L. Kaltenegger: We can learn the future of Earth through the coming discoveries of small planets in the habitable zone.
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Michael Buble has been criticised as "disgusting" for posting a picture of a woman wearing tight shorts using the hashtag #beautifulbum.
Vinyl copies of a cover of Monty Python's 'Galaxy Song' recorded by Stephen Hawking go on sale later as part of Record Store Day.
The five-piece dance group do not sing but their choreographed back-flips had the crowd cheering at their audition in tonight's episode.