Professor Stephen Hawking, one of the most famous theoretical physicists in the world, just celebrated his 70th birthday, despite suffering from Lou Gehrig's disease that has rendered him wheel chair bound and dependent on computers to communicate.
In a radio interview marking his birthday, which covered a wide range of topics, Hawking repeated his oft stated assertion that humanity must colonize space in order to ensure its long term survival.
What sort of events could destroy the human race if it stays on one planet?
Hawking mentioned the possibility of nuclear war or climate change as being the cause of human extinction. A recent article in Discovery magazine also suggested that a global pandemic-possibly as the result of a bio-engineered disease-or an asteroid or comet strike could end the human race on Earth. The New Scientist chimed in with the possibility of a gamma ray burst caused by the explosion of a nearby star zapping the Earth with lethal radiation. Even events that do not wipe out the human species-say a total economic collapse-could end civilization and cause the deaths of billions as modern infrastructure breaks down.
How would space colonies ensure the survival of the human race?
The late Arthur C. Clarke often said, as recently as a 1999 interview in the New York Times, that it was dangerous for the human race to have all of its eggs in one basket, i.e. the Earth. The idea is that if human civilization were spread out to several worlds, starting with the moon and Mars, a calamity occurring at any one world would not result in the end of human civilization.
Are there efforts to colonize space ongoing?
Despite the fact that there is a lot of talk about exploring and eventually settling space beyond low Earth orbit, the answer is sadly no at this time. The Constellation program, which was envisioned to eventually lead to lunar colonies, was cancelled by President Barack Obama. That does not mean there are not ideas floating around to settle other worlds.
The moon is an obvious venue for the first human settlement. A Howstuffworks article describes how a lunar settlement might be set up. The moon has water, in the form of ice at the bottom of permanently shaded craters at the poles, oxygen chemically bonded with lunar soil, and a variety of other resources necessary for human survival.
Other visionaries point to Mars. Robert Zubrin, in his book "The Case for Mars," envisions the Red Planet as a second branch of human civilization. Eventually human settlers would use terraforming techniques to turn Mars into an analogue of Earth, with breathable air, running water, and an active biosphere where humans could walk around without need of space suits.
The late Dr. Gerard K. O'Neill suggested, in a book "The High Frontier," a more radical approach to colonizing space. Instead of going to another world, he envisioned humans-in effect-building their own worlds using extraterrestrial resources to build huge, rotating space colonies where people would live inside a rotating cylinder large enough to build small towns in. Such a colony was depicted in the science fiction TV series "Babylon Five."
Mark R. Whittington is the author of Children of Apollo and The Last Moonwalker . He has written on space subjects for a variety of periodicals, including The Houston Chronicle, The Washington Post, USA Today, the L.A. Times, and The Weekly Standard.