1. The religious view
Religion was the first to advertise about the end of the world. Both in Christianity and Islam we find many mentions of the end of the world. Apparently, in the final day, the death will be resurrected and God will judge all the persons who ever lived on Earth. This judgment day will be preceded by many signs and all humans will know that it is coming.
2. An asteroid impact
After the Judgment Day, this theory is the most popular regarding the end of the world. And with reason! A huge asteroid hitting the Earth – which happened many times in the history of our planet- would probably make the planet inhabitable for a long while. However NASA has some ways to stop the asteroid , such as blowing it up or trying to change its trajectory.
3. The death of the Sun
This is one of the greatest fears of the human kind. The death of our sun is a certain event because all stars have an “expiration date”. When this will happen, there is no chance that anything might survive, not even the smallest living organism. This is a really scary fact. But fortunately, our sun is young, so this is one event that we should not fear for another 5 million years.
4. An alien attack
Humans are really afraid of aliens, even though they never saw one still. An alien attack is not a real possibility, at least for now, since aliens were not even discovered yet. However, many people believe it to be a real threatening. The great number of movies illustrating this event might be an explanation for the paranoia that affects huge amounts of people.
5. A black hole
Nobody can deny that a black hole swallowing the Earth COULD happen, even though there is no actual threatening from this side. Firstly, we have a black hole in our very own Milky Way, right in the middle of the galaxy. This is not a thought that we may be comfortable with. Secondly, some people believe that the particle generator (Large Hadron Collider) we all heard of by now could generate a black hole but scientists deny the possibilty.
6. A supernova
The supernova is an exploding star that produces an immense amount of energy (the same amount as the energy produced by our sun in its entire life). The radiations of a supernova could really end life on Earth, by destroying the ozone layer. The supernova should be at a distance of maximum 26 light years from Earth so as to be lethal. This is a remote possibility, as it could only occur once in 670 million years.
7. A solar flare
A massive solar flare could collapse our power grids but, even most importantly, could kill us all, by destroying the ozone layer. There is no way of preventing such an explosion, or even knowing when is going to happen. The recent sun flares we all witnessed make experts fear that a more serious one could take place any time soon.
8. Gamma-ray bursts
They are the most powerful bursts in the Universe and they are also impossible to predict. Thus, there are enough are reasons to fear them, especially when thinking that they could cause the destruction of the ozone layer, as well as a global burning or darkening of the sky (by producing photochemical smog). So far, no gamma-ray burst took place in our galaxy.
9. Death of the Universe
No one knows if the Universe can die. But, since we all agree that it was once born, than logic tells us that it might die some day as well. Theories of how this could occur vary from scientist to scientist: some say that it will expand until all matter will become extremely thin, others believe that the Universe will fall back to a single point, from where a new Bing Bang will take place.
10. Reversal of the Magnetic field
Let’s be fair: this will only mean the end of the world as we know it. Humans and many other forms of lif might disappear too, but life on Earth will surely go on. This theory became popular with the release of the movie “2012”. The fact is that indeed, every once in a while, the Earth’s magnetic field reverses. Hence, the North Pole will become the South Pole and the other way around. This will cause many calamities, such as the destruction of the ozone layer and environmental disasters.
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