Tuesday, March 26, 2013

A Trip Into Space - The Far Future

Today, to end my series on space development, I will engage in some wild and speculative prognostication.

Many space enthusiasts advocate colonizing the Moon or Mars. Some of this may happen, and I have no interest in campaigning against them. However, I think that this represents a planetary bias that humans will quickly outgrow. A time will come - assuming we do not destroy ourselves - when the bulk of humanity lives - not on planets or moons - but in space.

Space provides several advantages over any planet-based community. Not the least of which is - a person can pick their gravity. I mentioned the weights on the spokes of the near-earth-orbit colony. They move in to increase the rate of spin, and out to slow the community down. Modules can be put at different lengths from the center, so that one module can have half of the gravity of another. Non-rotating modules can be attached to the hub.

Another advantage is ease of travel. Give something a gentile nudge in the right direction, and it will eventually reach its (nearby) destination. Drastically changing orbits - going from low earth to gyosynchronous orbit - will take more energy. However, it will not take nearly as much as getting into orbit from a planet's surface.

A space community has constant or near-constant sunlight - thus a near-constant source of energy.

Finally, a significant advantage of space development is the availability of much more living space. With peak efficiency, there is enough material in the asteroid belt to construct the living area equivalent of 30,000 earths. Assuming gross inefficiency, we can see a future with 1 earth, 1 Mars, and 300 earth-equivalents worth of orbiting habitats. And this ignores the material found in Jupiter's moons or comets. Planet-dwellers will be a small minority of humanity.

I am not advocating this option. I am merely predicting. At the same time, I must admit to a lot of ignorance behind this prediction. What new inventions will come our way? What will result from blending human brains with computers? I will be the first to admit that these predictions are almost certainly wrong. But, it is fun to speculate.

Where will these communities be built?

To answer this question, we need to look at what humans value as a means and as an end. Much of this value is best obtained by close proximity to others and the benefits of trade.

I expect many of these communities to be built primarily near Earth, where it occupants can communicate with Earth and others in near-Earth space, visit others, and trade with others.

A commenter to an earlier post mentioned Larry Niven's "Ringworld" around the sun. This is far-fetched. However, a "Ringworld" around the Earth - a "Tubeworld" 71,572 kilometers in diameter (over 236,000 kilometers long) represents one possible future.

There will be other communities built in the vicinity of large asteroids, where mining communities last for centuries until the asteroid is gone and the community built from it remains. The larger the asteroid, the larger the community that is left behind.

In the longer-term future, I think I can predict what star humans will colonize first.

Proxima Centauri.

Over time, people will come to realize that there are four essential natural resources. Any place where these are found in abundance is inhabitable. These are protons, neutrons, electrons, and photons. Proxima Centauri itself is a source of photons. It almost certainly has stuff orbiting it - asteroids and comets that can provide protons, neutrons, and electrons.

Some day, an earth-based craft will arrive. It will enter orbit. It's occupants will go to work applying photons to protons, neutrons, and electrons, and a new community will be born. Given the slow rate at which red dwarfs consume fuel, the inhabitants of this system will see the Earth's sun grow red, burst into a planetary nebula, then shrink and fade from existence. However, they will have the potential to endure for tens to hundreds of billions of years, giving rise to other communities around other red-dwarf stars.

Except, that is far too far away for any reasonable predictions to be made. Just imaginings.

Tomorrow, I'll be coming back to earth.

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