into another reversal.
If Mars is still geologically active, it seems reasonable to assume that its poles reverse periodically too - perhaps more sluggishly than Earth's since its smaller volume means it's probably losing energy to space faster.
It follows that it must also have intervals during which there is no global field, just as Earth does. In the case of Earth, these intervals may be years long or thousands of years long - no one knows for sure - and any such intervals on Mars may be correspondingly longer.
My view is we could conceivably have arrived at Mars, just by chance, during one of these pole reversals. We could be pleasantly surprised, in the millenia to come, to find our Martian colonies protected by a brand new natural magnetic field, without having to create it ourselves using mega-engineering.
On that 'Pollyanna-style' note of fairy tale optimism, I'll sign off. :laugh:
(Thanks for your patience. :;): )

I wonder if we could give Mars a larger Moon in proportion to Mars as Luna is to Earth and give Mars a good tug. This might reactivate the magnetosphere and also volcanism.

But where would we get this moon, and how to get it there? Ceres, maybe?? Vesta??

karov · 2005-05-20 05:56:08

Yes, I think it is in principle possible to shift the orbit of some of the Great four astreroids ( Ceres, Vesta, Palas, Hygeia) to be captured as Martian luna.

Luna is ~300 000 km off-earth and weights -- 7.35x10exp22 kg
Ceres has mass of ~10exp21, i.e. 1/73.5th of the Lunar one.

The tidal interaction between a planet and its moon is in ratio with the cube of the orbits radius. And proportional to the masses involved.

That means: Puting Ceres in about ten times closer orbit to Mars, should give comparable tidal action. At lesat sufficient to move the core slightly different than the above solids, and to reactivate strong Martian magnetism.

Ceres in ~30 000 km high orbit above Mars will be well beyond the martian Roche`s limit of about 5000 km.

A 1000 km object ( four times smaller than the Moon) in 10 times closer distance, will occupy 25 times bigger portion of the Martian skyes than Moon of earth`s ones.

karov · 2005-06-05 09:45:11

And I mentioned this but now to stress on it:

The planetary magnetism ( and geomagnetism here ) is most probably provided by the excitation of magfield by the elerctric currants flowing in the molten phases of the planetary interiors...
But to recreate this molten state is necessary really huge investment of energy, as shown in the "Antimater deposition..." scenario. Most of the energy is lost in inefficient in mag-sence just melting the interior rocks. If wedn`t need in such mega-invasive way to reactivate plate or other type of tectonics, but just to create or amplify in great degree the planetary magnetic field --

Why not just electromagnetize it?

The semi-frozen martian inner iron core is still composed of generally feromagnetic material. Puting massive coil around the planet would turn it in enormous electromagnet!!!

karov · 2005-06-05 09:51:54

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

"...The simplest type of electromagnet is a coiled piece of wire. A coil forming the shape of a straight tube (similar to a corkscrew) is called a solenoid; a solenoid bent so that the ends meet is a toroid. Much stronger magnetic fields can be produced if a "core" of paramagnetic or ferromagnetic material (commonly iron) is placed inside the coil. The field produced by the coil causes the iron to magnetize and generate a field of its own. This field can be hundreds or thousands of times stronger than that of the coil itself..."

Stormrage · 2005-06-27 16:03:53

Why don't we drill into the core and detonate nukes just like the movie The Core.

karov · 2005-06-27 23:52:42

Drilling would take much more energy that the bombs would release. The nukes are too weak for such job - you`d need TRILLIONS of them to have some noticeable effect.

Dragoneye · 2005-08-18 11:02:39

Personally i dont think its just the core thats the problem its the fact that it has 3 moons pulling on the planet screwing arround with the cores stability. thus the magnetic fields would be off....

karov · 2005-08-30 03:10:18

That`s it - difference in the move of electrically or magnetically charged pieces of matter. Plasma/M2P2 cushion is better for Mars or minor bodies.

http://www.universetoday.com/am/publish … ml?2982005

MarsDog · 2005-09-12 15:33:44

"Since there's no such thing as a free lunch, I think you'd have to pump energy into your cable to maintain the current, even if the cable is superconducting"

A superconducting loop on Mars could be used as a generator, deriving power from changes in the solar wind. If you stored some of the peak power, it could be used during lower solar wind conditions.

On Earth, the effects of solar storms occasionally knock out power transmission lines, indicating high peak power possibilities.

Controlled directionality could be attained with several coils, decelerating some of the plasma, to be captured by Mars's gravity.

An example of a generator http://www.qsl.net/ns8o/Induction_Generator.html
http://www.qsl.net/ns8o/schem.jpg

Some free power and a protective magnetic field capturing the solar wind may be possible ?

karov · 2005-09-13 09:04:46

MarsDog, I absolutely agree!
Indeed superconducting coil turns the place in electromagnet or just warpes it with electromagnet. From thee other hand - such electromagnetic coil interacting with solar wind is MHD generator i.e. mag-sail. Make it spherical with M2P2 plasma magnet means, and you have three-in-one:
- artificial magfield
- power generator
- atmosphere retainer

There is enormous freedom in the actual topological design: It may occur very usefull and efficient if the cable iss not run onto the surface, but in polar orbit , kept like sunflower by solar sails or the plasma currant of the solar wind itself in strictly perpendicular direction to the ion stream upwards from the Sun... In that cases the structure could handle indeed the excess of energy resulting from the solar flares and storms for later use during calm periods, when it is not necessary the shield to be so much stiffened...

It is like prrotection with possitive back loop. As worse is the hit, as stronger is the responce.

noosfractal · 2005-10-17 20:55:18

A new map of Mars’ magnetic field
http://www.nasa.gov/vision/universe/sol … lates.html

noosfractal · 2005-11-05 21:43:44

MarsDog, I absolutely agree!
Indeed superconducting coil turns the place in electromagnet or just warpes it with electromagnet. From thee other hand - such electromagnetic coil interacting with solar wind is MHD generator i.e. mag-sail. Make it spherical with M2P2 plasma magnet means, and you have three-in-one:
- artificial magfield
- power generator
- atmosphere retainer

karov, your post about M2P2 lead me to do some research on the topic, and ... these things are the closest thing we have to StarTrek force fields!

This 2001 paper by Winglee ...

http://www.ess.washington.edu/Space/M2P … elding.pdf

discusses using M2P2 plasma magnets up to "a few thousand kilometers" in diameter to shield interplanetary travelers from even the harshest radiation (gamma and SEP). The reference case is a 1000 km bubble generated with 100 kW and a kilogram of helium per day. The magnetic field is generated with a 200 mm (8 inch) electromagnet generating a field strength between 0.1 and 1.0 Tesla. This is doable today. The biggest difficulty is that the field has to be pulsed to avoid becoming a magsail and changing the vehicle's trajectory.

The diameter of Mars is 7800 km. If we can do a 1000 km shield by, say, 2020, there should be no reason we can't do a 20000+ km shield by 2050.

I wonder if plasma bubbles can be made into optical lenses and mirrors?

Maybe focusing the solar wind through the center of a plasma toroid could be used to heat the Martian poles.

8)
_

karov · 2005-11-06 05:48:24

Noosfractal,

Thank you for the material, it actually confirmes my insites, -- i.e. s.t. which I search for long time ago.

Yes, the 1000 km plasma magnetosphere needs , as you pointed, only 100 kW ( average car power output) and dozens of cantimeters of hardware, and about a kilo of helium per day.

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

I think a M2P2 martian >20,000 km wide plasma magnetosphere could be done even now:
- the energy of several MWatts (?) comes from the solar wind. A way to harvest it is to utiliize changes in the M2P2 "cushion" caused by the ion impacts.
- the necessary helium and/or hydrogen ( mainly! ) to replenish the system comes again from the solar wind, which doesn`t this time blows away the other atmospheric gases, but IT IS SUCKED in... The average ion speeds in the solar wind are from 200 to 800 km/s, far far exceeding the escape velocity at the eventual terraformed martian exobase of several hundreds of m/s, so indeed this artificial magnetosphere could well self-power itself.

The ways an atmosphere to escape are mainly three:
- thermal exobase escape,
- ion magnetical-pick up
- direct hydrodinamical pouring out of the gravity well

With self-powering and selfmaintaining M2P2 magnetosphere ( say installed in the normal biosphere ), even quite close to the central star and quite small world could sustain practically forever earth-equivalent atmosphere...

When I have time ( using the data and knowledge provided by you ) -- I believe I`ll be able to prove you that say - Ceres could be terraformed without solid roofing. It would have tremendously DEEP atmosphere - at least 30 times deeper than the Earth`s troposphere ( i.e. clouds forming at 240-250 km over the surface on hight where the gravity is down >2 times lower than on surface, tropopause "cold trap" on hight where the gravity is >4 times lower, strange world where scale hight is really AFFECTED by the exponential decrease of the gravitation ), really giant in radius Magnetosphere ( as big perhaps as the Earth`s one or bigger, and more intensive may be), but this AIR-world possessing so small solid state gravity anchor to keep the air and water, still stabile and habitable, AS THE SUN BURNS.

About the synthesis of magnetic and optical systems -- please google for "dusty plasma sails" ... really interesting materials. Make the dust particles smart as microbes/bacteria and you have global, PLANETARY ecosystem which activelly provides homeostasis of the INSOLATION and atmosphere retention....

Dook · 2005-11-06 06:54:05

It sounds like this M2P2 magnet is a great idea to protect a crew travelling to mars from hazardous solar radiation but how would it affect the vehicles onboard systems?

Also if it acts like a sail to change the vehicles course then simply launch at a shallower angle to mars and use the solar wind to make the necessary direction change. If your magnet fails you would have to use more fuel than intended for course corrections though.

I don't see how a large magnetic torus focussing the solar wind would create heat though. I don't believe infrared radiation is affected by the earth's magnetosphere or else we'd have a very, very, cold planet.

karov · 2005-11-06 10:36:55

I don't see how a large magnetic torus focussing the solar wind would create heat though. I don't believe infrared radiation is affected by the earth's magnetosphere or else we'd have a very, very, cold planet.

It can`t. But with plasma confined in by itself generated magnetosphere, in which plasma are suspended dusty particles with the necessary optical and EM interacting properties, than the whole cloud obtains certain EM radiation difraction/deflection properties. Thus the dusted plasma sphere could act as device concentrating or distracting light and IR from or away an object. Toriodal form, not quite good, but such artificial planetary magnetospheres, can have quite sophisticated shapes in order to fullfill better such tasks.
Remember Paul Birch, 3th type of Dyson sphere, Drexler... about the lightest possible mirrors, for use as solar sails... with dusty plasmas, orders of magnitude lighter ( lower areal density ) sails could be produced ( or rather provided ).

About the dusty plasmas:

http://www.google.com/search?hl=en&q=dusty+plasma

http://www.google.com/search?hl=en&lr=& … tnG=Search

noosfractal · 2005-11-07 02:48:29

I believe I`ll be able to prove you that say - Ceres could be terraformed without solid roofing. It would have tremendously DEEP atmosphere - at least 30 times deeper than the Earth`s troposphere ( i.e. clouds forming at 240-250 km over the surface on hight where the gravity is down >2 times lower than on surface, tropopause "cold trap" on hight where the gravity is >4 times lower, strange world where scale hight is really AFFECTED by the exponential decrease of the gravitation ), really giant in radius Magnetosphere ( as big perhaps as the Earth`s one or bigger, and more intensive may be), but this AIR-world possessing so small solid state gravity anchor to keep the air and water, still stabile and habitable, AS THE SUN BURNS.

Awesome! First we should move it to one of the Lagrange points - forget O'Neill cylinders. With such low gravity, flight will be natural. What a wonderful space port it will make.

About the synthesis of magnetic and optical systems -- please google for "dusty plasma sails" ... really interesting materials.

Wow. Dusty plasma puts everything else to shame. Everyone is talking about lightsail/magsail hybrids - and fair enough - but you can also make the insanely large mirrors and lenses required for terraforming and power beaming - including interstellar power beaming. I may actually witness the arrival of an interstellar probe at Alpha Centauri in my lifetime. 8)

Here is a Feb 2002 presentation on dusty magsails ...

http://bex.nsstc.uah.edu/RbS/HTML/STAIF02/img0.htm

A 30 km dusty magsail with a 100 kg payload is predicted to achieve a constant acceleration of 2% of g. That's 36 days to Mars.

For propulsion, you need a dusty plasma ring rather than a bubble or lens. They'll look like the rings of Saturn when operational.

Here is an April 2004 detailed NASA study on the concept ...

http://dosxx.colorado.edu/~delamere/NAS … 213143.pdf

The report says Winglee is too optimistic about the pure magsail - something happens at the 25 km mark that Winglee doesn't take into account. But it says a 1 km dusty magsail has the same performance as a 100 km pure magsail and recommends further study. No kidding!

_

noosfractal · 2005-11-07 03:14:32

It sounds like this M2P2 magnet is a great idea to protect a crew travelling to mars from hazardous solar radiation but how would it affect the vehicles onboard systems?

Apparently the induced magnetic field at the vehicle would be on the order of 1 gauss which is the same as the natural magnetic field at the Earth's surface.

Also if it acts like a sail to change the vehicles course then simply launch at a shallower angle to mars and use the solar wind to make the necessary direction change. If your magnet fails you would have to use more fuel than intended for course corrections though.

I agree - why would you say no to free delta-v?

I don't see how a large magnetic torus focussing the solar wind would create heat though.

I was thinking of the energy in the solar wind, but further examination says you're right - it is better just to form an optical lens or mirror with dusty plasma - there is a lot more energy in the electromagnetic radiation than in the solar wind particles.
_

karov · 2005-11-07 03:34:42

Yes.

About Ceres - its gravity is too low, yeah! BUt why to relly only to thee gravity to retain and envelope of close to 1 bar pressure at the surface.
With ~3 % gees on surface, the exobase hight should be about 30 000 km.

the Hill Sphere ( http://en.wikipedia.org/wiki/Hill_sphere ) of 1 Ceres has radius of
about little more than 1000 km ( only ~ 500 km over the solid surface ), hence the lower stratosphere of the terraformed Ceres will lie within the interplanetary space, and with only the hydrodynamical pouring out the atmosphere will tend to dissipate,

BUT -- what if we confine this in an plasma magnetosphere baloon with radius > 30 000 km?

An artificial M2P2 baloon CAN retain the rarefied gases on such hight where the 1 Ceres own gravity is not only insufficient, but even is overwhelmed by th solar one.

karov · 2005-11-07 03:55:19

1 Ceres receives from 7 to 10 times less light from the Sun than Earth per unit area. In principle to insolate its sun-facing side with earth level of illmuination one needs a "lense" ( say, magnifuing soleta madee of "solar sail material" ) which has about 3 times bigger radius than the mini-planet itslef or only about 3000 km diameter ( without regarding the shear thickness of the terra-modified atmosphre providing without futher greenhouse gasses addition, about 30 times more greenhouse effect per unit area. This earthly amount of > 1 kWatt / m2 might prove itself to be excessive.

The area of 1 Ceres is about 160 times smaller than earths one.

If for solar light concentration is used dusty plasma lense installed as dust particles suspension in the artificial magnetosphere of radius > 30 000 km, with optical thikness of the normal ~1% , than this provides almost exactly the optical and solar concentration abilities of 3000 km wide nearly 100% reflectability "normal" lense...

Again, the "dust particles" in the dusty plasma could indeed be "smart", tiny nano-bots doing the necessary thing activelly - to ionize gases, redirect light, etc.

noosfractal · 2005-11-07 04:38:45

If for solar light concentration is used dusty plasma lense installed as dust particles suspension in the artificial magnetosphere of radius > 30 000 km, with optical thikness of the normal ~1% , than this provides almost exactly the optical and solar concentration abilities of 3000 km wide nearly 100% reflectability "normal" lense...
Again, the "dust particles" in the dusty plasma could indeed be "smart", tiny nano-bots doing the necessary thing activelly - to ionize gases, redirect light, etc.

They could be smart - but the amazing thing is - they don't even need to be - we can do this yesterday. When are we going to launch a test generator? Maybe it is a good thing that the Russians dumped the Planetary Society's solar sail. Maybe we can convince them to build a dusty magsail
_

karov · 2005-11-09 07:27:02

"smart" for orders of magnitude bigger efficiency.

In one of the "dusty plasma" links you may find the following very usefull for complete comprehension notions:

imagine solar sail of 3D carbon fiber mesh, the C atoms spaced from eachother as far as the molecular forces allow ... then, imagine the same mesh, but the carbon "chunks" spaced further away, and the whole structure held by external to the chemical bonding electric and magnetic forces.

In solar sailing the areal density is everything, but not only there...

The space elevators, relly on extremely strong materials, i.e. materials having close to the maximal interatomic bonding...

but, bonding could be execxuted in other ways than the chemical one -- reference the kinethic structures -- lofstrom loop, space fountain, birch`s orbital rings... all they relly for stability on balance of other interactions and forces than only to interactomic electronic bonding, and balancing much bigger per mass unit forces yileds unimaginably high tension and compression strenghts...

Dusty plasma is structure again like a piece of solid state regulary matter, but the nature gives us lots more opportunities to assemble things. The structure is how thee things are connected in a whole thing.

The kinethic structures as space fountain and dusty plasma or living creature are also adaptive, they always use the energy streams that usually destroy them if passive, to activelly "stand".

Thus a dusty plasma baloon encompassing planet, moon, settlement or ship, is in far better possition in terms of lifespan and durability , than a "naked" and unwise static planetary atmosphere, cause the kinethic structure UTILIZES the solar EM and particle radiation to remain structured.

the almost hipothetical "dusty plasma" is just one possible answer of our hypothetical questions "how to...?" - make ligher solar sails, to illuminate distant places or retain atmospheres, but the important thing is that it is wrong to count in only the "natural" play of gravity and exobase temperatures in solving such "equations"...

EM is intensive and handable...

SpaceNut · 2005-12-13 08:46:09

Hundreds Of Auroras Detected On Mars

You might all be wondering what this has to do with Mars and a magnetic field. The way that these Auroras are produced is quite different from those here on earth in that they are occuring over the large areas of magnetic material.

According to the physicists, the auroras on Mars aren't due to a planet-wide magnetic field, but instead are associated with patches of strong magnetic field in the crust, primarily in the southern hemisphere.

Could one concentrate the ore into a more proper location towards the center of the planet to jump start a field?

Is there just still to litte ore that is magnetized?

SpaceNut · 2015-11-22 22:28:37

Fixed another shifting topic to find a few more gems for how to get a magentic field going by tidal forces with regards to moving the Great four astreroids ( Ceres, Vesta, Palas, Hygeia) to be captured as Martian luna not counting on Nasa.

Mars_B4_Moon · 2024-04-13 01:51:45

Study determines the original orientations of rocks drilled on Mars
https://news.mit.edu/2024/study-determi … -mars-0304
The “oriented” samples, the first of their kind from any planet, could shed light on Mars’ ancient magnetic field.

'Almost unbelievable': Rare void from the sun briefly blew up Mars' atmosphere last year, and it could happen to Earth too
https://www.livescience.com/space/mars/ … -earth-too

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) Orbiter — which has been circling the Red Planet's upper atmosphere since 2014 — witnessed Mars' magnetic shield, or magnetosphere, swell outward by "thousands of miles," researchers wrote in a statement. This enabled the wispy Martian atmosphere to temporarily expand and fill the extra space.

How to Give Mars an Atmosphere, Maybe
https://astrobiology.nasa.gov/news/how- … ere-maybe/

Void · 2024-04-13 10:56:54

The idea of a magnetic field for Mars has been an exciting one, but recent information suggests that it is not needed.

https://newmars.com/forums/viewtopic.ph … 05#p221605

If you go to minute 8.06 of this video it is suggested that the losses have not been that much: https://www.patreon.com/posts/interstel … -102029505

It is said that over 3.9 billion years they calculate that Venus would have lost .02 to .6 meters of water to the solar wind. And they think that Mars is somewhat the same.

I am willing to say that it is not certain how much good a magnetic field might do.

This will be interesting for Red Dwarf worlds as well. They may have greater power to hold an atmosphere than has been thought.

Done

Last edited by Void (2024-04-13 11:05:28)

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