Human Expansion into Space

Q. Will humans expand into space?

A. Yes. I am disappointed that the Apollo Project was not followed up with a start on colonization.

The Orion Project might have provided nuclear rockets that would have made colonization relatively inexpensive. Now NASA is thinking about nuclear powered ion rockets. These should make interplanetary journeys take a tenth as long as when chemical rockets are used.

Alas, NASA has taken over the name Orion for a chemical rocket system based on 1960s technology. Cute of them.

Q. Where should we colonize?

A. Interplanetary space, the moon and asteroids seem the most feasible.

Q. Isn't space essential for human survival for power satellites, material from space or relieving excess population?

A. No, it isn't necessary for any of these - at least for the next billion years. There are plenty of resources on earth for its expected future population. Space enthusiasts, who rely on arguments that space resources are necessary for mere human survival are doomed to disappointment for the forseeable future. There will continue to be good arguments that other solutions are cheaper.

The valid survival argument for space is to disperse human population, because of the possibility of a really bad asteroid strike or a really bad nuclear war.

Q. Should we do it anyway?

A. Yes.

Q. Why will people do it?

A. There are two possibilities. The first is that it will be done for the usual motivations of exploration, curiosity and adventure. The second reason why some groups of people will do it is to get away from the rest of us.

Q. What are the advantages of living in space?

A. There are a number of advantages.

Here's a fantasy about a human space based independent colony. They construct a model of the galaxy with all 10^(11) stars. If the model stars were a foot apart a cubical galaxy would be less than two miles on a side. Since the galaxy is not cubical, the space taken will be much more, say a light year per foot. The model is for children and others to play in. There's no gravity, so the children can fly themselves out on the spiral arms or into the core. A robot disreetly follows each visitor supplying food and removing wastes. A visitor can fall asleep whenever he wants to. Children brought up in space will find that easy, but visitors from earth may need something to cling to. [More to come.]

Q. What about interstellar travel and colonization?

A. With technology based on present science, multi-generation voyages will be required. Still, human society on earth can last for billions of years. Surely, the multi-generation voyages taking mere thousands of years will be undertaken in all that time. If human longevity is increased enough, 10,000 year journeys may be undertaken with the lifetime of the crew. Also if speeds close to the velocity of light can be achieved, the subjective time of the travellers for a journey will be less than that of the stay-at-homes in the ratio sqrt(1 - (v^2/c^2)). Poul Anderson wrote some nice science fiction novels about this. He took a rather gloomy view of humans maintaining their motivation for interstellar colonization.

Q. What about contact with other civilizations?

We should keep trying. However, the SETI (Search for extra-terrestrial intelligence) projects are relying on radio. It seems to me quite probable that civilizations whose technology is thousands or millions of years in advance of our own will use different means of communication than what can be invented a mere 100 years after the invention of radio. I admit I don't have any other definite technology to propose, although I'm working on a science fiction story in which beams of neutrinos are used.

When radio sources pulsating in the milliseconds were discovered, the LGM (little green men) theory was briefly entertained. Alas, they were just rapidly spinning neutron stars. I'm sure the LGM theory will be revived and considered if the astronomers discover any phenomena admitting that interpretation.

Up to: What futures shall we make?

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