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SETI – why bother?


So, there are a lot of stars in the Universe.

And a lot of them have planets. Planets outside the Solar System are called exoplanets. Astronomers have looked for planets around a lot of relatively nearby stars. At least 1 in 20 of the stars has planets. Each of these stars could have several planets, and some of them could have planet-sized moons.

Nobody knows, but there could easily be about the same number of planets and large moons in the Universe as there are stars.

That’s a lot of places that COULD be something like the Earth.

Life has developed on Earth, and life is certainly amazing. Many people believe that something similar could have happened on other planets or moons.

Activity: Discuss:

Do you think that the start of life is something so unlikely that it could happen only once? Or can life arise wherever the conditions are ‘right’? What could those conditions be?


Next: Life in the Solar System


What's your opinion?

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Current rating: 4/5 (from 1 votes cast)

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NOT RATED holly 05-01-12 13:27
just been to mars, t'was gr8. met alienz one of dem waz called paul lol. i brought some sand back, sellin it on seek n sell on facey b, bidding starts at £10000000- anyone intrested? cyaaa xxxxxxxx
NOT RATED addy 05-01-12 13:29
i luv space! PEACE OUT!
Rebecca 20-12-12 11:55
Space LOL thats where Rivers Armstrong comes from xx
NOT RATED 18-06-15 14:30
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NOT RATED 16-07-15 12:33
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Aurora on Jupiter

Aurora on Jupiter
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Video Clip The Planet Hunters:

Find out how scientists are able to find planets orbiting other stars. Imagine trying to look through a telescope at an astronaut on the moon. Then think of looking at a penny that astronaut is holding up... edge on. What the astronomers are hunting is smaller than that.