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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Late sunshine here and there this evening - but more cloud for southern Scotland, northern England and Northern Ireland again.
Pro-Leave campaigner Boris Johnson has responded in a politely worded letter to Jean-Claude Juncker's invitation to "come back to Brussels".
The Friends star had reportedly not seen her mother for several years following a feud - but reconnected with her shortly before she died.