By Drog, Section Ask SciScoop Posted on Fri Oct 03, 2003 at 07:36:54 AM PST
Last Wednesday, there was a story about how Earth's mass extinction 443 million years ago may have been the result of a massive gamma ray burst (GRB) from a collapsing star aimed directly at us. Today, a story in New Scientist said that an asteroid the size of a house recently flew past us at a distance of only 88,000 km--the closest approach ever recorded--with no warning at all. These stories got me to thinking (again) about how there are just soooooo many ways in which all (or most) life on Earth could be destroyed. A GRB destroys our ozone layer, blackens the skies and causes an ice age. An asteroid impact causes tidal waves, blackens the skies and causes an ice age. A nuclear war kills most of us, blackens the skies and causes an ice age. A genetically engineered virus kills us all. Self-replicating nanobots turn the world into grey goo. Global pollution destroys the ozone layer and causes a greenhouse effect that eventually makes Earth uninhabitable. We are unlucky enough to make first contact with an alien species that isn't very friendly. The list of potential final scenarios is very long. And quite depressing, if you allow yourself to dwell upon it.
But most of us don't, because we feel the danger isn't that great or because we think there's nothing we can do about it. And so, of course, we're not doing anything about it. Which is rather strange, because saving the human race from extinction is the sort of thing you'd expect most people to care about.
If we knew that a planet-killer asteroid would hit us in ten years, it's highly probable that we'd spend as much money as we could to develop a defence against it, because we would know that the expense is justified. But even though we could start building an effective asteroid defence right now, one that could detect them coming well in advance, and be able to destroy them or alter their course, the expense "might" be money wasted, or at least money spent before it was really necessary. We could also spend enormous amounts of money on trying to figure out a way in advance to replenish our ozone layer, or remove the nuclear fallout our atmosphere, or remove the atmospheric nitrogen oxides created by a GRB--"just in case".
But we probably won't. Because there are so many other things to spend money on--some of them very worthy, like feeding starving children, and some of them not so worthy, like developing advanced new military robots.
So what are our chances for survival? What will it take to spur us into action? A close call? The discovery of free energy (which would definitely impact our economy and ability to fund research)? Genetically enhancing the intelligence of our species? Is it even possible to defend ourselves against the above mentioned catastrophes or should we instead focus our efforts on seeding other planets with humans so that all our eggs aren't in one basket? Perhaps terraforming Venus or Mars, or sending seeding distant planets with humans via recombinant DNA sequencers ala Arthur C. Clarke's "The Songs of Distant Earth", or inventing anti-gravity engines or warp-drive engines to seed distant worlds ourselves?