Brown's team, using the Hubble telescope, found the object's diameter to be just 70km bigger than Pluto's.

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Dr Chatterjee therefore suggests that an object 40km in diameter hit the Earth off the coast of India and forced vast quantities of lava out of the Deccan Traps.

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Its smaller diameter is also good news, since there is still one chance in 1800 that the object could slam into earth in 2182.

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