Stephen Hawking in 2007, experiencing zero-gravity. This plaque appeared on Pioneer spacecraft, in the hope of making extraterrestrial contact. After three years working on a new television series for the Discovery Channel , Stephen Hawking concludes that aliens are "almost certain to exist" and could even be dangerous. Hawking says that it is rational to assume that intelligent life exists somewhere in the universe , and mathematically unlikely that life is unique to the Earth , given the existence of a hundred billion galaxies, each of them containing hundreds of millions of stars. Hawking imagines nomadic aliens, having exhausted their home's resources, could attempt to take control of other planets, invading with "massive ships", and draws a comparison with Christopher Columbus discovering America, resulting in similar devastating consequences. With this in mind he advises "intelligent life might develop into something we wouldn't want to meet." However, he believes that the most likely forms of life would be microbes or simple animals on planets, in the centre of stars or drifting through space. The Drake equation , created in the 1960s, estimates the probability of extraterrestrial civilizations; feeding in modern research gives a high likelihood. The contradiction between this and actual discovery is known as the Fermi paradox . Sir Martin Rees , the Astronomer Royal, supports efforts to search for transmissions that might be artificial in origin. "Even if we couldn't make much sense of it, we'd have learnt that 'intelligence' wasn't unique to the hardware inside human skulls, and had emerged elsewhere," he said.
 in 2007, experiencing zero-gravity. This plaque appeared on spacecraft, in the hope of making extraterrestrial contact. After three years working on a new television series for the , Stephen Hawking concludes that are "almost certain to exist" and could even be dangerous. Hawking says that it is rational to assume that intelligent life exists somewhere in the , and mathematically unlikely that life is unique to the , given the existence of a hundred billion galaxies, each of them containing hundreds of millions of stars. Hawking imagines nomadic aliens, having exhausted their home's resources, could attempt to take control of other planets, invading with "massive ships", and draws a comparison with discovering America, resulting in similar devastating consequences. With this in mind he advises "intelligent life might develop into something we wouldn't want to meet." However, he believes that the most likely forms of life would be microbes or simple animals on planets, in the centre of stars or drifting through space. The , created in the 1960s, estimates the probability of extraterrestrial civilizations; feeding in modern research gives a high likelihood. The contradiction between this and actual discovery is known as the . Sir , the Astronomer Royal, supports efforts to search for transmissions that might be artificial in origin. "Even if we couldn't make much sense of it, we'd have learnt that 'intelligence' wasn't unique to the hardware inside human skulls, and had emerged elsewhere," he said.
D
Stephen Hawking
D
Pioneer
D
Discovery Channel
D
aliens
D
universe
D
Earth
D
Christopher Columbus
D
Drake equation
D
Fermi paradox
D
Martin Rees