In our last post, we pointed out that over-population is the worst problem
facing the world today. Well, at least a couple of ecologists in the Adirondacks
think it is. However, if we are scanning the horizon for things to worry about,
we mustn’t overlook collisions with asteroids. This week the Planetary
Defense Conference is holding a conference in Grenada, Spain. Although I
come to this as a layman, I must say that the prospect of the instantaneous
annihilation of the human race is a good deal scarier than the possibility of a
declining lifestyle in an increasing population.

Did you know that there are about 900 Potentially Hazardous Objects out there
-- asteroids and comets large enough to threaten Earth? This is an issue made
for population controllers in the United Nations. According to Dr Ray
Williamson, of the Secure World Foundation, "Because a NEO strike is an
international problem, mitigating NEOs will require international decision
making and international action, and this conference provides much of the
information needed to take action."

And the chances of rapid population decline are not negligible. If a white
paper at the 2004 conference can be trusted, we’ve got a big problem on our
hands:

"Impacts span a huge range in severity and frequency, and the means to
predict and mitigate these impacts vary accordingly. The probability of a
"dinosaur-killer" impact is about 1 in one million this century. The probability
of a civilization-ending impact is larger—a bit less than 1 in 1000 this
century. The probability of a small or Tunguska-class impact (near the lower
size for penetration of the atmosphere, but still large enough to destroy a
city) is higher still: There is approximately 1 chance in 10 of such an impact
this century."

From another point of view, perhaps it’s not something to worry about. If we
want to shrink the Earth’s population from 6 billion to 10 million overnight,
perhaps we should think of steering the planet into the flightpath of a
Potentially Hazardous Object.