Stephen Petranek counts down to Armageddon

Stephen Petranek counts down to Armageddon (video, 30 min). In this both serious and entertaining TED talk, the former editor-in-chief of Discover magazine discusses the 10 ways the world could end. I have been blissfully unaware of some of these scary scenarios before his talk. So if you have small children in front of your screens, better turn off the internet now, and keep it that way.
Petranek makes a rational argument for spending modest sums of money (around a few percent of some of the big ticket budget items) on preparing humanity to fight these pending disasters. Here are the top 5 of the 10 ways the world could end, with Petranek's proposed solutions. Interestingly, science and technology that currently exists enables us to address many of these problems. So despair not, my reader!


# 5. Reversal of the Earth's magnetic field. This happened in the past approximately every few hundred thousand years, and we may be overdue for such a reversal already. When this happens, for about 100 years the Earth's surface loses protection from cosmic rays and particles by a part of the atmosphere, including the ozone layer. Solution: learn how to artificially replenish  the protective parts of the atmosphere.
# 4. Giant solar flares. Astronomers who study stars of about the same age as our Sun noticed that many of them brighten by about a factor of 20, due to unusually strong flares (typical solar flares are now much weaker). Solution: start terraforming Mars (I love Petranek!). It is technically not impossible, but takes 300-500 years to produce a livable atmosphere there.

# 3. A new global epidemic. Solution: stop the practice of giving antibiotics to cattle and fish. This increases the frequency of antibiotic resistance genes in bacteria around us.
# 2. We meet a rogue black hole. There are ten million dead stars, now black holes, in the Milky Way alone. And a black hole only needs to get within a billion miles from Earth to affect us. This can cause Earth's orbit to become more elliptical than now, which will result in 150 degrees summers and minus 50 degrees winters. Solution: start colonizing space (don't you think Petranek is just great?). In any case, we have to get used to the fact that Earth will not last forever, the Sun will not last forever, and if humanity hopes to survive in the long run, we have to start exploring the Milky Way.

# 1. A really big asteroid heads for Earth. It is not a question of if, it is a question of when, and how big. In 1908 a small Tunguska asteroid flattened the woods for hundreds of miles. And in 1989 a large asteroid passed through Earth's orbit, through the place where we were only 6 hours before that. The result of an asteroid like this hitting the planet would be firestorms followed by nuclear winter-like global cooling from the debris it would kick up. The chances of a human dying from an asteroid are approximately the same as dying in an airplane crash. Yet we spend a lot more money preventing planes from crashing, compared to studying asteroids.
Solution: spend money and time monitoring asteroids and comets. There is currently no state sponsored monitoring of comets - all of it is done by amateur astronomers. NASA has successfully landed a small space craft on an asteroid already. We can use an ion propulsion motor to slowly change the asteroid's orbit so that it will not hit the Earth. As Stepehen Petrenk says in conclusion, the worst thing we can do is say, I got enough to worry about without worrying about an asteroid. That's a mistake that could literally cost us our future.

I am grateful to Stephen Petranek for providing a refreshing look at the really big picture, setting aside for a while "small" stuff like politics, financial crisis, wars, the stock market, and looking closely at us in the context of the Universe itself.