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The Pilot, Page 11

solarsalvage

on May 15, 2011

Fluxin’ magnetospheres, how do they work?

A magnetic field results from any charged particle in motion.
A planetary magnetic field is extraordinarily large and long-lived. It's called a magnetosphere and is thought to be produced by electrically conductive metals in motion, according to dynamo theory.

The Earth has one due to its core of iron and nickel that is swirling and churning due the the heat and pressure therein.

This produces a magnetic field circling the entire planet, and this is a good thing. This field repels plasma: protons and electrons stripped away from atoms.

This plasma is what makes up the Solar Wind, a mass of particles constantly streaming from the Sun's nuclear furnace. Without a shield against this wind, the Earth?s atmosphere would eventually blow away, turning it into a barren, all-but-airless rock, like Mars.

But fortunately, we have a planetary dynamo, and thus, a safe place for life to grow.

But there's a dark side to our magnetosphere. Ions that get through it become trapped, forming radiation belts capable of thoroughly frying anyone who crosses them.

Earth's is made up of bits of the Solar Wind that get through and its own atmosphere, ionized by cosmic rays. This produces a negatively-charged outer belt and a positively-charged inner belt. Either one of these can kill, but between them is a narrow zone, which a carefully piloted spacecraft might safely travel.

Yet the Earth?s magnetosphere is relatively tame. Jupiter's is terrifying. Driven by a massive, seething ocean of liquid metallic hydrogen, it is over a thousand times more powerful than Earth's.

If Jupiter's magnetosphere were visible, it would appear from Earth as larger than the moon. Extending as far out as the orbit of Saturn, and is large enough to contain the Sun itself.

As such, it has radiation belts of immense proportions, which are constantly fed with ions from its volcanic moons, resulting in massive bands of death encircling the entire planet. Even shielded robotic probes can become disabled if they fall too far into these fields.

A good thing on Earth becomes a very bad thing on Jupiter.

Thus, to successfully sustain life, moderation is key.