L. Kaltenegger: We can learn the future of Earth through the coming discoveries of small planets in the habitable zone.
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The group of Adelie penguins dwindled from 160,000 to 10,000 after an iceberg got stuck near their colony, scientists have found.
At least 10 people have been injured after more than 50 cars were involved in a pile-up on a busy highway in Pennsylvania.
A teenager who grew an incredible 10cm overnight after an operation to correct a curve in her spine has been given the all clear by doctors.