Hawking celebrates 60th birthday despite broken hip
One of the world's most influential scientists has appeared at a conference to celebrate his 60th birthday.
Stephen Hawking, Professor of Mathematics at Cambridge University, broke his hip in a fall shortly after Christmas.
It is understood that Prof Hawking, who suffers from motor neurone disease, crashed into a wall after his wheelchair toppled on cobbles outside his Cambridge home.
A spokeswoman for the university said the professor is making a good recovery.
Prof Hawking's condition means that he cannot have a conventional anesthetic.
As a result he remained conscious during the surgery after being given an epidural.
