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The electric force cancels over short distances. Magnetic force may act over multi-light-year distances, as may be easily seen in the turbulent flow of luminous

The electric force cancels over short distances. Magnetic force may act over multi-light-year distances, as may be easily seen in the turbulent flow of luminous plasma visible near supernova remnants, supermassive black holes, and in star-forming regions. Turbulent flow of neutral gases at such pressure and scale is impossible because collisions are too infrequent.

pdonis 3y ago
> Magnetic force may act over multi-light-year distances, as may be easily seen in the turbulent flow of luminous plasma The plasma itself is magnetic, so the magnetic force itself is not acting over multi-light-year distances; the material carrying the magnetism is traveling over those distances and bringing its magnetism with it. Also, this magnetism doesn't affect the orbits of planets or stars; my original statement was focused on what affects those things.
- angiosperm 3y ago
  And, that material's magnetism is interacting with magnetism carried by other material. Turbulently. And affecting the motion of all the material.
  - jvanderbot 3y ago
    I agree with GP, the measurable effects of the magnetic field are not strong, it's just that they're close because charged particles carried them close. Maybe a better electromagnetic example would be radio signals from pulsars, which are enormous and travel great distances and still provide measurable signals even if they are light years away. We cannot on earth measure the gravity of these objects, nor the atomic forces, but we can readily meausure their electromagnetic sprayings.
    - angiosperm 3y ago
      Yet, nearly all of the extended structure of luminous interstellar gas we see in the best pics on APOD is the plasma fluid interaction that astrronomers can't be bothered about. SOFIA could have revealed much, if not grounded. Are any of the new orbital telescopes about to come online equipped to record polarization?

pdonis 3y ago

> Magnetic force may act over multi-light-year distances, as may be easily seen in the turbulent flow of luminous plasma The plasma itself is magnetic, so the magnetic force itself is not acting over multi-light-year distances; the material carrying the magnetism is traveling over those distances and bringing its magnetism with it. Also, this magnetism doesn't affect the orbits of planets or stars; my original statement was focused on what affects those things.

angiosperm 3y ago
And, that material's magnetism is interacting with magnetism carried by other material. Turbulently. And affecting the motion of all the material.
- jvanderbot 3y ago
  I agree with GP, the measurable effects of the magnetic field are not strong, it's just that they're close because charged particles carried them close. Maybe a better electromagnetic example would be radio signals from pulsars, which are enormous and travel great distances and still provide measurable signals even if they are light years away. We cannot on earth measure the gravity of these objects, nor the atomic forces, but we can readily meausure their electromagnetic sprayings.
  - angiosperm 3y ago
    Yet, nearly all of the extended structure of luminous interstellar gas we see in the best pics on APOD is the plasma fluid interaction that astrronomers can't be bothered about. SOFIA could have revealed much, if not grounded. Are any of the new orbital telescopes about to come online equipped to record polarization?