The sun created life on earth and made the earth green. It drives the seasons and keeps the earth warm. It created human beings, actually shaped us from the matter of the earth. It radiates enough energy each second to supply all present human energy needs for a million years. No god conceived by the solar-powered human imagination, nor inspired by holy books or Steven Spielberg movies, compares in physical size and power to the object that daily traverses the sky and drives the world, and from whose divine gaze we avert our eyes in practical reverence. The sun has the thermonuclear wherewithal to keep things going for at least another billion years.
From my notes: December 28, 2007 — Benazir Bhutto, a former Prime Minister of Pakistan, was assassinated yesterday morning, ~1100 hours EST. In one of those quirks of the associative mind, her death evokes a memory of the Archduke Franz Ferdinand of Austria, assassinated in Sarajevo, June 28,1914. The initial associative linkage, assassination of a political figure, will be reinforced if a major war follows Bhutto's death. In the Archduke's time, people hadn't yet figured out how to release the binding energy of heavy atomic nuclei.
Elsewhere in news that day: In a review of a biography in the latest issue (January 17, 2008) of The New York Review of Books, the British physicist Freeman Dyson reports that rocketman Wernher von Braun didn't really have his heart in the Nazi thing, that the SS uniform was embarrassing, and that von Braun became a born-again Christian in 1946. A friend invited me out to dinner, to get my agreement on his plan to kill his 95-year-old mother with an overdose of morphine. The Russian government banned a television advertisement denying the existence of Father Christmas; the Queen of England got an Internet channel; a report published in Nature says that the stimulation of a single neuron in a rat brain can cause the sensation of touch; the heiress of the Hilton Hotel fortune might not inherit the wealth; and so on . . .
There is an endless supply of stories on this naked planet, all of them associatively linked in one way: They are solar-powered by light from the local star, starlight, sunlight.
During the noon hour on a hot summer day, the incoming solar energy to my 5,000-square-foot lot amounts to nearly 700 horsepower. That much power would cost about ~$75 an hour if I got it from the local power company.
Energy is all-important. It is food. It is what drives the world, makes everything move, wind, weather, getting to work, having a good time, staging a war, getting laid.
The 700-Megaton Man
Money is a standard cultural way to think about all-important energy, which is why money itself is also all-important. Money is an energy-accounting method. Money = Energy. Different words meaning the same thing. The equivalence of money and energy can be calculated on the basis of the cost of gasoline, natural gas, or the wholesale or retail cost of electricity. It could also be figured in terms of the food energy in bananas, apples, beef or celery.
Assume Bill Gates is worth $50-billion. Using the wholesale cost of electricity as the money/energy exchange rate, Bill Gates is equivalent to [8.33E11 kWh; 3E18 Joules] nearly 60,000 Hiroshima bombs worth of energy or about 700 megatons of TNT equivalent. Personal wealth can be rendered this way.
Money and Space
People say, "Well, what's the point of going to the moon, or what's the point of human beings being in space? What's it get us to go to the moon?"
Well, ultimately, it's the money — which is to say, it's the energy.
The value of the solar energy that shines onto the moon is [1.28E16 watts] $200 million/second, if the wholesale price of electric energy is the basis. A year of sunlight hitting the moon equals all present human energy needs for a thousand years. Someday someone might yet harvest it, and make current measures of wealth look trivial and stupid.[insert link to Energy and the Reverend Mr. Malthus.]
The latter half of the twentieth century has seen the greatest Golden Age in human experience, in terms of comfort and general welfare for the largest number of human beings. If a cause is to be attributed, the low cost of energy from coal and oil must certainly be it. Someday that supply is going to run out.
A Shoreline-Crossing Precedent
In the olden days — which is to say, like back during the first three billion years of life on this planet — our ancestors lived in the sea, and the dry land was sterile. Then they crossed the shoreline between the sea and the hostile dry land and got the benefit of more direct access to sunlight. They adapted to the hot, hostile and dry scene, and with greater access to sunlight, they made the earth into a blue-green Eden. Now, only 450-million years later, the biological range of life has already, in a tentative way, crossed the shoreline separating dry land from space.
The migration of life from the seas to the dry land is a precedent for one possible future for human beings and the life of earth.
What follows here assumes that living on other planets in the solar system is impractical, because the material in the planets, like the energy wealth flowing from the sun, is also a source of astronomical wealth. [insert link to #200-billion under my house; also to Japanese Cars from the Moon]
The Next Thousand Years
Within the next thousand years, barring a show-stopping calamity, human beings will use nuclear and thermonuclear energy and sunlight to drive the mining of aluminum, titanium and silicon on the moon. Huge artificial planets (>100,000-ton, aircraft-carrier size) will be built on the moon and pushed into solar orbit. Each might carry a million people, or more. Each will be mostly self-sustaining. Some will be individual "planet-states." Others will form alliances of planet-states. They will carry on inter-"planetary" trade with one another. Business as usual, in short — though humanity will gain new insights into the processes that arise when what we call "base matter" is energized by the light of a star.
Trade among artificial planet-states will be driven by antimatter-powered vehicles for timely delivery of goods. [insert link to Interplanetary pizza delivery.] Slower deliveries will be managed by electromagnetic launch methods, rail-guns and the like, wherein delivery times would be on the order of months to centuries.
In space, there are no natural time-keeping rhythms equivalent to days, seasons, and years, so an artificial system will be needed. The time-keeping system will also operate as a real-time mapping system for the entire space-based biological domain of life from earth.[insert link to Metric Clock/Calendar]
The Next Ten-Thousand Years
Within ten-thousand years, the solar system will be swarming with billions of artificial planets — each in its way equivalent to a sun-powered lifeform that will stand in relation to us individual humans as we stand in relation to our bacterial ancestors.
The Next Few Million Years
Over the next few million years, the inner planets will be cut up for materials from which to add to the size and power of the [insert link to Dyson Sphere according to Freeman Dyson] around the sun, from which energy will be collected and sold and traded and fought over in the expansion of the range of life from earth. (The present-day notion of "geologic time" will become irrelevant as the earth is mined deeper and deeper into its valuable iron core.[insert link to Mining the Earth to its Core])
In the 400-million years or so since our ancestors came out of the sea, the surface of the earth has been transformed into a green place that is still beautiful to see and think about — despite the growing fleets of SUVs and intercontinental bombers. In the future, a corresponding solar-driven transformation of the entire solar system will create a correspondingly beautiful new setting, one from which exploration vehicles — in the role of seeds — will be launched outward toward other stars. At the very least, with a solar-system sized telescopic aperture, we will be able to see pretty clearly to within a few light-centuries of the edge of the observable universe — assuming that that present-day paradigmatic view still holds in a million years — or even in ten years . . .
In fewer than a million years, a trillion cubic astronomical units (AUs) of space will be filled with "multi-color" microwaves that will be coded with time signals and able to track the locations and velocities of all material objects larger than a few millimeters in characteristic dimension.
The Next Billion Years or So
In a billion years, at most, all of what we now call "the planets" will have been reshaped by sunlight — through the solar-agency of technological creatures such as ourselves — into a meta-arrangement of matter that will be equivalent, in a way, to the corals that have amassed trillions of tons of carbonate into their own structures. Sun-made life from earth will have eaten the planets.
By the time the sun begins to run out of fuel and expand to a million times its present volume, the descendants of present life on earth will inhabit a stupendous volume of space and be relatively safe from such things as "solar transients" of the sort that now have the theoretical potential to wipe us out in our present still-young age. For those who might be sentimental about the material of Mother Earth, most of it will have been carried beyond the reach of the expanding sun, rather than being absorbed into it.
One final point: The solar wind will blow outward for several billion more years. It will, as it does now, evaporate matter from the planets into interstellar space. (Atoms that were once part of me and everyone I know, or, for that matter, everyone who has ever existed, are already traveling in interstellar space, having been knocked from the upper atmosphere by the impacts of solar-wind particles and the force of sunlight.) Thus, in a billion years or so, an increasingly precious commodity will be raw matter itself. At that point, life from earth will have to consider migrating to other stars, ones having the traditional necessities of life, which are matter and energy, and space in which to grow and access to the starlight that activates matter into the kinds of self-aware endeavors of the sort that make the likes of thought and imagination possible, as well as the inevitable creation of such twisted shapes of matter that forever cause trouble, and keep us nimble.
[A variation of this essay was published in the August/September, 2010, issue of Free Inquiry, entitled "Energy and the Human Far Future." The next billion years or so, Dyson Spheres and things like that. Check it out.]