DEATH FROM OUTER SPACE

It is a pity that the ecofreaks cannot handle the most elementary rudiments of logic, or they would find their latest scare about radiation doses in air travel self-defeating. Yes, you do get sig-nificantly higher doses of radiation in a plane than you do on the ground; but the absence of health effects in air crews is a pretty good indication that even at elevated levels low-level radiation is harmless. And very probably it is beneficial.

The reason for the stronger background radiation in places with higher elevation (Colorado, Wyoming) let alone at altitudes of 30,000 ft and more, is the incidence of particles called cosmic rays. The primary cosmic rays are hydrogen nuclei and other particles with enormous energies, many of them moving close to the speed of light. Most of them come from outer space (at these speeds they can come into the solar system, but if unobstructed, they cannot bc captured by the sun's gravity and shoot out again along a slightly bent path). Some come from the Sun, especially during solar flares. If they are charged (electrons, positrons, mesons), the earth's magnetic field deflects them toward the poles, so that there is more of them at higher latitudes.

These primary cosmic rays never reach us, for when they hit the earth's atmosphere, they collide with the atoms of the air's gases, splitting them into fragments that shoot out and hit further atoms. The result of each primary hit is a cascade of elementary particles which eventually loses its energy as it penetrates into ever denser air. That is the reason why cosmic rays, as these particles in the descending cascade are called, get less intense (decrease in ener-gy) with decreasing altitude.

Yes, they are the same type as in the neutron bomb, and they are nothing as cozy as radioactivity: they will penetrate ten feet or more of solid earth (depending on their energy) and induce radioactivity in formerly stable material. So you can see why the dreaded gamma rays are called "soft" in comparison, and of course even the gamma rays are responsible for a far higher back-ground than on the surface. It was mainly neutrons that killed the truly heroic firemen and pilots who helicoptered into the plume at Chernobyl, and it is mainly neutrons that cause radioactive fall-out from nuclear explosions by activating originally stable atoms.

By inexorable logic it must therefore also be neutrons that cause air crews to drop dead like flies after a few flights and most pas-sengers to move from the airport straight to the morgue.

They don't?

Maybe I overlooked something.