Last night a 900 foot wide asteroid made the latest in a series of close approaches towards Earth.
There is a chance it could collide with the Earth in 2036, the biggest threat would be if it fell on land mass.
Speaking to ITV Daybreak, Dr Maggie Aderin-Pocock said if it hits a city it would cause devastation.
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If Number 10 announces it plans to hold a vote on airstrikes in Syria, the planners in the MoD might as well get to work straight away.
Britain should not "sub-contract its security to other countries" while terrorists plan attacks from Syria, David Cameron will warn MPs.
The number of children dying from cancer in the UK each year is falling, according to new figures from a major charity.