Rational Thoughts: Unlimited

So you think the position of Mars in the sky at the time of your birth made you tall, dark, and handsome (or short, fair, and ugly)? Or lucky (or unlucky) in love? If you think believing in astrology is anywhere close to scientific, well, Dude, time to think again.

Pick two babies born within a minute of each other. One has two nurses and a doctor attending; the other, just a midwife. One is born in a brightly lit maternity ward in a downtown big city hospital; the other in a poorly lit room in a village 50 kilometers from the nearest big city. ‘Downtown’ is just a few meters above sea level; the village is situated on a 1000 meter high plateau. These local differences have far greater effects on the babies than Mars does. Let’s see how.

Nearly five centuries of physics have given us quite a few certainties, and among those are that the only long range forces in the universe are gravity and electromagnetism. And both of these, from Mars, are totally – and I mean totally – overwhelmed by those same forces that were produced by things near you when you were delivered. In a word, Mars can’t influence you.

Start with gravitation.

The gravitational force between you and Mars is greatest when Mars is closest to the Earth; let’s say that’s 56 million kilometers. Now Mars has a mass of 6.4 x 10²³ kg, so the acceleration, here on Earth, due to Martian gravity would be 1.4 x 10^-8 meters per second per second (m s^-2).

How did I work that out? By using Newton’s law of universal gravitation:
F = Gm₁m₂/r²
and:
F = ma
so:
a = Gm_Mars/distance-to-Mars².

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