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Essay Contest: Physics in 2116


Nature surveys a century back, looks a century ahead in crystallography

It’s all because x rays “passing through a crystal bounce around to form an identifiable signature.”

UNESCO’s International Year of Crystallography has begun without much public attention. Among a few media stories, Time published a short piece on the centennial. Six countries from Australia to Belgium have issued postage stamps. The Royal Institution made a catchy three-minute video. Not much else has appeared, but maybe Nature’s 30 January special issue will stir some interest.

It’s not that scientists haven’t crafted pithy testimonial praise of x-ray crystallography, with its record of involvement in 28 Nobel Prizes. The Royal Institution video begins by reporting how Max Perutz—who shared one of those prizes in 1962—summed it up:

Why water boils at 100 degrees and methane at minus 161. Why blood is red and grass is green. Why diamond is hard and wax soft. Why glaciers flow and iron gets hard when you hammer it. The answers to all these problems have come from structural analysis.

In one of the Nature articles, “Crystallography needs a governing body,” Paolo G. Radaelli, professor of experimental philosophy and head of condensed-matter physics at Oxford, put it this way:

Aeroplanes fly safely because crystallography tests computer models of materials under stress. Drugs are more potent because crystallographers can see and modify how molecules interact with target sites in cells. An x-ray diffraction instrument on NASA’s Curiosity rover is now even studying the mineralogy of Mars.

A century ago, following Max Von Laue’s research, William and Lawrence Bragg—a father-and-son team—“fired a narrow beam of x rays at a humble salt crystal,” as the Royal Institution puts it, “and photographed the diffraction pattern as the crystals split the beam into many rays.” The pattern yielded information bearing on the atomic structure of the crystal.

What Nature today celebrates and elucidates, a Nobel Prize official, honoring the Braggs in 1915, foresaw:

Thanks to the methods that [they] have devised for investigating crystal structures, an entirely new world has been opened and has already in part been explored with marvelous exactitude. The significance of these methods, and of the results attained by their means, cannot as yet be gauged in its entirety, however imposing its dimensions already appear to be.

A century later, a celebratory Nature editorial, working in partnership with the special issue’s brief introductory article, extends that line of thinking:

[A]s this week’s special collection makes clear, crystallography remains a cutting-edge field, and one that, if harnessed properly, could contribute as much in the next 100 years as it did in the previous 100. The development of the x-ray free-electron laser, for example, is a monumental technical achievement, and one that seems more suited to the world of 2114 than 1914, or even 2014.

The special issue takes special note of crystallography’s relation to the issue of women in science. In a piece with a subhead about this “egalitarian, collaborative culture that has so far produced two female Nobel prizewinners,” Oxford science writer Georgina Ferry notes early on that a focus on a scientist’s gender rather than on her work can be “irksome.” She argues, though, that lessons for science in general can be discerned in crystallography’s features “that have attracted, retained and encouraged women.”

The special issue looks extensively at the science, technology, and technopolitics of the x-ray free-electron laser, or XFEL, which is pointed to in the “infographic” piece “Atomic secrets.” That heavily illustrated historical timeline uses brief annotations—for example, an entry citing Rosalind Franklin’s “photo 51,” the x-ray image of DNA that helped James Watson and Francis Crick model the double helix. It also offers snippet-length animations like “DNA in 3D.” Its entry for 1970 introduces synchrotrons as x-ray sources; for 2009, the XFEL.

XFELs “are at least a billion times brighter than synchrotrons,” declares M. Mitchell Waldrop, an editor with Nature in Washington, DC, in a three-page XFEL overview.  He quotes Keith Moffat, a University of Chicago crystallographer associated with the SLAC Linac Coherent Light Source (LCLS) at Stanford University: “XFELs, without any doubt, are disruptive technology, an advance that is so far beyond what has gone before that it alters the way you do things.”

Waldrop reports that experimental user demand for LCLS beam time is so high that the Energy Department is planning an LCLS-II, which he says “would triple the number of simultaneously operating experimental stations by 2018.” He summarizes the worldwide outlook:

The good news is that the LCLS-II and a flurry of other new machines will give researchers plenty of opportunities. Since 2011, for example, Japan has been operating its SACLA XFEL in Harima. Utilizing a specially built compact accelerator, SACLA is six times brighter and slightly higher in energy than the SLAC machine. In 2015, a consortium of European research institutions expects to finish construction of the €1.15-billion (US$1.6-billion) European XFEL in Hamburg, which will be just as bright as SACLA, and a little more energetic still.

With XFELs offering competition to synchrotrons, Sean McSweeney of Brookhaven National Laboratory and Petra Fromme of Arizona State University coauthored a Nature News and Views essay discussing the outlook for structural biology. And with crystallography’s scientific prospects burgeoning, Radaelli’s commentary engages the inevitable technopolitical dimensions.

Radaelli charges that “national and local interests are being put ahead of science.” He continues:

Crystallographers should take a lesson from particle physicists and create a body run by scientists for the governance of large international x-ray and neutron facilities. It should be guided by input from regular meetings of researchers from across the scientific community. This will ensure that the next generation of infrastructure will have the strongest possible scientific case, articulated clearly.

Concerning US potential, he adds this general criticism:

The effects of politics trumping science are being felt everywhere. In the United States, rivalry between national laboratories, state politics and a tendency by the Department of Energy to underfund instrumentation are widely believed to have hampered flagship facilities such as the Advanced Photon Source X-ray synchrotron in Argonne, Illinois, and the Spallation Neutron Source in Oak Ridge, Tennessee.

Whatever the future may hold technopolitically, the XFEL overview piece observes that eventually, “researchers hope to be able to get diffraction patterns from individual molecules, allowing them to watch biomolecules moving and interacting in a completely natural setting, surrounded by water, instead of trapped in the artificial environment of a crystal.” The article quotes Fromme: “That’s my future vision for crystallography. Get away from being a coroner imaging dead molecules, and instead get molecular movies.”




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