Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Various existential risks have the potential to destroy, or drastically restrict, human civilization; could cause human extinction; or even cause the end of Earth. Severe events could cause the extinction of all life on the planet Earth, the destruction of the planet Earth, the annihilation of the solar system, to the annihilation of our galaxy or even the entire universe. Natural disasters, such as supervolcanoes and asteroids, may pose existential risks if sufficiently powerful, though man-made events could also threaten the survival of intelligent life on Earth, like catastrophic global warming, nuclear war, or bioterrorism. Learn more about other possible events that could cause a mass extinction, their likelihood and possible effects on our planet in this book.