London: Renowned British scientist Stephen Hawking has missed a second celebration of his 70th birthday party because of ill-health.
The cosmologist was due to attend a reception last night at the Science Museum here in honour of his birthday and work.
Hawking, who was diagnosed with motor neurone disease at the age of 21, turned 70 on January eight. He was unable to attend a birthday symposium in Cambridge University on that day because of health problems.
Since Hawking was ill, his daughter, Lucy, represented her father at a new exhibition at the Science Museum entitled Stephen Hawking: A 70th birthday Celebration.
"It`s really sad that he can`t be here this evening. He would have loved to have been here with you all..," Lucy was quoted as saying by the Mirror.
Lucy Hawking, an author and journalist, accepted a special gift on behalf of her father from the science museum`s inventor in residence, Mark Champkins.
Entitled "black hole light", it was an illuminated model depicting spirals of light falling into a black hole.
Guests then raised their glasses to Prof Hawking in a "happy birthday" toast.
The new museum display includes a wide range of objects, papers and photos sourced from Prof Hawking`s own collection and previously unavailable to the public, the report said.
Among them is the blue suit he wore for a zero-gravity flight in 2007, a rarely seen 1978 portrait by David Hockney, and Prof Hawking`s annotated script for a 1999 guest appearance as a cartoon character on The Simpsons.
Prof Hawking recorded a personal message to be featured in the exhibition in which he credits the museum for "introducing young people to he wonder and excitement of scientific discovery".
"We have been very privileged to explore Prof Hawking`s archives, discovering early drafts of his hugely influential scientific papers alongside a rich array of popular material," Alison Boyle, curator of astronomy at the Science Museum, said.
"We hope that the selection we have chosen to display will offer a unique insight into the career of the world`s best-known scientist," Boyle said.