Scientists with celebrity status may serve to popularise science, but is there a danger something is being lost in the process, asks Claire O'Connell

At first glance, footballer David Beckham and theoretical physicist Prof Stephen Hawking might not seem to have much in common. But look a little closer and you soon find they share the traits and shackles of a common phenomenon: celebrity.

Each one has vaulted outside his subspecialty of soccer or physics to reach a wider audience. Their well-publicised images are instantly recognisable. Their fame outstrips their renown. And salacious details of their private lives get splattered across the media at the hint of a scandal.

Hawking ranks among a coterie of "celebrity" scientists who can help popularise scientific ideas that might otherwise languish in academia, according to Declan Fahy, who is researching a PhD at Dublin City University on the phenomenon of the celebrity scientist.

"More and more these days, issues are seen through the prism of personality," he says. "One of the most important things for a political party is to have a good leader who can embody the party and underwrite the political values. The same thing is happening in science. Celebrity scientists are not just selling their books and promoting themselves - they are underwriting values about the scientific method and the claims that science has towards saying true things about the world."

Like many other celebrity scientists, Hawking crossed over into the public eye when he published a popular book, explains Fahy. "He was reasonably well known within physics when he was writing papers. But it was with A Brief History of Time that suddenly it all changed."

WRITING A CATCHY book or fronting a popular TV series about science often catalyses a scientist's shift from academia to a wider audience. But to qualify for real superstardom, other factors need to be in the mix, according to Fahy.

For example, a striking persona, appearance or style can become the scientist's individual signature, making them stand out from the crowd. And shrewdly marketed images of celebrity scientists have the power to persist: think of Albert Einstein's crazy hair or the wise aura of the balding and bearded Charles Darwin.

For Hawking, who has a type of motor neuron disease, his wheelchair-bound frailty adds a unique dimension to his public image. And, like the well-chiselled Beckham, Hawking's appearance is linked inextricably to his fame.

"Reviews of A Brief History of Time remarked on his illness and newspaper profiles refer to his appearance, his speech and his adaptation of work routines," notes Fahy. "Hawking is rightly acclaimed for having achieved so much despite his condition, but his fame is as much a function of his illness as his science, which is fairly impenetrable to the vast majority of people outside physics."

Having a rollercoaster personal life also helps boost media interest around the individual celebrity. Beckham is no stranger to gory details of his love life hitting the headlines. Similarly, Hawking also ratcheted up newspaper and magazine column inches when his first marriage broke up and he later wed his former nurse.

"It's a key feature of celebrity when their private life is being served up for public consumption. You don't really see that with ordinary scientists who are talking about a discovery, you don't know about their private lives," says Fahy.

In an age where Jade Goody and Paris Hilton can become celebrities, it may seem like a minor accomplishment to be in the public eye. But celebrity scientists tend to build their fame on a foundation of academic achievement, says Fahy.

"There's an idea about celebrity that it is a recent phenomenon that has only happened in the last 10 years. And the connotations are that stars are superficial and stardom is detached from real achievement. But science is different in that regard. You can't just be famous for being famous."

LIKE BECKHAM'S RIGHT foot, Hawking's intellect is not in doubt: he holds the prestigious Lucasian chair of mathematics at Cambridge University, an accolade once bestowed on Sir Isaac Newton.

However, even with a solid base, there is the danger of a celebrity's fame eclipsing their renown. Beckham is not considered as roundly talented as Zidane or Ronaldinho, yet he enjoys the most limelight. "Beckham's earning power and public recognition are viewed as being far greater than his football skills merit. He is viewed, at best, as a grafter blessed with an amazing ability to strike a dead ball," notes Fahy.

And while Hawking might place himself in a line with Galileo, Newton and Einstein, his peers don't seem to. A 1999 Physics World survey asked theoretical physicists to name the individuals who had made the most important contributions to the subject.

Hawking barely registered.

"In world historical terms he's maybe not as great as his public profile would suggest. But the promotions industry, his publishers, are very much putting it out there," says Fahy.

And while many scientists welcome public faces that can widen the appeal of their discipline, such intensive promotion of celebrity scientists can also breed professional envy among peers, the "tall poppy" syndrome.

The assumption lingers that someone who has time to write money-spinning books and appear on television can hardly be doing serious research. This is known as "The Sagan Effect" after the late US cosmologist, author and television star Carl Sagan.

"But for Sagan himself, the Sagan effect was a myth, it was grossly unfair," says Fahy, noting that despite the cosmologist's admirable academic output, he was denied tenure at Harvard.

CELEBRITY SCIENTISTS CAN also provoke criticism and ire for airing their personal views on matters outside their speciality, like religion; a controversial debate that has been known to make the letters page of this paper hum.

But overall, the presence of celebrity scientists serves a vital function in communicating science to a wider audience: "If you are presenting issues you need a human face and a human angle to communicate them effectively in public," says Fahy.

However, he notes that Ireland currently has no one who ticks all the superstar celebrity scientist boxes. And he doubts that our recent increased investment into basic science will automatically produce one.

"The formula for celebrity is very tricky - there are so many things that have to come together at the same time: their personality and the promotions industry along with actually achieving something and having the killer book or TV series.

"And efforts at manufacturing celebrity scientists have not been exactly stellar. As with other genres, like pop stars, you get very mixed results."

Meanwhile, Hawking's celebrity outshines Beckham's in at least one respect: the physicist has had the transatlantic cachet of being a character on The Simpsons.

Whether the footballer will match that upon his move to the US remains to be seen.