What button do you press to turn on tomorrow?

Science museums are now confronted by sophisticated visitors hankering after displays of nanofabrication, biotechnology and neutron beams. But how are curators more used to preserving the past going to present the technology of the future? Jon Turney reports

Newspapers and television are for news. Museums are for, well ... olds. And of all museums, science museums feel the tensions this evokes today most keenly. They were built, in the main, as monuments to past discovery and technology, as temples to progress. Now they are trying to establish new roles as contributors to public understanding of science. And they have to do this at a time when the inscrutability of technological artefacts and abstruseness of research is dispiriting for the casual inquirer, daunting even for the committed.

All this makes science museums some of the more interesting places to watch as they make their pitch for the millennium. Those running them have a hard job. Science museums face the same problems as other museums: visitors who demand something more compelling than cultural window-shopping or an improving hour for the kids; an intellectual culture obsessed with stories and symbols, in which staff have learnt that the narratives they build into exhibitions are always a selection from many alternatives; and increasing competition from other parts of the leisure industries, from theme parks to virtual reality "experiences".

On top of this, traditional science museums have some problems all their own. One is the advent of "science centres", usually built around hands-on exhibits. Inspired mainly by the Exploratorium in San Francisco and the Ontario Science Centre in Toronto, science centres are now a worldwide attraction. They often appeal to sponsors explicitly because they are not museums. They have no objects, no collections, no curators; no museum pieces. Just shiny new interactive exhibits.

A second problem is a stronger felt need to proselytise about science, but also to relate to changes in public attitudes to science and technology. Either way, it is clear old views of science as inevitably progressive meet a public increasingly sceptical about at least some aspects of science and technology - from animal experiments to genetic manipulation.

But perhaps the most difficult problem of all is the shock of the new. Visitor surveys show that what people want from their science museums is some effort to display contemporary science and technology, to acknowledge the world of black holes and biotechnology, neutron beams and nanofabrication. But how? Curators' expertise is normally bound up with the preservation and display of historic objects. Can they enlarge their job to capture something of the fast-moving frontier of present-day research?

Some answers emerged at a conference at the Science Museum in London last month, under the banner "Here and now: improving the presentation of contemporary science and technology in museums and science centres". But it also became apparent just how difficult a problem it is going to be.

The senior staff of the Science Museum were listening particularly closely, as they are spending Pounds 46 million from the Heritage Lottery Fund and the Wellcome Trust on a new wing, which will be devoted to contemporary science. What will be on offer there is not yet clear. Visitors to the Science Museum today can sample a slightly bemusing mix of galleries, some filled with the febrile bustle of exhibits designed to induce interaction at all costs, but most still dominated by the stillness of objects. And contemporary science there so far ranges from black holes or DNA fingerprinting in small temporary exhibitions, to the larger recent exhibition on Star Trek. This, they will tell you proudly, boosted visitor numbers by 80 per cent for the three months it ran. That is the kind of result museums would like from new exhibitions about real science. But can they get it?

There will certainly be plenty of people trying. Science centres, which have hitherto mainly confined themselves to fairly elementary stuff are also feeling the pull of contemporary science. The largest project in Britain looks destined to be the International Centre for Life in Newcastle, with Pounds million pledged from the Millennium Fund for a kind of genetics theme park. Other science centres would like to get away from 57 varieties of gadgets that invite what Joost Douma, director of the yet to open IMPULS Science and Technology centre in the Netherlands, calls "pinball behaviour".

Making exhibits that fit the bill demands a willingness to mount quite costly experiments, which sometimes fail. Charles Colson, director of life sciences at the Exploratorium, described efforts to involve visitors there in some real biology. His team spent nearly $100,000 developing a demonstration of cell destruction by the immune system. The effect, portrayed using a sheep blood cell to represent a "germ" and watching it disappear when attacked by the immune agent called Complement, is dramatic and repeatable. But making it work for visitors requires complex computer controls for a microscopic process, and further computer wizardry for a graphical interface for users. The result was an exhibit that "immunologists liked a lot" but few visitors followed through the sequence of events supposedly being demonstrated.

That project was put aside in the end not because it could not be fixed, but because enough had been spent on it for the time being. But those from more traditional museums, not surprisingly, emphasise that interactives must be mingled with object-based exhibitions "to engage visitors both with the dreams and the realities", as the Science Museum's Robert Bud put it. So the museum's display of a mummified "oncomouse" is both a representation of a scientific endeavour and a challenge to visitors' ideas about the legitimacy of manipulating life.

The oncomouse is getting pretty close to science-in-the-making. But what of truly contemporary science, where the research is not yet complete? Here, the Cambridge historian of science Simon Schaffer emphasised, one problem for the exhibition designer is that the facts are not yet established. As he put it, "authority and the facts are contemporaries of each other, one gets defined as the other does". The would-be exhibitor of contemporary science will usually have to buy in to one of several competing stories, but the version most scientists end up believing may not be the one originally chosen for display. In 1989, chemists praised the Smithsonian Museum in Washington for assembling material on cold fusion. A matter of months later, the museum was being criticised for giving space to the same objects, and allegedly lending credence to "bad science".

So is it better to leave the breaking news to the press, or to construct displays about the latest results that consist mostly of press-cuttings? The Science Museum's mini-display on life on Mars certainly consists mostly of newspaper facsimiles from this summer's press flurry about a Martian meteorite. No, don't leave these subjects, said Schaffer, but the museum's special contribution must be to show how the meaning of this particular lump of rock lies in long-unfolding stories, about meteorite samples and about the Red planet as a possible home for extraterrestrial life.

While it is undoubtedly eye-catching, the search for traces of life on Mars is far from the most contentious subject on offer. No one at the conference rose to the challenge posed by the Science Museum's Graham Farmelo, when he reported that none of 16 museums and science centres he canvassed (including his own) had done anything about BSE. The feeling seems to be that a subject that is getting saturation media coverage is either too familiar or too fast-moving to capture in a display. But this neglects the possibility that museums are places where the public might be involved in discussion about such issues.

Another challenge not immediately taken up was daunting for a different reason. Would anyone like a slightly used detector from the Large Electron Positron collider built at Europe's monster particle physics lab? asked a delegate from CERN. These multimillion-pound particle detectors are currently installed underground and weigh many tons, but the physicists will soon move on to an even larger project. They are not too large to be accommodated in South Kensington or in the great Deutsches Museum in Munich, for example. But what sense would visitors make of them out of context? It really takes a visit to CERN to grasp the scale of the enterprise, but it is a working laboratory, not a museum.

Particle physics, of course, is also an extreme case of one of the other hard problems of contemporary science for exhibition designers. Researchers now study phenomena so far from the everyday that they transcend the scales of visitor experience. Contemporary cosmologists think about a universe 15 billion light years across, while their colleagues in physics try to trace particles that may exist only for a minute fraction of a second. But museum discussion still turns on exhibition space measured in square metres, in which visitors may each spend a few minutes.

But despite all these problems, there are examples of success in mounting exhibitions about contemporary science. One such venture was the series of exhibitions mounted at the Canadian Centre Science North in Sudbury, Ontario. Here, a city of 160,000 is home to a science centre that attracts 200,000 visits a year and devotes a good deal of space to the unpromising-sounding subject of solar neutrino capture.

The reason this works is that Sudbury, a nickel-mining town, is also home to one of Canada's largest physics experiments, the Sudbury Neutrino Observatory. The inhabitants are naturally curious why scientists want to share their habit of going to work under 2,000 metres of rock, and the centre tries to tell them. It does not hurt, of course, that the observatory brings tax dollars and jobs to the town.

But even without getting much further into the physics than explaining that the neutrino is a highly "anti-social" particle, disinclined to interact, there is a lot that Science North can do to explain what goes on in the observatory.

One exhibit shows the working of the photomultiplier detectors used - possible because "they gave us all the defective units", according to the centre's programme director Munkith Al-Najjar. Another demonstrates the fantastic cleanliness required in the lab, and how this is achieved in old mine workings. A third shows the difference between heavy water, used in the detector tank, and normal "diet water".

Eventually, the centre will have live monitoring of neutrino events, perhaps 40 or 50 a day, and the exhibition will change as the observatory develops. The experiment, whose outcome is as yet unknown, appears to have gone quite a way to becoming the property of the local community. The challenge other curators and designers face is to achieve the same effect for museums and for visitors, who are inevitably much more distant from contemporary science in the making.

Jon Turney is lecturer in science communication, University College London.