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#126 2021-08-05 13:31:49

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,616

Re: Artificial Magnetosphere - Electromagnetic Induction

For Void re Post #125

The idea of lifting mass to orbit using magnetic force is new to me, but it is certainly not at all surprising coming from you!

Best wishes for success with the idea ... while the idea itself may need some time to bear fruit, the ** related ** ideas it generates in the minds of your readers may well be the produce we humans will harvest.

I find myself wondering (as just one example) if a magnetic force could be great enough to equal or exceed the pull of Earth's gravity at a distance of 100 miles/ 162 km.  Certainly inside a star such forces must be routine.

As you know, both gravity and magnetic force fall off at comparable rates with distance ...

I asked Google for help, and it came up with this for gravity:

Image result for distance of gravity force squared
Since gravitational force is inversely proportional to the square of the separation distance between the two interacting objects, more separation distance will result in weaker gravitational forces. So as two objects are separated from each other, the force of gravitational attraction between them also decreases.

Newton's Law of Universal Gravitation - The Physics Classroom
https://www.physicsclassroom.com › circles › Lesson-3
About featured snippets

I'm fairly confident that relationship holds for magnetic force as well.

However, magnetic force has the distinct advantage that (unlike gravity) it can be pointed.

Accordingly, a clever person (we have some already in the forum) might be able to show that a bar magnet in orbit around the Earth might be able to pluck an object from the surface of the Earth.  Wouldn't ** that ** be a neat trick!

Well, it is all in a day's work for the member we have come to know as Void!

(th)

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#127 2021-08-05 13:45:44

Void
Member
Registered: 2011-12-29
Posts: 3,923

Re: Artificial Magnetosphere - Electromagnetic Induction

(th),

Thanks for your interest.  You may see better what I have in mind in the "World Rings" topic.

If we had an inertia bank account, then Phobos would have a large one.  For the Moon we would need to build one.

I do not intend to suck things to orbit by magnetism, rather to put money in the account with magnetism, and perhaps photons and other tricks.

Robotic Arm Tethers would grab stuff off the ground and so reduce the inertia of Phobos.  If you look at that other topic you will see that I have made a suggestion of sub-Magnetic Stations, so that the robotic arms can be shorter.

I am quite aware of the distance limits of magnetism per picking up objects.  But in orbit, while no one may hear you scream, gentle pushes as pulls from various orbital and surface magnetic objects may be of use for lifting mass, and as a byproduct, we might hope, protecting atmospsheres.


Done.


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#128 2021-08-05 17:19:56

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,616

Re: Artificial Magnetosphere - Electromagnetic Induction

For Void re #127

It is possible you would prefer not to consider the extension of your suggestion?

It is certainly possible I read more into your words than you intended?

However, the damage appears to be done, because this topic is about both Artificial Magnetosphere (which I support) ** and ** Electromagnetic Induction.

I'm going back to the top to see who created this topic and what was intended....

OK ... the creator and manager of this topic is: (drum roll)...RobertDyck

For RobertDyck ....

It appears that Void has (perhaps inadvertently or unintentionally) introduced a concept into your topic that I find surprising and possibly worth pursuing ...

The question that I ** thought ** Void was asking is: Is it possible to create a magnetic field of sufficient strength to pick up an object from the surface of a planet using magnetic force?

The idea would appear preposterous on it's face, so if it is examined I would expect the results to be ridiculous.

However, we are in the company of Void, who can toss off new and remarkable ideas with ease.

A magnetic field of sufficient strength to pick up an object from the surface of the Earth would most certainly disturb the magnetic field of Earth.  But Mars ** has ** no magnetic field to disturb.

Neither does the Moon, for that matter.

Update at 19:47 local time ...

For Void ... is there such a thing as a telescoping solenoid?

I have never heard of one.

But I am seeing (in my mind's eye) a telescoping solenoid that extends from a location in orbit around a body until it's tip touches the surface, at which point magnetic force pulls the solenoid back to space.

A space tether is limited by the strength of electrostatic force.  Specifically, the force that holds two atoms in close association is the sharing of electron shells.  But magnetic force is (potentially) far stronger than electrostatic force can ever be.

Accordingly, it seems possible (in my ignorance to be corrected shortly) that a telescoping solenoid could be stronger than a rope made of material held together by electrostatic forces.

Thus, a "spring" of magnetic force could (presumably) lift a mass against the pull of gravity.

We could begin an analysis of the question by testing to see whether a magnetic field can lift a mass against the pull of gravity.

(th)

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#129 2021-08-05 18:54:58

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,345

Re: Artificial Magnetosphere - Electromagnetic Induction

Magnetic field intensity drops off quite quickly with distance from its source so a ring will not attract much from a surface that is below it since we would need to have a huge attracting field.

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#130 2021-08-05 19:04:25

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,616

Re: Artificial Magnetosphere - Electromagnetic Induction

For SpaceNut re #129

Thanks for the reminder of the inverse square law as it applies to magnetic fields!

It is important to keep that "feature" of nature in mind as we proceed!

Update at 22:23 local time ...

The arrangement I attempted to describe in an earlier post is called "nested" solenoids ...

Google found these citations when I inquired:

Two nested solenoids and their magnetic fields | Physics ...
https://www.physicsforums.com/threads/two-nested...
Feb 03, 2021 · Homework Statement: We have 2 solenoids. The smaller (2) is inside the large one (1) with the axes aligned. Length1 is 0.63, radius1 0.051 m and N1 670 turns. The smaller length2 0.23 m, radius2 0.031 m and N2 260 turns. The larger solenoid …

Two solenoids are nested coaxially such that their | Chegg.com
https://www.chegg.com/homework-help/questions-and...
Two solenoids are nested coaxially such that their magnetic fields point in opposite directions. Treat the solenoids as ideal. The outer one has a radius of 20 mm, and the radius of the inner solenoid is 10 mm. The length, number of turns, and current of the outer solenoid are, respectively, 20.5 cm, 541 turns, and 5.11 A. For the inner solenoid …

Solved: Two Solenoids Are Nested Coaxially Such That Their ...
Question 4 of 19 > Two solenoids are nested coaxially ...
Solved: Two Ideal Solenoids Are "nested" (aligned Concentr ...
See more results
Nested Consider two nested solenoids centered on the x ...
https://www.coursehero.com/file/p75nq03/Nested...
Nested Consider two nested solenoids centered on the x axis The larger solenoid from PHYS 2213 at Cornell University

It should be possible to build a working model of a telescoping set of solenoids able to lift an object against a gravitational field.

A single solenoid can lift an object against a gravitational field.

(th)

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#131 2021-08-05 20:56:44

Void
Member
Registered: 2011-12-29
Posts: 3,923

Re: Artificial Magnetosphere - Electromagnetic Induction

I would like to ask forgivness in advance from Robert, if I have deviated from the
core topic too far.  I would be willing to self modify what I have presented per
any reasonable request by him.

(th),  If you look at the videos in the topic "World Rings", there are teachings
about space thethers.  It is felt by some that for Mars it would not be that hard
to use tethers to assist the trasfer of mass from Martian surface to orbits.  These
, it is hoped, would give a more sudden exchange of position and speed to an object
to manipulate.  They could be attached directly to Phobos and use it's stored orbital
energy to lift objects, if not directly from the Martian surface at least from a
smaller version of Starship, that would only project itself to sub-orbit.

Where my logic about magnetism comes in is that some peopole have suggested blocking
diverting the solar wind to protect Mars.  I believe that the ideas I have seen
have a magnet in the L1 location.  That is quite an amount of force.  If you had
a magnetic solar sail the size of Mars and then some, it would really be able to move
some mass.  But what I am after is to have many magnetic fields, throttled as needed,
and working together, to both transfer solar wind momentum into Phobos, and to protect
the Martian atmosphere.  If this could be done, then the lifting of mass from the
Martian surface would be better facilitated.  And this suits me fine, as I believe
that we not only want to inhabit the surfaces of worlds, but the orbits around them.
The orbits around Mars would provide abundant energy with which to warm Mars to a
degree.

I have similar thinking for the Moon.

Done.


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#132 2021-08-06 03:19:47

knightdepaix
Member
Registered: 2014-07-07
Posts: 239

Re: Artificial Magnetosphere - Electromagnetic Induction

To tahanson43206 #124

It seems my post #120 help bring more attention to celestial body's atmosphere than magnetosphere. Could nuclear waste from the Earth be dumped onto the Martian core to generate heat and help remelt the core? The Martian gains a giant income source as the dumping site of radioactive waste.

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#133 2021-08-06 05:39:17

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,616

Re: Artificial Magnetosphere - Electromagnetic Induction

For knightdepaix re #132

It is good to see your ideas picked up and developed.

Can your suggestion for disposal of radioactive waste work equally well if the Sun is the destination? 

I don't know the answer, but perhaps it is readily available ... Is the energy cost of deceleration to drop a load into the Sun greater or less than the energy cost of acceleration to Mars?

One thing seems certain. The energy cost of lifting a load of radioactive waste to orbit will be in competition with other payloads that might have more immediate value.

Can you justify lifting radioactive waste from Earth instead of people or supplies for their activities?

That would be a good exercise of weighing relative values, in any case.

(th)

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#134 2021-08-06 07:57:29

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 1,197

Re: Artificial Magnetosphere - Electromagnetic Induction

The amount of heat needed to raise the temperature of 1billion cubic miles of molten rock and iron by anything you could even measure, would be far beyond realistic human capabilities.  And there is no way of drilling through 3000km of Martian mantle to even reach the core.

One long term option though: if we terraform Mars and raise its surface temperature, geothermal heat flux will decline due to diminished temperature difference.  That is basic Fourier's law.  Radioactive decay in the core and mantle would gradually raise its temperature until heat flux is restored, at a slightly higher core temperature.  But we are talking small increases in temperature, over a time frame of millions of years.  I cannot see any realistic way of directly heating the core.


Interested in space science, engineering and technology.

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#135 2021-08-06 13:42:39

Void
Member
Registered: 2011-12-29
Posts: 3,923

Re: Artificial Magnetosphere - Electromagnetic Induction

I think this is on topic, but perhaps it has been posted already elsewhere.
https://www.nationalgeographic.com/scie … ars-center
Quote:

Core of Mars is shockingly big, NASA’s InSight mission reveals

https://sputniknews.com/us/202107231083 … lten-core/

https://www.reddit.com/user/inficoreal/ … s_insight/

https://hypebeast.com/2021/7/nasa-insig … s-revealed

Perhaps the core does not have convection in the way Earth does.

You can look at two types of lakes.

A fresh water lake will turn over in spring and fall as the top water may become heavier than the bottom water.

However a brine lake such as in Antarctica, may not turn over due to salt layers stratifications.

I have wondered if the same stratification could have occurred for the Martian core.
If that were true, then it is possible that Mars has retained more heat than expected.  However it might just be that the liquid of the core of Mars is of a nature
that it can be liquid at cooler temperatures than that of Earth.  So, of course I don't know if it is stratification or a cooler liquid.

But no magnetic field I guess.

Done.

Last edited by Void (2021-08-06 13:56:09)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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