NATURE|Vol 453|22 May 2008 OPINION resent being defined by their trait. Medical is illusory — our DNA is popularly regarded geneticists have had to adapt to patients’ views as our medical fate, but DNA interrogations of themselves. more often yield notions of risk that have dif- To justify morally the genetic-screening ferent meanings to patients and physicians. programmes she writes about, Cowan cites Physicians rarely know the true cause of our the good intentions of the parties involved, complaints. In those genetic cases where sim- primarily their efforts to relieve suffering. plicity prevails, the testing technology is likely This criterion does not pass philosophical to be adopted. As law in the United States, the muster, nor is it sufficient to sway vehement Genetics Information Non-discrimination Act WWW.SUBTLETECHNOLOGIES.COM opponents. Although her analysis is cursory, may relieve some anxiety about the misuse of it does get to the heart of the matter: heredi- genetic information. If only it were so simple tary diseases cause great human suffering and to dispatch misery. everyone wants to help. Modern healers may claim science to be NORTHERN LIGHTS What no commentator on medical genetics the foundation of their work, but the key is, in The many shades of light in art and acknowledges is the hidden sadness, custom- fact, persuasion: to heed advice, to push and science are the focus of the annual arily buried, that each geneticist feels when persevere, to hope. As the genome is further Subtle Technologies Festival in discussing with patients and parents the dissected and better understood, no family of Toronto, Canada, starting this week. options for treatment, which are generally diseases warrants more genuine hope for suc- A symposium (from 30 May to 1 June) few and unsatisfactory. This takes its toll on cessful management than genetic conditions. will discuss the physics of light, everyone, although patients always astound Cowan understands that we must all share that its use in education, photography, with their resilience. hope for the campaign to be successful. ■ performance, new media and The hard truth is that genetics does not offer Hugh Young Rienhoff Jr is director of architecture. Sound artists muse easy answers. There are many genetic diseases, MyDaughtersDNA.org, based in San Francisco, about synaesthesia; a physicist and each one is unique. The simplicity of DNA California, USA. explains why painters love the light in Provence, France; and a biologist describes how to image cells. www.subtletechnologies.com A rough guide to Titan GREEN FINGERS Gardeners are the canaries of climate Titan Unveiled: Saturn’s Mysterious Moon state of our knowledge of this curious moon, change: first to notice buds blooming Explored and is accessible to most. Lorenz is closely early, lawns that need mowing more by Ralph Lorenz and Jacqueline Mitton involved with the Cassini mission to Sat- often and pests spreading in range Princeton University Press: 2008. 296 pp. urn and the Huygens probe it dropped onto as average temperatures creep up. $29.95, £17.95 Titan’s surface in 2005. The book focuses This week’s Chelsea Flower Show in on his key interests, which include Titan’s London (until 24 May), run by the Royal A future tourist guidebook to this remote surface and lower atmosphere, regions that Horticultural Society, includes scientific destination would warn us to bring our heavy- parallel Earth and are thus the most engag- exhibits to educate plant lovers about duty rain gear, but be prepared not to need ing for readers. climate change. UK researchers from it. Droughts may last many years there, but Titan Unveiled describes how most of the Tyndall Centre in Norwich, the when a hurricane-sized storm sweeps across what we once hypothesized about Titan has University of Reading, Rothamsted the sky, the rainfall is torrential. At high lati- been proved wrong. The story of how we Research in Harpenden, and others tudes, the landscape is dotted with thousands gained our current knowledge is fascinating; will be on hand to explain how plants, of lakes, some mere ponds and others inland even more intriguing is what remains to be ecosystems and practices must adapt. seas. Networks of channels and canyons are learned. Larger than Mercury, Titan is the www.rhs.org.uk/chelsea/2008 etched into the terrain, over which huge vol- only moon in our Solar System that is envel- canic domes loom. Other regions harbour oped in a thick atmosphere. Analogous to BEING HUMAN vast fields of dunes, some 100 metres high. Earth’s water-based weather system, Titan’s An exploration of what it means to be Welcome to Titan, Saturn’s largest moon. atmosphere experiences weather based human in a rapidly changing world and Our guidebook would go on to explain that on the phase changes of methane, shifting vast Universe is the theme of the 55th the dune particles are not sand, but hydrocar- between its gas, liquid and solid states. At Carnegie International. The largest US bons, totalling more than all the coal reserves the extremely cold temperatures on Titan’s survey of contemporary art, it opened on Earth. The magma flowing from the vol- surface (94 K, or –179 °C), water is frozen this month at Pittsburgh’s Carnegie canoes is not liquid rock, but a mix of ammo- and acts like rock. The moon is geologically Museum of Art (until January 2009). nia and water, similar to antifreeze. Liquid active, including volcanism and uplifting of Life on Mars, named after David ethane fills the lakes. And liquid methane mountain ranges. Deep under the icy sur- Bowie’s song, offers 300 works from carved the gullies at rates far in excess of the face, evidence for an ocean of liquid water 40 international artists, including Vija worst flash-flooding on Earth. and ammonia has been found. Celmins, who received the US$10,000 Titan Unveiled, by planetary scientist Ralph Scattered throughout the text are per- Carnegie Prize for her Night Sky series Lorenz and astronomy writer Jacqueline sonal anecdotes by Lorenz, labelled “Ralph’s of paintings. Mitton, presents a good overview of the Log”. Key to the book’s success, these sections www.cmoa.org CULTURE DISH CULTURE 453 OPINION NATURE|Vol 453|22 May 2008 convey how planetary exploration, Liquid ethane fills lakes it from Earth nearly every night, new and science in general, progresses as on the surface of Titan, discoveries are regular. It is inevitable a human enterprise. Lorenz commu- Saturn’s largest moon. that any book on Titan is a little out- nicates what it is like to be a scientist of-date before it is released, but this AP PHOTO/NASA AP PHOTO/NASA involved with a current space mission, reflects the vitality of the research. working with diverse colleagues and We won’t be able to book a ticket following your curiosity to make new to Titan in the next few decades, discoveries. but further robotic spacecraft will Advances may come serendipi- be sent to explore. A Titan orbiter tously, but they are usually hard-won could map the surface, observe the following years of intense work, car- seasonal weather patterns and study ried out with the risk of failure and the subsurface ocean. Balloon-borne research dead-ends. Some obstacles to detectors could examine the atmos- progress are simple to overcome. For phere and surface up close. And a example, Lorenz recounts how, while new mission will add detail to our working alone at night at an observa- guidebook to Titan. Hopefully, tory, he was once held back by a crucial piece Huygens probe after its launch. It required a someone working on that mission will write of equipment that lay behind a locked stor- major effort to retarget and replan nearly the an insider’s account, like Titan Unveiled, to age-room door. His eventual solution was to entire mission, involving hundreds of people tell us how it all happened. ■ remove the door’s hinges. Other challenges are and thousands of hours of work. Henry Roe is an astronomer at Lowell Observatory, greater, such as the discovery of an engineer- With the Cassini mission flying past Titan 1400 West Mars Hill Road, Flagstaff, ing problem with the radio transmitter on the every few weeks and astronomers observing Arizona 86001, USA. before the Second World War was Secrets How science hit the small screen of Nature (1922–33), produced by British Instructional Films. Its successor was Secrets of Films of Fact they stimulated demand for nature-based Life (1934–50). Celebrated cameraman Percy Science Museum, London films. Producer Charles Urban exploited Smith, a clerk at the UK government’s Depart- From 29 May to 2 November 2008. this commercial potential in a series of photo- ment of Education, worked on both series. He Films of Fact: A History of Science in micrography films called ‘The Unseen World: specialized in filming through microscopes Documentary Films and Television Revealing Nature’s Closest Secrets by Means of or glass aquaria in his London greenhouse, by Timothy Boon the Urban–Duncan Micro-Bioscope’, which using a timing device he made from a cuckoo Wallflower Press: 2008. 224 pp. included The Circulation of the Protoplasm of clock to record plant growth with time-lapse £45.00 (hbk), £16.99 (pbk) the Canadian Waterweed (1903). Nature series photography. quickly became established as a popular genre Television programming about science took “Is it not a scandal, in this day and age, that and remain so today, from movies of meerkat off in the mid-1950s in the United Kingdom, there seems to be no place for continuing series antics to marching penguins.