08/01/2014 08:00 am ET | Updated Oct 01, 2014

Why We Need To Be Prepared To Leave Planet Earth

Growing up with science fiction's environmental nightmares, I did not imagine writing in a future of so many threats to human survival. Threats from our own wounding of nature and other natural threats which we have only recently understood. The fact that there were so many warnings in books set me into a naive assumption that disasters would not happen. I did not even consider how many thousands of people the planet kills every month, or how many we ourselves kill annually.

Many human civilizations have perished on our planet, little aware and even oblivious of what was happening to them. We were poised in the last century, and still are, to die by nuclear war -- and now face the ruination of nature's life support system through greed and denial. Human extinction is more than a mere possibility as we add to nature's threats of asteroid strikes, volcanic eruptions, earthquakes, pandemics, and its own climate changes. This is a large litany of bullets, many of which we can dodge, and others (like the Yellowstone volcanic caldera's long overdue capacity to destroy the northern hemisphere) we cannot do much about.

"Stephen Hawking's estimate of human survival has been steadily shrinking from the 1,000 years he started with to 100 or less."

Especially ironic today, for example, is the threat of fission power reactors. Two Japanese cities were destroyed by atomic bombs, and now the same technology invented by their American conquerors is threatening Japan and possibly all the Pacific waters. Robert Heinlein's 1940 story, "Blowups Happen," suggested that the only safe place for reactors might well be off the planet -- not because they could not in principle be made safe but because human errors are unpredictable. Our inner demons are beyond perfect control, and may block our way to mature technologies.

We are blinded by our short lives. We rebuild under Mount Vesuvius, in quake zones, flood plains, shorelines, and bet on being dead before anything can get us. We accept the fact that much of the planet's killings are beyond our control -- from the biological realm up to the geophysical. Deep down we seem to accept that humanity is an organism which can afford to lose individuals. Evolutionarily, some will survive, from bacteria and viruses to us. Killing and the acceptance of killing only makes organisms stronger. Bacteria and viruses know that evolution is a fact. We call our fight with them disease; with each other we call it war; the civilized call it murder. So much for the rise of individuality. Must we accept H. G. Wells's comment that "...neither do men live nor die in vain," which has become enshrined in our ways of war?

We have not gone far beyond all this; we do not count the cost of weapons, and we accept their use. Yet many of us now see alternative futures, and value the creative life of our world enough to want to do something about preserving it. What is our Earth worth to us? Is it worth everything, or do profit and loss statements decide that saving the world costs too much?

Stephen Hawking's estimate of human survival has been steadily shrinking from the 1,000 years he started with to 100 or less.

We have the knowledge to repair and save our world, and the means to develop what we do not yet have. Science fiction writer Larry Niven famously said that the dinosaurs died because they did not have a space program. Ours has been crippled for decades, with some high points (like the just launched Orbiting Carbon Observatory-2 satellite), but a greater program must develop solar system wide spacefaring, manned and unmanned, to open the resources of our sunspace to human betterment. Better than nothing to have had some spacefaring, but not having an effective space program, when you clearly can, amounts to suicide.

"Our eggs would no longer be in one very perishable basket."

The prophetic Russian physicist Konstantin Tsiolkovsky envisioned human habitats circling the sun. Our eggs would no longer be in one very perishable basket. Provision would exist for human survival against the worst happenstance; we have little of that provision now beyond luck. We need more baskets for our eggs.

What would our successor civilization look like? Space stations with full rotational gravity, bases on the moon, asteroids guided into safe orbits and mined, a Mars colony, the development of habitats inside the mined-out asteroids, a final victory of solar energy over Earth's damaging fossil fuels and the end of political power bought by coal, oil, and gas. "Earth is the cradle of civilization," wrote Sir Arthur C. Clarke, "but one cannot live in a cradle forever."

As a beginning writer, long before I wrote Macrolife and Cave of Stars, envisioning self-reproducing human habitats expanding beyond the Earth and its sunspace without ruining the chances for any upcoming planetary worlds in the imperial fashion of our own past, I had read a novel by anthropologist Chad Oliver, The Winds of Time, in which the survivors of an alien culture travel our galaxy in search of advanced civilizations which have not destroyed themselves. Their world is gone, destroyed by its own hand. Without spacefaring, it would have been a suicide.

It's a haunting story, later echoed by Carl Sagan in his original COSMOS series as perhaps not uncommon among developing worlds; but Chad Oliver's novel has a happy ending when the alien travelers find our Earth, not yet lost.

When the potential of the vast universe beyond our planetary childhood becomes obvious, we may feel as Thomas Wolfe wrote -- "Whoever needs the earth... shall dwell in one small room forever."

Will we have a successor civilization?

There is a way.