Happy half century Hulk. It may seem incredible, he may be incredible, but everyone’s favourite not so jolly green giant has now been raging and rampaging across comic books and the small and big screen for a full five decades, most recently in The Avengers. Throughout that time we’ve also been battling to master what originally turned him from a mild mannered scientist into a super-powered monster: gamma radiation. And now there are signs of a significant breakthrough in our ability to manipulate it.
Dr Bruce Banner is transmuted by exposure to gamma rays in Hulk #1 in May 1962. In that first issue much is made of how no-one has previously unlocked “the secret of harnessing gamma rays”, and how “mysterious” and even “awesome” they are. Leaving aside some curious other elements of that debut – such as the Hulk being intended to be grey, but ending up green through colouring problems – what’s repeatedly emphasised is that gamma rays are “powerful forces” beyond our full comprehension or control. That was largely true then, and is still true now. Or at least it was until very recently.
The term gamma rays was coined in 1903 by Nobel-winning splitter of the atom Ernest Rutherford, as part of his ABC of radiation. He’d already come up with the names for alpha and beta rays when his work on radium led him to realise it was emitting something different: “rays which are non-deviable by a magnetic field, and which are of a very penetrating character”. So Rutherford gave them the next letter in the Greek alphabet, gamma.
Since then we’ve learned they are an intense, ionising form of electromagnetic radiation – therefore potentially bad news for anything living – which although distinct from X-rays in how they’re produced (gamma rays originate in the nucleus, X-rays outside it) overlap in terms of wavelengths and energies. We’ve even found some uses for its deadly properties – including sterilising medical equipment through irradiation and killing cancer cells.
Such details didn’t interest most makers of science fiction: what they picked up was that whereas X-rays had been subjugated and used in radiography and crystallography, gamma rays were mysterious and dangerous – a product of otherworldly cosmic rays or end-of-the-worldly nuclear explosions. The latter being something which at the height of the Cold War seemed all too likely. Gamma rays were the wild child of the electromagnetic spectrum – poorly understood, not easily disciplined and potentially life-threatening. All of which made them singularly attractive as a plot device.
Cold War classics include movies Monster on the Campus – gamma irradiated prehistoric remains lead to “evolution reversed!” for all who touch them - and The Gamma People where a crazed Eastern-bloc scientist turns up the rays by degrees (as in temperature!) to mutate locals. Comic book fans should note the first film’s lead character is Donald Blake – a name later given by Marvel to Thor’s human incarnation.
Fictional gamma radiation isn’t confined to the paranoia of the 50s and 60s or to being something bad. It has been evoked to generate dilithium crystals in a Star Trek movie (The Voyage Home if you must know), to catch and destroy a potentially dangerous robot in one of Isaac Asimov’s original I, Robot short stories, and as an experimental backdrop to the Pulitzer prize-winning dysfunctional family drama – later filmed with Paul Newman directing - The Effect of Gamma Rays on Man-in-the-Moon Marigolds. And they still get regular outings as something flexibly scary – an example being 2007’s Evolution of the Daleks where Dr Who’s old enemy need the energy from gamma rays to jumpstart another of their doomed schemes for galactic domination.
For over a century gamma rays have had a recurring cameo as the radiation from the wrong side of the tracks. The time, though, may have come to recast them in a leading role. We have finally discovered how they can be bent to our will. Not much, but enough to open up some interesting possibilities.
We’ve known since Newton’s work with prisms that visible light and many other kinds of electromagnetic radiation can be refracted and so focussed, but it was widely thought gamma rays were too intense and high frequency to be bent in any meaningful way. However, a team at the Institut Laue-Langevein (ILL) in Grenoble have just managed it. Speaking on Material World, Dr Michael Jentschel from ILL told me it had been so widely accepted it was impossible that “ nobody really looked into it much deeper”, but with improvements in gamma ray sources – like the powerful one at ILL – the time was right to try again. Having succeeded, Dr Jentschel believes it means there will be “a whole bunch of big applications coming in the next 10-20 years” including more sensitive and targeted medical imaging, new forms of treatment, and swift detection of nuclear weapons or other radioactive materials.
So as the Hulk turns 50, get ready for a gamma-ray burst of activity, and for this slice of the electromagnetic spectrum to be seen in a new, more positive light. As the Ramones almost put it in Pinhead, “Gamma, Gamma, we accept you, we accept you”.