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Is there life elsewhere in the Universe?

Using a robot device to discover alien lifeUsing a robot device to discover alien lifeExtraterrestrial life, or ET, is any life that does not originate from Earth. None has so far been discovered. Alien or extraterrestrial life includes anything from simple bacteria to intelligent, complex life-forms—perhaps even more advanced than us humans. The search for other worlds where life could exist covers our neighbouring planet Mars, more distant moons such as Enceladus, Europa or Titan, and planets in other solar systems many light years away.

Dishes used in searching for intelligent alien lifeDishes used in searching for intelligent alien life

Hot-water jets in the sea bed on EarthHot-water jets in the sea bed on Earth

Conditions for life

For living things to exist, there must be liquid water and a source of food. Some very simple life forms can live on chemicals in rocks. They can also survive in very hot or cold conditions. Some scientists think that life might be common in other worlds besides Earth. The discovery that warm-water oceans may exist beneath the crusts of moons like Enceladus and Europa has raised the possibility that alien life could even be found in own Solar System.

On 15th August 1977, a radio signal lasting 72 seconds was detected by a radio telescope used in the search for extraterrestrial intelligent life. A scientist wrote “Wow!” next to the signal on the computer printout, so that became its name. Despite repeated efforts to find out where the signal came from, it has not been detected since.

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