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the program. Hello about 400 years ago in Rome Giordano Bruno was burnt at the

stake for his belief in other inhabited worlds.

It's a possibility which is fascinated scientists, writers, artists and the general public for centuries

and any considerations of the origins of life and matter on other planets, and indeed this one,

inevitably raises huge questions.

Do other worlds exist?

How did our planet come into existence?

How can we know anything at all about the origins of life and

matter so many billions of years ago and how is our thinking on these among the

deepest of questions changed over the century. With me is the Astronomer Royal

Professor Sir Martin Reese who's also a Royal

Society research professor in Astronomer in Physics at Cambridge University. A leading research

on cosmic evolutions, black holes and galaxies, his books include black holes in the universe and

before the beginning our universe and others. He's particularly interested in

...