There are many people who believe in astrology and read their daily horoscopes avidly, and there are many who dismiss the idea completely. What's the truth? Bear along with me as we explore� a few� novel aspects.

Being trained in Physics and Oceanography, I was for many years dismissive of astrology, and still am, in the conventional sense. I cannot buy into the proposition that there are 12 basic personalities defined by one's starsign.

We know that the tides are governed mainly by the moon and sun (though there are several hundred terms in the equation which is used for tidal prediction). Bear in mind that the earth itself, and the atmosphere also experience tides - not only the sea has tides. That is the first aspect.

I suffer with seasonal affective disorder (�SAD'), and have done so for about 20 years. This disorder is caused by the seasonal variation in sunlight level and intensity in people who live outside the tropics. It is a depressive disorder, and by definition, seasonal in nature. In its most severe form it is known as bipolar disorder.

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The underlying mechanism is related to the body's production of serotonin and melatonin. For me, this leads to the idea that behaviour (governed by mood), can be influenced by seasonal sunlight levels. That is my second aspect.

There is a book called �Outliers', by Malcolm Gladwell (he also wrote �Tipping Point'). A fascinating read, but I'll pick out just one of his propositions. He analyses the birthdays of the star players of NFL teams (that's American Football). The star players tend to have birthdays at a particular time of year.

No, not Astrology. Players born early in the year tend to be the oldest in their school/college peer group. Therefore, they are more mature physically than other students in their school year born later in the year. If there is 11 months difference in birthdays between oldest and youngest in a given school year, then at age 12, say, there is 7-8% difference in physical maturity. The older and stronger students then tend to excel in their school year as compared with their peer group and so get more encouragement and support, and so on, self reinforcing. That's my third aspect.

Let us try and pull these aspects together:

- the earth, oceans and atmosphere are subject to astronomical forces (tides).

- Outside the tropics, a propensity for part of the population (SAD sufferers ~17%) to be affected by seasonal sunlight levels (just a result of the earth's orbit around the sun), via a mechanism which alters body chemistry. Also the human female menstrual cycle is tied generally to the lunar orbital period (though obviously not all women are in phase).

- Segments of the population exist whose physical ability and success is determined by the time of year at which they were born. This could be tested by looking at countries where academic years differ (Malcolm Gladwell explored this, but only in the context of the extent of summer vacation length, East versus West).

We could reasonably expect that the effects of the �birth at time of year' might be visible in academic prowess (as opposed to sporting prowess), though surely the education profession would have detected this by now.

Might we be seeing, at least at a first order level, effects on the population and individual personality arising from the earth's motion around the sun, and moon around the earth? I am sure we are. There is probably a lot more to this than we can pick up here, but food for thought is it not?

How do Astrology and Starsigns fit in? Could they be a proxy for this set of effects arising from the planetary motion of the Earth and the Moon? However, I can't believe that lower order effects (such as Uranus in Scorpio) would be significant at all.

Nevertheless, it is in the nature of human beings to refine ideas and systems. Maybe it is not snake oil after all.

�© 2009 Pete Marsh. All Rights Reserved

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