Stephen Hawking has cancelled his scheduled appearance at the 2015 Glastonbury Festival.
The renowned physicist had been due to deliver a speech at the music event in Somerset on Friday (26 June), but pulled out at the eleventh hour for personal reasons.
Hawking suffers from ALS, a degenerative condition that eventually leads to the demise of motor neurons.
Reporting from Glastonbury, The Telegraph's Alice Vincent said earlier in the day: "I've just been up to the Kidz Field, where the friendly chaps on the door told me that Professor Stephen Hawking will not be there this afternoon – 'he's poorly', they tell me".
A spokesperson for 73-year-old scientist, whose life inspired the recent Oscar-winning film The Theory of Everything, later told the Telegraph has had to cancel for "personal reasons".
Although no further details were provided, BBC journalist Lizo Mzimba, tweeted that it was "unlikely" that the physicist will be rescheduling his Glastonbury speech for later in the festival.
Hawking had been set to speak to children about gravitational theory in the Kidz Field, the family-orientated section of the event.
His no-show comes just hours after rapper Azealia Banks also exited the line-up, axing her Saturday slot.