What is Magnetism's role in the universe?

Many of us have played with magnets and noted how if you try to hold two magnets so that similar poles are close they repel, and if the poles are opposite they attract. The Earth also has a magnetic field that protects us from the solar wind and flare eruptions from the Sun. Without it we would not be here. Many planets, especially the gas giants, have magnetic fields. Jupiter has an enormous magnetic field as evidenced by strong auroras.

How does magnetism work? Listen to this, gang! It's called electromagnetism, and it works by electrons and protons in atoms exchanging short-lived photons. This photon exchange is crazy action on the quantum level. When you hold two magnets with opposite poles, this is how they attract; they exchange photons back and forth as a means of providing magnetic force. That's how magnetism works. And, if it weren't for electromagnetism, our atoms, and the atoms of everything, would fly apart. We would disintegrate, the Earth would fly apart and chaos would reign. Electromagnetism is fundamental to the structure of everything in the universe, including us.

There is a lot of magnetism out there in the universe, and it's only been recently that scientists have begun to realize what role magnetism plays in the universe.

Our solar system formed because of gravity. A gas and dust cloud from a supernova explosion began to condense because of gravity into a more concentrated ball of gas. However, angular momentum made the dust and gas cloud rotate, and as the rotational velocity increased the accretion disc flattened into a spiral. This would have prevented star formation if it weren't for magnetism. As the accretion disc rotated, it created magnetic fields that slowed the disc's velocity. This allowed more gas to fall into the center and ultimately begin to fuse. Without magnetism, star formation would not have occurred.

Magnetism is everywhere. The Sun has a huge magnetic field and the Milky Way galaxy is full of magnetism. In fact, magnetism is what shaped our galaxy in the first place. When large stars explode in a supernova, the expanding gas cloud that results collides with charged plasma in the galaxy. This is noted as a brightening of the glow in the cloud's leading edge as it expands. What's happening here is that the gas cloud is being influenced by a strong magnetic field that pervades the galaxy.

When our Milky Way galaxy formed some 12 to 13 billion years ago it was just a large spherical group of stars brought together by gravity. But, it was large enough to begin spinning and that formed it into a spiral structure because of the conservation of angular momentum. Magnetism also played a role in the formation of the galaxy's shape. The spinning motion caused charged plasma to create magnetic fields that spiraled out like a pinwheel. Stars formed along these magnetic lines because the magnetic field provided an impetus to compress gas into stars. These magnetic lines acted as a cosmic superhighway for star formation.

However, this magnetic field effect also prevented more of the outer halo gas that surrounds the galaxy form being formed into stars. Astronomers believe that there should be many more stars in our galaxy, and they had trouble realizing why until just recently. This magnetic effect in the outer arms of the galaxy prevented star formation by repelling the gas' charged gas particles. That might have been a lucky deal for us because it could have prevented our Sun from having a neighboring star. A binary system could have upset the formation of the solar system as we see it now. We owe our existence to this galaxy magnetism.

Magnetism in the cosmos is often very strong, in some cases millions and billions of times the magnetic field around the Earth. These strong fields are associated with neutron stars and especially magnetars, the most magnetic object in the universe. Magnetars rotate fast and the twisting magnetic fields are responsible for some very bizarre behavior. If you approached such an object even at thousands of miles, the iron in your blood would be ripped out of your body. In fact all of your atoms would be torn apart.

On December 7, 2004, the Earth was bombarded with a massive blast of radiation. This came from a magnetar 50,000 light years away and the force of the blast actually blew some of the upper atmosphere away. No one even noticed it, but it happened. If this magnetar had been much closer, the atmosphere would have been blasted off completely. This incident occurred because a crack in the magnetar's surface caused a star quake that disrupted the magnetic fields of the magnetar, causing it to emit a huge blast of radiation like a gamma ray burst. Wow!

However, the Milky Way's overall magnetic field is very weak compared to the Earth's field. This type of magnetic field is evidenced in many galaxies in the universe. The recordings of radio telescopes show us all of this because gas clouds heated by magnetism emit radio waves. The stronger the radio waves, the more magnetism that is responsible. Magnetic fields from stars fill the cosmos and often affect how cosmic rays and other radiation is distributed in the universe. The Sun's magnetic field at the edge of our solar system protects us from cosmic radiation. Voyager I found this effect when it reached the edge of the Sun's hemisphere.

Much of the magnetism in the Milky Way galaxy is caused by the shock wave effect of the supernovae remnants smashing into interstellar gas clouds in space and the rusultant mixing causes magnetic fields.

Overstuffed supermassive black holes emit beams of energetic particles and radiation (Quasars) and they also smash into interstellar gas clouds to produce magnetic fields.

Obviously, the entire universe's structure has been influenced by magnetic fields. Magnetism is a force that cannot be ignored, and it has played a vital role in our existence.

Thanks for reading.