In 1908, a DD45-sized meteor exploded over Siberia with a force 1,000 times the Hiroshima blast. It leveled 80 million trees over an area twice the size of Los Angeles. If it had arrived five hours later, St. Petersburg would have been gone.
Scientists think there are millions of such "small" near-Earth meteors out there, and more than 1,000 that are at least a kilometer wide. Those are the ones that really leave a mark. Just ask the dinosaurs. And we're discovering more every day.
A few years ago, a book titled "The Black Swan" came out. No, it's not about swans singled out by the Cambridge Police Department for breaking into their own roosts, but about sudden, unpredictable events occurring far more often than we'd like to think. There are flocks of black swans out there, but we find it discomfiting to contemplate their existence.
In 2008, science writer Gregg Easterbrook surveyed preparedness for a "space-object strike" for the Atlantic magazine. He found that even though serious experts believe there's as much as a 1-in-10 chance of a significant Earth strike within the next century, NASA doesn't much care.
Things are improving, but it's still a cottage industry. A scientist quoted last month in Maclean's magazine noted that "there are more people working in a single McDonald's than there are trying to save civilization from an asteroid."
Meanwhile, the global warming industry -- and it is an industry now -- could fill football stadiums.
It makes you wonder. For all the rush and panic, the truth is, climate change -- if real -- is a very slow-moving catastrophe. Moreover, it happens to align with an ideological and political agenda the left has been pushing for generations: Unregulated economic growth is bad and must be controlled by experts; nature is our master, and we must be her servants. What a convenient truth for environmentalists.
Meanwhile, a "deep impact" is a terribly inconvenient threat, partly because it requires making peace with the idea that nature can be conquered.
Better to not even think about it.