Martian Auroras
Aug 19, 2009

Terrestrial auroras are thought to be generated when the Earth’s magnetic field deflects solar wind particles to the magnetic poles. The particles are somehow accelerated along magnetic field lines, and when the lines dive toward the surface, the particles collide with atoms in the atmosphere, causing the atoms to emit light.

Indications of thousands of aurora events turned up in a review of space probe data. Reviewers constructed a map of occurrences and found that they clustered around the margins of magnetic patches on the surface. The patches are thought to be crustal rocks that have preserved magnetic fields acquired from an ancient global field that has decayed. Why they occur almost entirely in the southern hemisphere is not understood.

Theorists speculate that the solar magnetic field lines, which are thought to be “frozen” into the solar wind, “break” and reconnect to the crustal field lines, “flinging” electrons to high energies. It’s “a physical process still not understood.”

Astronomers might begin to understand if they did some homework in the pages of the plasma science journals. Magnetic field lines are symbolic representations of what in reality is a continuous measure of magnetic force. The lines are a convention to indicate the direction of the force at each point in space, and their spacing indicates the strength. But the lines, being imaginary constructs, cannot “freeze” or break or reconnect or “fling” anything. Attributing actions to imaginary constructs is a lazy excuse for failing to describe actual mechanisms that, in this case, have already been described by others.

Charged particles streaming in the same direction as the magnetic field constitute “field aligned currents,” or Birkeland currents, named after the Norwegian scientist who, in the late 19th century, first proposed their existence as the cause of auroras. Birkeland currents generate “double layers” along their paths as the current fluctuates. Double layers are regions of electrostatic charge separation maintained by the forces in the current. Strong electric fields build up between the layers, and charged particles that flow into these regions are accelerated to high energies.

It’s no wonder astronomers fail to understand: they have reversed cause (electric currents) and effect (magnetic fields), they have denied the existence or downplayed the importance of the electrical processes, and they have asked the wrong questions. The magnetism in the patches is reinforced by, if not entirely generated by, the current channels that enclose the patches. Because a persistent current must be part of a larger circuit, astronomers should be asking why the currents are especially strong in the southern hemisphere, and where do they go. Where’s the rest of the circuit?

The Electric Universe suggests that the answer likely has something to do with the different planetary configuration indicated by the cosmogonic stories of prehistoric peoples. Common themes and images found in ancient cultures around the globe point to electrical interactions between Earth and Mars, in which Earth’s northern polar region and Mars’s southern polar region were swept by an electrical vortex similar to what may be seen today, at much higher energies, in the penumbras of sunspots.

It’s likely that crustal rocks from Earth could be electrically deposited on Mars and heated. If they cooled below the Curie point before the current and its accompanying magnetic field completely decayed, they would retain the magnetism. Since Mars has no global magnetic field in which the spots would appear merely as local deflections, they stand out as foci for aurora events.

Mel Acheson