Asteroids : Assessing Catastrophic Risks

Sixty five million years ago an asteroid crashed into earth Global winds distributed the dust throughout the atmosphere, blocking sunlight, and many life-forms that relied on the sun eventually perished. In a short period of time, many experts believe, the mighty dinosaurs that dominated our planet went extinct. Realistically the same fate awaits us. Over 99.99% of the species that have ever existed are now extinct [13] [12]. If our species survives long enough, we will be exposed to an asteroid and could su§er the same fate as the dinosaurs. The data suggests that asteroids of that caliber will hit our planet on average once every 100 million years [12]. The last one was 65 million years ago. Under current conditions, when the next one hits the earth, humans and many other species could go extinct. What should we do about this threat to our survival and others like it? And if the issue is serious, why is this issue getting so little attention whereas the less catastrophic threat of global warming is in the news almost daily? The purpose of this article is to provide answers to these questions. We examine systematically how to deal with catastrophic risks such as asteroid impacts, which are small probability events with enormous consequences, events that could threaten the survival of our species, and compare their treatment with risks like global warming that are more imminent and familiar but possibly less catastrophic