As science has advanced, we’ve questioned almost everything around us - and as a result of that, we’ve realised that there was life before humans, and that life was wiped out by some very real catastrophes. But these catastrophes are still very real right now. What has happened to earth so far makes up only a fraction of what could happen. Here, I’ll look at possible apocalypse-inducing events that might take place, and tell you if you should be losing sleep over them.
Death by Asteroid
Well, first and foremost, the most publicized way the cosmos could destroy us - an asteroid impact. Things from space fall on earth everyday, but thankfully our atmosphere is thick enough to have most of them burn up due to friction. To cause considerable damage (destroy a city or two) an asteroid would have to be at least one kilometre across. On average, this happens after every 500 million or so odd years. We think that the dinosaurs were decimated by an asteroid 15 kilometres (6 miles) in diameter. Counting on the possibility that scientists would fail to notice something that big, we would be... dead.
The biggest volcano on the planet is Yellowstone. If it erupted, it would throw up 600 cubic kilometers of ash into the atmosphere. This would block out the sun for a long, long time, and perhaps introduce a new ice age. Yellowstone last erupted 70,000 years ago, and it is estimated that it erupts every 50,000 years. So in a sense, we are already overdue.
A solar flare of a high enough intensity would wipe out most of our satellites because of the overload of electrons that it causes. This would mean no internet, no GPS, no weather, and no surveillance. Most of the technology developed by mankind in the past 100 years would be wiped out. The sun’s solar activity peaks in cycles of 11 years. 2013 and 2014 are the peaks of the current cycle. If a coronal mass ejection is going to happen, its going to happen soon. What can we do to protect our technology? Michael Faraday invented an apparatus to protect objects from an excessive flow of negative ions - The Faraday Cage. The cage works because the outside electrical charge causes the electrical charges in the cage material to distribute so that the effect of the outside charge is canceled. Unfortunately, it’s not exactly practical to put giant cages around our satellites. All we can do is hope that a solar flare never happens (which it will, eventually.)
Cosmic Missile (Gamma Ray Burst)
When a star heavier that 50 solar masses (1 solar mass is the mass of our sun. Roughly 332946 times the mass of the Earth.) goes supernova, gravity causes most of its material and radiation to be ejected from its two weakest points - its south and north poles. When the energy from a star 16647300 the mass of the earth is concentrated into a single focused beam, nothing in that beam’s path is going to be pretty. A gamma ray burst can cause damage to the Earth only if its at least 8000 light years from the earth. Any more than that, we’re safe. Any less than that, we’re fried. Well, there isn’t a single star that could go supernova and wipe out the Earth with high-energy gamma rays. Right? Wrong. WR 104 is about 8000 light years away, just on the border of the safe zone. Wolf-rayent is a category of stars which are the only ones in the universe large enough, and bright enough, to fuse iron in their core. Normally, when a star’s core runs out of fuel its left with iron, which is almost impossible for a star under 200 solar masses to fuse. And when a star is able to fuse iron, you know that when it explodes - it won’t be a sight you’d want to see. Astronomers say that this star is in its red supergiant stage, meaning that it could explode very soon. As you can imagine, this isn’t exactly good news. Thankfully, we’re not hundred percent sure that this star is even pointing at us, and our ability to determine exact facts at distances of 8000 light years is still rather questionable. Likley or not, this would be a spectacular way to go.
Despite the fact that it may seem that the Earth could be annihilated any second, the odds are in our favour. Frankly, I’m more worried about slipping in the bathtub.