UK Daily Mail 
Aug 9, 2010
Stephen Hawking has warned that unless the human race colonises space within the next two centuries it will disappear forever.
The famous astrophysicist says that our only chance for long-term survival is to move away from Earth and begin to inhabit new planets.
In an interview with website Big Think, Hawking said he was an ‘optimist’ but the next few hundred years had to be negotiated carefully if the human race is to survive.
He said: ‘I see great danger for the human race. There have been a number of times in the past when survival has been a question of touch and go. The Cuban missile crisis in 1963 is one of these.