Can a magnetic field of an object be stronger than its gravity?Why Did Mars lose its Magnetic Field?Were effects of a planetary magnetic field reversal observed on other planets than Earth?Does the Moon's magnetic field affect Earth's magnetic field?If the moon still had a magnetic field how long would have been possible to keep an atmosphere?Are a black hole's jets caused by the black hole's magnetic field?Why did Venus not lose its atmosphere without magnetic field?How does the Sun generate its periodically reversing large-scale magnetic field?Is it possible to tell if a certain extrasolar planet produces its own magnetic field?Are all gas planets guaranteed to produce their own magnetic field?What could possibly save an atmosphere other than a magnetic field? Why can't a magnetic field save the atmosphere in certain cases?

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Can a magnetic field of an object be stronger than its gravity?


Why Did Mars lose its Magnetic Field?Were effects of a planetary magnetic field reversal observed on other planets than Earth?Does the Moon's magnetic field affect Earth's magnetic field?If the moon still had a magnetic field how long would have been possible to keep an atmosphere?Are a black hole's jets caused by the black hole's magnetic field?Why did Venus not lose its atmosphere without magnetic field?How does the Sun generate its periodically reversing large-scale magnetic field?Is it possible to tell if a certain extrasolar planet produces its own magnetic field?Are all gas planets guaranteed to produce their own magnetic field?What could possibly save an atmosphere other than a magnetic field? Why can't a magnetic field save the atmosphere in certain cases?













19












$begingroup$


Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?










share|improve this question











$endgroup$







  • 3




    $begingroup$
    interesting question!
    $endgroup$
    – uhoh
    May 30 at 4:40






  • 23




    $begingroup$
    Gravity and electromagnetism both have infinite range.
    $endgroup$
    – user76284
    May 30 at 8:40






  • 2




    $begingroup$
    Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
    $endgroup$
    – jamesqf
    May 30 at 16:44






  • 2




    $begingroup$
    Magnetic field and force have different units/dimensions and cannot be compared directly.
    $endgroup$
    – Rob Jeffries
    May 31 at 7:37






  • 1




    $begingroup$
    @Jamesqf Proton precession ...?
    $endgroup$
    – Russell McMahon
    May 31 at 11:37















19












$begingroup$


Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?










share|improve this question











$endgroup$







  • 3




    $begingroup$
    interesting question!
    $endgroup$
    – uhoh
    May 30 at 4:40






  • 23




    $begingroup$
    Gravity and electromagnetism both have infinite range.
    $endgroup$
    – user76284
    May 30 at 8:40






  • 2




    $begingroup$
    Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
    $endgroup$
    – jamesqf
    May 30 at 16:44






  • 2




    $begingroup$
    Magnetic field and force have different units/dimensions and cannot be compared directly.
    $endgroup$
    – Rob Jeffries
    May 31 at 7:37






  • 1




    $begingroup$
    @Jamesqf Proton precession ...?
    $endgroup$
    – Russell McMahon
    May 31 at 11:37













19












19








19


7



$begingroup$


Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?










share|improve this question











$endgroup$




Can a planet, star or otherwise have a magnetic field that is stronger or have more range than its gravity?







gravity fundamental-astronomy magnetic-field stellar-astrophysics stellar-dynamics






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited May 31 at 18:54







Muze

















asked May 30 at 0:11









MuzeMuze

856425




856425







  • 3




    $begingroup$
    interesting question!
    $endgroup$
    – uhoh
    May 30 at 4:40






  • 23




    $begingroup$
    Gravity and electromagnetism both have infinite range.
    $endgroup$
    – user76284
    May 30 at 8:40






  • 2




    $begingroup$
    Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
    $endgroup$
    – jamesqf
    May 30 at 16:44






  • 2




    $begingroup$
    Magnetic field and force have different units/dimensions and cannot be compared directly.
    $endgroup$
    – Rob Jeffries
    May 31 at 7:37






  • 1




    $begingroup$
    @Jamesqf Proton precession ...?
    $endgroup$
    – Russell McMahon
    May 31 at 11:37












  • 3




    $begingroup$
    interesting question!
    $endgroup$
    – uhoh
    May 30 at 4:40






  • 23




    $begingroup$
    Gravity and electromagnetism both have infinite range.
    $endgroup$
    – user76284
    May 30 at 8:40






  • 2




    $begingroup$
    Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
    $endgroup$
    – jamesqf
    May 30 at 16:44






  • 2




    $begingroup$
    Magnetic field and force have different units/dimensions and cannot be compared directly.
    $endgroup$
    – Rob Jeffries
    May 31 at 7:37






  • 1




    $begingroup$
    @Jamesqf Proton precession ...?
    $endgroup$
    – Russell McMahon
    May 31 at 11:37







3




3




$begingroup$
interesting question!
$endgroup$
– uhoh
May 30 at 4:40




$begingroup$
interesting question!
$endgroup$
– uhoh
May 30 at 4:40




23




23




$begingroup$
Gravity and electromagnetism both have infinite range.
$endgroup$
– user76284
May 30 at 8:40




$begingroup$
Gravity and electromagnetism both have infinite range.
$endgroup$
– user76284
May 30 at 8:40




2




2




$begingroup$
Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
$endgroup$
– jamesqf
May 30 at 16:44




$begingroup$
Magnetar? "The magnetic field of a magnetar would be lethal even at a distance of 1000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of life impossible": en.wikipedia.org/wiki/Magnetar
$endgroup$
– jamesqf
May 30 at 16:44




2




2




$begingroup$
Magnetic field and force have different units/dimensions and cannot be compared directly.
$endgroup$
– Rob Jeffries
May 31 at 7:37




$begingroup$
Magnetic field and force have different units/dimensions and cannot be compared directly.
$endgroup$
– Rob Jeffries
May 31 at 7:37




1




1




$begingroup$
@Jamesqf Proton precession ...?
$endgroup$
– Russell McMahon
May 31 at 11:37




$begingroup$
@Jamesqf Proton precession ...?
$endgroup$
– Russell McMahon
May 31 at 11:37










3 Answers
3






active

oldest

votes


















17












$begingroup$

Let's look at the proper magnetic force (as opposed to the Lorentz force on a moving, charged object described in @KenG's answer) on a specimen $S$ of magnetized material with mass $M_S$ as a way to try to compare. Let's arbitrarily assume it has a fixed, permanent magnetic moment $m_S$. We can't use iron because it will saturate too easily.



Then let's look at how the forces scale differently with distance



$$mathbfF_G = -fracG M_S Mr^2mathbfhatr tag1$$



$$mathbfF_B =nabla (mathbfm_S cdot mathbfB(mathbfr)) tag2$$



If we reduce these to scalar equations at a radius $R$ (assume $mathbfm_S$ and $mathbfB$ are parallel) assume all forces are attractive, and evaluate the potentials and their gradients on the equator of the body at it's physical radius $R$. Since the magnetic force on our dipole specimen drops off faster than the gravitational force, we have to evaluate the two at the closest physically possible distance:



$$F_G = fracG M_S MR^2 tag3$$



$$F_B = frac3 m_S B_r=RR tag4$$



where our specimen is a distance $R$ from our field source, and it's moment $m_S$ is a magnetization of 1 Tesla times the volume of a 1 kg rare earth magnet, about 0.000125 cubic meters.



All MKS units, all rough, ballpark numbers with emphasis on strongest magnetic fields



Body R (m) M (kg) B(r=R) (T) F_G (N) F_B (N) F_B/F_G
Earth 6.4E+06 6.0E+24 5.0E-05 9.8E+00 2.9E-15 3.0E-16
Jupiter 7.1E+07 1.9E+27 4.2E-04 2.5E+01 2.2E-15 8.8E-17
Neutron Star 1.0E+04 4.0E+30 5.0E+10 2.7E+12 1.9E+03 7.0E-10
Magnetar 1.0E+04 4.0E+30 2.0E+11 2.7E+12 7.6E+03 2.8E-09


So even for a Magnetar (see also 1, 2) a kind of neutron star with a very strong magnetic field), the magnetic force on our 1kg specimen of permanent magnet is only 3 parts per billion as strong as the gravitational force.



You might see a much more favorable ratio if you compared two subatomic particles at short ranges (e.g. 1E-15 meters) but for astronomical objects, gravity seems to win smartly.






share|improve this answer











$endgroup$












  • $begingroup$
    I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
    $endgroup$
    – Rob Jeffries
    May 31 at 7:45










  • $begingroup$
    @RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
    $endgroup$
    – uhoh
    May 31 at 7:48











  • $begingroup$
    Comments are not for extended discussion; this conversation has been moved to chat.
    $endgroup$
    – called2voyage
    Jun 1 at 22:52


















36





+50







$begingroup$

It depends on what object it's acting on. There are many objects, including stars, that have magnetic fields where Lorentz forces on charged particles like electrons and protons are stronger than the gravitational force on them.



Also remember that the strength of the Lorentz force depends on the speed of the particle moving through it, so a fast enough moving electron even here on Earth will receive a larger magnetic force than a force of gravity. This is how the Earth's magnetic field is able to contain charged particles in the Van Allen belts that its gravity could not contain.






share|improve this answer











$endgroup$








  • 1




    $begingroup$
    Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
    $endgroup$
    – uhoh
    May 30 at 4:55







  • 1




    $begingroup$
    Nice answer to a somehow ill posed question
    $endgroup$
    – Alchimista
    May 30 at 9:35






  • 1




    $begingroup$
    +1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
    $endgroup$
    – Mindwin
    May 30 at 12:38






  • 1




    $begingroup$
    @Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
    $endgroup$
    – Mindwin
    May 30 at 12:40






  • 1




    $begingroup$
    @Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
    $endgroup$
    – Muze
    May 30 at 23:08


















9












$begingroup$

It isn't impossible, but the short answer is "no".



A gravitational field will accelerate all matter and energy equally while a magnetic field will only accelerate moving electric charges (other magnets).



The force due to gravity is proportional to the inverse square of the distance, and the force due to magnetism asymptotically approaches the inverse cube of the distance. At some critical distance the gravitational force will become stronger than the magnetic force.



Unless most of the large body was magnetic, even over the magnetic poles the magnetic field would probably be too low to levitate a typical magnet in the large body's gravitational field.






share|improve this answer









$endgroup$








  • 1




    $begingroup$
    Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
    $endgroup$
    – uhoh
    May 30 at 22:49











  • $begingroup$
    Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
    $endgroup$
    – PERFESSER CREEK-WATER
    Jun 4 at 19:11










  • $begingroup$
    Still here? just wandering?
    $endgroup$
    – Muze
    Jun 5 at 1:04











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3 Answers
3






active

oldest

votes








3 Answers
3






active

oldest

votes









active

oldest

votes






active

oldest

votes









17












$begingroup$

Let's look at the proper magnetic force (as opposed to the Lorentz force on a moving, charged object described in @KenG's answer) on a specimen $S$ of magnetized material with mass $M_S$ as a way to try to compare. Let's arbitrarily assume it has a fixed, permanent magnetic moment $m_S$. We can't use iron because it will saturate too easily.



Then let's look at how the forces scale differently with distance



$$mathbfF_G = -fracG M_S Mr^2mathbfhatr tag1$$



$$mathbfF_B =nabla (mathbfm_S cdot mathbfB(mathbfr)) tag2$$



If we reduce these to scalar equations at a radius $R$ (assume $mathbfm_S$ and $mathbfB$ are parallel) assume all forces are attractive, and evaluate the potentials and their gradients on the equator of the body at it's physical radius $R$. Since the magnetic force on our dipole specimen drops off faster than the gravitational force, we have to evaluate the two at the closest physically possible distance:



$$F_G = fracG M_S MR^2 tag3$$



$$F_B = frac3 m_S B_r=RR tag4$$



where our specimen is a distance $R$ from our field source, and it's moment $m_S$ is a magnetization of 1 Tesla times the volume of a 1 kg rare earth magnet, about 0.000125 cubic meters.



All MKS units, all rough, ballpark numbers with emphasis on strongest magnetic fields



Body R (m) M (kg) B(r=R) (T) F_G (N) F_B (N) F_B/F_G
Earth 6.4E+06 6.0E+24 5.0E-05 9.8E+00 2.9E-15 3.0E-16
Jupiter 7.1E+07 1.9E+27 4.2E-04 2.5E+01 2.2E-15 8.8E-17
Neutron Star 1.0E+04 4.0E+30 5.0E+10 2.7E+12 1.9E+03 7.0E-10
Magnetar 1.0E+04 4.0E+30 2.0E+11 2.7E+12 7.6E+03 2.8E-09


So even for a Magnetar (see also 1, 2) a kind of neutron star with a very strong magnetic field), the magnetic force on our 1kg specimen of permanent magnet is only 3 parts per billion as strong as the gravitational force.



You might see a much more favorable ratio if you compared two subatomic particles at short ranges (e.g. 1E-15 meters) but for astronomical objects, gravity seems to win smartly.






share|improve this answer











$endgroup$












  • $begingroup$
    I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
    $endgroup$
    – Rob Jeffries
    May 31 at 7:45










  • $begingroup$
    @RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
    $endgroup$
    – uhoh
    May 31 at 7:48











  • $begingroup$
    Comments are not for extended discussion; this conversation has been moved to chat.
    $endgroup$
    – called2voyage
    Jun 1 at 22:52















17












$begingroup$

Let's look at the proper magnetic force (as opposed to the Lorentz force on a moving, charged object described in @KenG's answer) on a specimen $S$ of magnetized material with mass $M_S$ as a way to try to compare. Let's arbitrarily assume it has a fixed, permanent magnetic moment $m_S$. We can't use iron because it will saturate too easily.



Then let's look at how the forces scale differently with distance



$$mathbfF_G = -fracG M_S Mr^2mathbfhatr tag1$$



$$mathbfF_B =nabla (mathbfm_S cdot mathbfB(mathbfr)) tag2$$



If we reduce these to scalar equations at a radius $R$ (assume $mathbfm_S$ and $mathbfB$ are parallel) assume all forces are attractive, and evaluate the potentials and their gradients on the equator of the body at it's physical radius $R$. Since the magnetic force on our dipole specimen drops off faster than the gravitational force, we have to evaluate the two at the closest physically possible distance:



$$F_G = fracG M_S MR^2 tag3$$



$$F_B = frac3 m_S B_r=RR tag4$$



where our specimen is a distance $R$ from our field source, and it's moment $m_S$ is a magnetization of 1 Tesla times the volume of a 1 kg rare earth magnet, about 0.000125 cubic meters.



All MKS units, all rough, ballpark numbers with emphasis on strongest magnetic fields



Body R (m) M (kg) B(r=R) (T) F_G (N) F_B (N) F_B/F_G
Earth 6.4E+06 6.0E+24 5.0E-05 9.8E+00 2.9E-15 3.0E-16
Jupiter 7.1E+07 1.9E+27 4.2E-04 2.5E+01 2.2E-15 8.8E-17
Neutron Star 1.0E+04 4.0E+30 5.0E+10 2.7E+12 1.9E+03 7.0E-10
Magnetar 1.0E+04 4.0E+30 2.0E+11 2.7E+12 7.6E+03 2.8E-09


So even for a Magnetar (see also 1, 2) a kind of neutron star with a very strong magnetic field), the magnetic force on our 1kg specimen of permanent magnet is only 3 parts per billion as strong as the gravitational force.



You might see a much more favorable ratio if you compared two subatomic particles at short ranges (e.g. 1E-15 meters) but for astronomical objects, gravity seems to win smartly.






share|improve this answer











$endgroup$












  • $begingroup$
    I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
    $endgroup$
    – Rob Jeffries
    May 31 at 7:45










  • $begingroup$
    @RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
    $endgroup$
    – uhoh
    May 31 at 7:48











  • $begingroup$
    Comments are not for extended discussion; this conversation has been moved to chat.
    $endgroup$
    – called2voyage
    Jun 1 at 22:52













17












17








17





$begingroup$

Let's look at the proper magnetic force (as opposed to the Lorentz force on a moving, charged object described in @KenG's answer) on a specimen $S$ of magnetized material with mass $M_S$ as a way to try to compare. Let's arbitrarily assume it has a fixed, permanent magnetic moment $m_S$. We can't use iron because it will saturate too easily.



Then let's look at how the forces scale differently with distance



$$mathbfF_G = -fracG M_S Mr^2mathbfhatr tag1$$



$$mathbfF_B =nabla (mathbfm_S cdot mathbfB(mathbfr)) tag2$$



If we reduce these to scalar equations at a radius $R$ (assume $mathbfm_S$ and $mathbfB$ are parallel) assume all forces are attractive, and evaluate the potentials and their gradients on the equator of the body at it's physical radius $R$. Since the magnetic force on our dipole specimen drops off faster than the gravitational force, we have to evaluate the two at the closest physically possible distance:



$$F_G = fracG M_S MR^2 tag3$$



$$F_B = frac3 m_S B_r=RR tag4$$



where our specimen is a distance $R$ from our field source, and it's moment $m_S$ is a magnetization of 1 Tesla times the volume of a 1 kg rare earth magnet, about 0.000125 cubic meters.



All MKS units, all rough, ballpark numbers with emphasis on strongest magnetic fields



Body R (m) M (kg) B(r=R) (T) F_G (N) F_B (N) F_B/F_G
Earth 6.4E+06 6.0E+24 5.0E-05 9.8E+00 2.9E-15 3.0E-16
Jupiter 7.1E+07 1.9E+27 4.2E-04 2.5E+01 2.2E-15 8.8E-17
Neutron Star 1.0E+04 4.0E+30 5.0E+10 2.7E+12 1.9E+03 7.0E-10
Magnetar 1.0E+04 4.0E+30 2.0E+11 2.7E+12 7.6E+03 2.8E-09


So even for a Magnetar (see also 1, 2) a kind of neutron star with a very strong magnetic field), the magnetic force on our 1kg specimen of permanent magnet is only 3 parts per billion as strong as the gravitational force.



You might see a much more favorable ratio if you compared two subatomic particles at short ranges (e.g. 1E-15 meters) but for astronomical objects, gravity seems to win smartly.






share|improve this answer











$endgroup$



Let's look at the proper magnetic force (as opposed to the Lorentz force on a moving, charged object described in @KenG's answer) on a specimen $S$ of magnetized material with mass $M_S$ as a way to try to compare. Let's arbitrarily assume it has a fixed, permanent magnetic moment $m_S$. We can't use iron because it will saturate too easily.



Then let's look at how the forces scale differently with distance



$$mathbfF_G = -fracG M_S Mr^2mathbfhatr tag1$$



$$mathbfF_B =nabla (mathbfm_S cdot mathbfB(mathbfr)) tag2$$



If we reduce these to scalar equations at a radius $R$ (assume $mathbfm_S$ and $mathbfB$ are parallel) assume all forces are attractive, and evaluate the potentials and their gradients on the equator of the body at it's physical radius $R$. Since the magnetic force on our dipole specimen drops off faster than the gravitational force, we have to evaluate the two at the closest physically possible distance:



$$F_G = fracG M_S MR^2 tag3$$



$$F_B = frac3 m_S B_r=RR tag4$$



where our specimen is a distance $R$ from our field source, and it's moment $m_S$ is a magnetization of 1 Tesla times the volume of a 1 kg rare earth magnet, about 0.000125 cubic meters.



All MKS units, all rough, ballpark numbers with emphasis on strongest magnetic fields



Body R (m) M (kg) B(r=R) (T) F_G (N) F_B (N) F_B/F_G
Earth 6.4E+06 6.0E+24 5.0E-05 9.8E+00 2.9E-15 3.0E-16
Jupiter 7.1E+07 1.9E+27 4.2E-04 2.5E+01 2.2E-15 8.8E-17
Neutron Star 1.0E+04 4.0E+30 5.0E+10 2.7E+12 1.9E+03 7.0E-10
Magnetar 1.0E+04 4.0E+30 2.0E+11 2.7E+12 7.6E+03 2.8E-09


So even for a Magnetar (see also 1, 2) a kind of neutron star with a very strong magnetic field), the magnetic force on our 1kg specimen of permanent magnet is only 3 parts per billion as strong as the gravitational force.



You might see a much more favorable ratio if you compared two subatomic particles at short ranges (e.g. 1E-15 meters) but for astronomical objects, gravity seems to win smartly.







share|improve this answer














share|improve this answer



share|improve this answer








edited May 31 at 7:51

























answered May 30 at 4:40









uhohuhoh

8,95922581




8,95922581











  • $begingroup$
    I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
    $endgroup$
    – Rob Jeffries
    May 31 at 7:45










  • $begingroup$
    @RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
    $endgroup$
    – uhoh
    May 31 at 7:48











  • $begingroup$
    Comments are not for extended discussion; this conversation has been moved to chat.
    $endgroup$
    – called2voyage
    Jun 1 at 22:52
















  • $begingroup$
    I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
    $endgroup$
    – Rob Jeffries
    May 31 at 7:45










  • $begingroup$
    @RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
    $endgroup$
    – uhoh
    May 31 at 7:48











  • $begingroup$
    Comments are not for extended discussion; this conversation has been moved to chat.
    $endgroup$
    – called2voyage
    Jun 1 at 22:52















$begingroup$
I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
$endgroup$
– Rob Jeffries
May 31 at 7:45




$begingroup$
I don't think your expression for magnetic force is correct. For a magnetic material it should depend on $B^2$. And if you are putting in $G$ and using SI units, then where is the $mu_0/4pi$?
$endgroup$
– Rob Jeffries
May 31 at 7:45












$begingroup$
@RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
$endgroup$
– uhoh
May 31 at 7:48





$begingroup$
@RobJeffries the word "magnetic" is an artifact from a previous version and I'll change it to "magnetized". The next sentence states that it's a permanent magnet with magnetic moment $mathbfm_S$ (1 kg, density of about 8000 kg/m^2, 1 Tesla magnetization) and later I mention that we can assume $mathbfm_S$ and $B$ to be parallel (or antiparallel) It's of course preposterous to put a magnet near the surface of a neutron star (unless it's in a General Products hull). I just want to show that gravity wins by a landslide.
$endgroup$
– uhoh
May 31 at 7:48













$begingroup$
Comments are not for extended discussion; this conversation has been moved to chat.
$endgroup$
– called2voyage
Jun 1 at 22:52




$begingroup$
Comments are not for extended discussion; this conversation has been moved to chat.
$endgroup$
– called2voyage
Jun 1 at 22:52











36





+50







$begingroup$

It depends on what object it's acting on. There are many objects, including stars, that have magnetic fields where Lorentz forces on charged particles like electrons and protons are stronger than the gravitational force on them.



Also remember that the strength of the Lorentz force depends on the speed of the particle moving through it, so a fast enough moving electron even here on Earth will receive a larger magnetic force than a force of gravity. This is how the Earth's magnetic field is able to contain charged particles in the Van Allen belts that its gravity could not contain.






share|improve this answer











$endgroup$








  • 1




    $begingroup$
    Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
    $endgroup$
    – uhoh
    May 30 at 4:55







  • 1




    $begingroup$
    Nice answer to a somehow ill posed question
    $endgroup$
    – Alchimista
    May 30 at 9:35






  • 1




    $begingroup$
    +1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
    $endgroup$
    – Mindwin
    May 30 at 12:38






  • 1




    $begingroup$
    @Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
    $endgroup$
    – Mindwin
    May 30 at 12:40






  • 1




    $begingroup$
    @Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
    $endgroup$
    – Muze
    May 30 at 23:08















36





+50







$begingroup$

It depends on what object it's acting on. There are many objects, including stars, that have magnetic fields where Lorentz forces on charged particles like electrons and protons are stronger than the gravitational force on them.



Also remember that the strength of the Lorentz force depends on the speed of the particle moving through it, so a fast enough moving electron even here on Earth will receive a larger magnetic force than a force of gravity. This is how the Earth's magnetic field is able to contain charged particles in the Van Allen belts that its gravity could not contain.






share|improve this answer











$endgroup$








  • 1




    $begingroup$
    Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
    $endgroup$
    – uhoh
    May 30 at 4:55







  • 1




    $begingroup$
    Nice answer to a somehow ill posed question
    $endgroup$
    – Alchimista
    May 30 at 9:35






  • 1




    $begingroup$
    +1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
    $endgroup$
    – Mindwin
    May 30 at 12:38






  • 1




    $begingroup$
    @Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
    $endgroup$
    – Mindwin
    May 30 at 12:40






  • 1




    $begingroup$
    @Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
    $endgroup$
    – Muze
    May 30 at 23:08













36





+50







36





+50



36




+50



$begingroup$

It depends on what object it's acting on. There are many objects, including stars, that have magnetic fields where Lorentz forces on charged particles like electrons and protons are stronger than the gravitational force on them.



Also remember that the strength of the Lorentz force depends on the speed of the particle moving through it, so a fast enough moving electron even here on Earth will receive a larger magnetic force than a force of gravity. This is how the Earth's magnetic field is able to contain charged particles in the Van Allen belts that its gravity could not contain.






share|improve this answer











$endgroup$



It depends on what object it's acting on. There are many objects, including stars, that have magnetic fields where Lorentz forces on charged particles like electrons and protons are stronger than the gravitational force on them.



Also remember that the strength of the Lorentz force depends on the speed of the particle moving through it, so a fast enough moving electron even here on Earth will receive a larger magnetic force than a force of gravity. This is how the Earth's magnetic field is able to contain charged particles in the Van Allen belts that its gravity could not contain.







share|improve this answer














share|improve this answer



share|improve this answer








edited May 30 at 4:44









uhoh

8,95922581




8,95922581










answered May 30 at 0:49









Ken GKen G

4,5731716




4,5731716







  • 1




    $begingroup$
    Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
    $endgroup$
    – uhoh
    May 30 at 4:55







  • 1




    $begingroup$
    Nice answer to a somehow ill posed question
    $endgroup$
    – Alchimista
    May 30 at 9:35






  • 1




    $begingroup$
    +1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
    $endgroup$
    – Mindwin
    May 30 at 12:38






  • 1




    $begingroup$
    @Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
    $endgroup$
    – Mindwin
    May 30 at 12:40






  • 1




    $begingroup$
    @Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
    $endgroup$
    – Muze
    May 30 at 23:08












  • 1




    $begingroup$
    Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
    $endgroup$
    – uhoh
    May 30 at 4:55







  • 1




    $begingroup$
    Nice answer to a somehow ill posed question
    $endgroup$
    – Alchimista
    May 30 at 9:35






  • 1




    $begingroup$
    +1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
    $endgroup$
    – Mindwin
    May 30 at 12:38






  • 1




    $begingroup$
    @Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
    $endgroup$
    – Mindwin
    May 30 at 12:40






  • 1




    $begingroup$
    @Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
    $endgroup$
    – Muze
    May 30 at 23:08







1




1




$begingroup$
Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
$endgroup$
– uhoh
May 30 at 4:55





$begingroup$
Excellent! +1 I totally forgot about the Lorentz force experienced by charged particles and just did plain old static magnetic force versus gravitational force.
$endgroup$
– uhoh
May 30 at 4:55





1




1




$begingroup$
Nice answer to a somehow ill posed question
$endgroup$
– Alchimista
May 30 at 9:35




$begingroup$
Nice answer to a somehow ill posed question
$endgroup$
– Alchimista
May 30 at 9:35




1




1




$begingroup$
+1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
$endgroup$
– Mindwin
May 30 at 12:38




$begingroup$
+1 also for pointing out the big difference. Gravity is unaffected by (discrete || <<< c) speed while Lorentz force is.
$endgroup$
– Mindwin
May 30 at 12:38




1




1




$begingroup$
@Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
$endgroup$
– Mindwin
May 30 at 12:40




$begingroup$
@Alchimista That is the Pearls >>> Sand the Stack runs on. Scoop the bottom of the ocean. Questions are like sand but the scooped section may contain pearls somewhere. A question can be measured by the quality of the answers it sparked.
$endgroup$
– Mindwin
May 30 at 12:40




1




1




$begingroup$
@Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
$endgroup$
– Muze
May 30 at 23:08




$begingroup$
@Mindwin Thank You very much. I actually put much thought in the question. How would you word it?
$endgroup$
– Muze
May 30 at 23:08











9












$begingroup$

It isn't impossible, but the short answer is "no".



A gravitational field will accelerate all matter and energy equally while a magnetic field will only accelerate moving electric charges (other magnets).



The force due to gravity is proportional to the inverse square of the distance, and the force due to magnetism asymptotically approaches the inverse cube of the distance. At some critical distance the gravitational force will become stronger than the magnetic force.



Unless most of the large body was magnetic, even over the magnetic poles the magnetic field would probably be too low to levitate a typical magnet in the large body's gravitational field.






share|improve this answer









$endgroup$








  • 1




    $begingroup$
    Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
    $endgroup$
    – uhoh
    May 30 at 22:49











  • $begingroup$
    Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
    $endgroup$
    – PERFESSER CREEK-WATER
    Jun 4 at 19:11










  • $begingroup$
    Still here? just wandering?
    $endgroup$
    – Muze
    Jun 5 at 1:04















9












$begingroup$

It isn't impossible, but the short answer is "no".



A gravitational field will accelerate all matter and energy equally while a magnetic field will only accelerate moving electric charges (other magnets).



The force due to gravity is proportional to the inverse square of the distance, and the force due to magnetism asymptotically approaches the inverse cube of the distance. At some critical distance the gravitational force will become stronger than the magnetic force.



Unless most of the large body was magnetic, even over the magnetic poles the magnetic field would probably be too low to levitate a typical magnet in the large body's gravitational field.






share|improve this answer









$endgroup$








  • 1




    $begingroup$
    Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
    $endgroup$
    – uhoh
    May 30 at 22:49











  • $begingroup$
    Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
    $endgroup$
    – PERFESSER CREEK-WATER
    Jun 4 at 19:11










  • $begingroup$
    Still here? just wandering?
    $endgroup$
    – Muze
    Jun 5 at 1:04













9












9








9





$begingroup$

It isn't impossible, but the short answer is "no".



A gravitational field will accelerate all matter and energy equally while a magnetic field will only accelerate moving electric charges (other magnets).



The force due to gravity is proportional to the inverse square of the distance, and the force due to magnetism asymptotically approaches the inverse cube of the distance. At some critical distance the gravitational force will become stronger than the magnetic force.



Unless most of the large body was magnetic, even over the magnetic poles the magnetic field would probably be too low to levitate a typical magnet in the large body's gravitational field.






share|improve this answer









$endgroup$



It isn't impossible, but the short answer is "no".



A gravitational field will accelerate all matter and energy equally while a magnetic field will only accelerate moving electric charges (other magnets).



The force due to gravity is proportional to the inverse square of the distance, and the force due to magnetism asymptotically approaches the inverse cube of the distance. At some critical distance the gravitational force will become stronger than the magnetic force.



Unless most of the large body was magnetic, even over the magnetic poles the magnetic field would probably be too low to levitate a typical magnet in the large body's gravitational field.







share|improve this answer












share|improve this answer



share|improve this answer










answered May 30 at 20:43









anonymousanonymous

911




911







  • 1




    $begingroup$
    Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
    $endgroup$
    – uhoh
    May 30 at 22:49











  • $begingroup$
    Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
    $endgroup$
    – PERFESSER CREEK-WATER
    Jun 4 at 19:11










  • $begingroup$
    Still here? just wandering?
    $endgroup$
    – Muze
    Jun 5 at 1:04












  • 1




    $begingroup$
    Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
    $endgroup$
    – uhoh
    May 30 at 22:49











  • $begingroup$
    Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
    $endgroup$
    – PERFESSER CREEK-WATER
    Jun 4 at 19:11










  • $begingroup$
    Still here? just wandering?
    $endgroup$
    – Muze
    Jun 5 at 1:04







1




1




$begingroup$
Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
$endgroup$
– uhoh
May 30 at 22:49





$begingroup$
Electrons have large magnetic moments and small mass, so there might be a chance for them, and ortho-positronium has a magnetic moment, small mass, and is uncharged so there wouldn't be any Lorentz force.
$endgroup$
– uhoh
May 30 at 22:49













$begingroup$
Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
$endgroup$
– PERFESSER CREEK-WATER
Jun 4 at 19:11




$begingroup$
Excellent comment. Bottom line is that magnetic forces exceed gravitational forces only if the object is tiny, such as an electron or an atom.
$endgroup$
– PERFESSER CREEK-WATER
Jun 4 at 19:11












$begingroup$
Still here? just wandering?
$endgroup$
– Muze
Jun 5 at 1:04




$begingroup$
Still here? just wandering?
$endgroup$
– Muze
Jun 5 at 1:04

















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