As an astronomer with a research specialty in the area of the possibility of extraterrestrial life, Dr. Les Golden knows that life is fragile, that the earth may well be the only planet that exists supporting intelligent, technical life such as our own.

Man has existed in its present form, with consciousness, for only 50,000 to 100,000 of the 4.6 billion year history of the earth. That is about 1/100,000 of earth's history. This means that given 100,000 planets suitable for life, perhaps only 1 will have developed beings like us.


The question is then, how many planets suitable for life exist? The criteria are very stringent. First, the planet must be in orbit around a star like the sun. It must be a star with a relatively long lifetime, but 98% of all such stars are dim red ones, which do not provide the energy to drive biochemical processes. Half of all suitable stars, the G-type stars, are in binary pairs. These systems do not provide the kind of stable energy input amenable to the creation of life.

We are left with perhaps 1% of all stars that are suitable.

The planet must be within the "zone of habitability" of the star. It cannot be too far from the star, or its temperatures will be too cold, and not too close to the star, or its temperatures will be too hot. The zone of habitability is very narrow. In the solar system, the zone of habitability is only about 2% of its total extent.


Furthermore, this planet I believe must have a significant moon accompanying it. Without the moon, the planet will become geologically inactive, as is Mars, and without the replenishment of water and gases that geological activity provides, the planet will become biologically inactive. This is the biological history of Mars, once geologically and I believe biologically active, but now dead. Studies also show that our axis of rotation would teeter significantly, leading to unstable climates, without the moon.

Acquiring a significantly sized moon, however, is not an easy astronomical task. If other solar systems are created in a manner similar to that in which ours was formed, only massive planets such as our Jupiter, Saturn, Uranus, and Neptune have the gravitational force to attract the amounts of matter necessary for the formation of moons. For that reason, the small planets in our solar system, Mercury, Mars, and Venus lack large moons. Lunar exploration in the 1970's has now demonstrated that our moon was created by a celestial accident: A block of material collided with the nascent earth, ejecting matter that became the moon.


If everything is right -- the right type of star flying through space without a binary companion, a planet in the zone of habitability of that star, accompanied by a significant moon -- life can evolve. Will it become intelligent and conscious?

In 1 out of 100,000 times. More likely, as nature tries various experiments, it will find that size is the most important criterion for evolutionary success. The dinosaurs ruled the earth for 200 million years, and only by the chance impact of a large comet/asteroid were they extinguished, giving the tiny mammals a chance to repopulate the evolutionary niches.


Even beyond such scientific questions, what right do we have to destroy the earth? What right do we have to destroy nature's laboratory? Was not every living being on this planet created out of the same molecules as we were?

What right do we have to desecrate the earth, cut down the trees, raze the rain forests, slaughter greyhounds that are "too slow," pollute the oceans, rivers, streams, and air, extinguish the lowland gorillas?

That's the perspective a professional scientist brings to environmenal and animal rights issues.

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Links to Dr. Golden's educational background and work history as an astronomy and physics researcher and professor are on the home page.

I want to work with Dr. Golden to pass environmental and animal rights legislation

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