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“Supercomputers are awesome and why I love what I do!!!”

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This essay by Charles Day first appeared on page 88 of the January/February 2012 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society:

Tiananmen_275 My title comes from a comment made on Physics Today‘s Facebook page by Fernanda Foertter, a physicist who programs high-performance computers for a biotechnology company.

Although Foertter’s computational science background lies mostly in molecular dynamics simulations of polymers, her comment was about this post I wrote on colliding galaxies:

Here’s a great example of using computer simulation to help interpret observations. Jennifer Lotz of Space Telescope Science Institute and her colleagues modeled pairs of galaxies merging into each other. Stills from her movies were then compared with Hubble images of galaxies that looked as though they had just merged or were about to merge. The comparison yielded a new, more accurate estimate of the galaxy merger rate.

Until I encountered Foertter’s enthusiastic outburst, I hadn’t thought of supercomputers as being inspirational. As a science writer, I’ve seen plenty of stunning simulations of exploding supernovae, wiggling proteins, and other phenomena. I’ve written about climate calculations that gobbled up weeks of supercomputer time. Several Nobel Prizes, I know, have been awarded for work that required the services of high-performance computers.

But now I’ve come to realize that supercomputers are not just useful, they’re glamorous, too. What’s more, their awesome power could be used to encourage schoolchildren to think about careers in computational science.

To see what I mean, consider what is perhaps the most ambitious, most glamorous field of physics: particle physics. When I was in high school, I read Nigel Calder’s The Key to the Universe: A Report on the New Physics (Viking Press, 1977), which I found in my local library. There within its pages, in accessible prose accompanied by photos and diagrams, was the quest to discover the ultimate constituents of matter and the laws that govern their behavior.

Back in 1977, the world’s most powerful particle accelerator was Fermilab’s Main Ring, whose circumference and maximum collision energy were 6.4 km and 400 gigaelectronvolts. The current record holder, CERN’s Large Hadron Collider, is 27 km in circumference and is designed to reach 7 teraelectronvolts. When the LHC ended its latest science run in October, it had smashed together 7 × 1014 protons and antiprotons.

To me, supercomputing—or high-performance computing, if you prefer—is the particle physics of computational science. The world’s fastest computer, K, consumes 10 megawatts of electricity to carry out 8 × 1015 floating-point operations per second. The problems that K and other supercomputers are programmed to tackle are among the toughest and most important in all of science, such as understanding Earth’s changing climate and figuring out how 1011 interconnected neurons form a thinking human brain.

As I write this column, Supercomputing 2011 is being held at the Washington State Convention Center in Seattle. I was glad to see that the meeting’s education track has 19 talks altogether, including one entitled “Parallel: HPC Overview” by Charlie Peck and his colleagues.

Attending a lecture or class is still work to a student, no matter how interesting the topic. But reading a captivating book is play, and therefore more likely to fire a student’s imagination. I’ve just looked on Amazon for an inspiring book on supercomputing. I couldn’t find one.

The importance of clarity

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Two recent newspaper articles reminded me of the importance of clarity when writing about complex topics. In “Our feel-good war on breast cancer,” which was the cover article of last week’s New York Times magazine, Peggy Orenstein tackled the question of whether campaigns to raise awareness of breast cancer and urge women to have mammograms do more harm than good.

FeelGoodWar

Orenstein’s reporting of the question’s medical, social, and economic aspects is impressive, as are her fluid narrative and engaging style. She also succeeds in clearly conveying the tricky topic of how risk is assessed and described. Five-year survival rate, I learned, is a potentially misleading statistic.

But to me, what makes her article admirably distinctive is her account of her own experiences with breast cancer. Even though she benefited from the early detection of a tumor, she does not advocate universal early screening. Quite the opposite. Her final paragraph reads:

It has been four decades since the former first lady Betty Ford went public with her breast-cancer diagnosis, shattering the stigma of the disease. It has been three decades since the founding of Komen. Two decades since the introduction of the pink ribbon. Yet all that well-meaning awareness has ultimately made women less conscious of the facts: obscuring the limits of screening, conflating risk with disease, compromising our decisions about health care, celebrating “cancer survivors” who may have never required treating. And ultimately, it has come at the expense of those whose lives are most at risk.

The other reminder of clarity’s importance came in the form of an editorial in Tuesday’s Washington Post. Under the title, “EPA speaks on how much radiation is too much,” the newspaper’s editorial board opined on a proposal, released on 15 April by the US Environmental Protection Agency, to update the agency’s guide to emergency services in the event of a nuclear accident or attack.

The Post‘s editorial board duly weighed activists’ objections to the proposal, yet found in favor of the EPA—but with this sting in the tail:

The activists are right, though, about one thing: The document is a confusing bore. If the EPA wants city, county and state officials to pay attention—if it wants to make the case for practicality over the activists’ hyperbole—the agency ought to rewrite the guidelines in plain English.

My first encounter with the controversy surrounding radiation protection guidelines arose when I was assigned to edit Zbigniew Jaworowski’s article “Radiation risk and ethics,” which appeared in Physics Today‘s September 1999 issue. The article amounted to a long, multifaceted argument against the assumption that any radiation dose, no matter how small, could cause cancer.

The article was easy to edit. Jaworowski had organized the article deftly and made his points directly and with well-chosen evidence to support them. I was gratified to see that it spawned 12 letters to the editor, which were split between the April and May 2000 issues. Whether they agreed with Jaworowski or not, the letter writers had evidently understood his arguments.

Of course, scientists should strive to be clear even when they’re not engaged in controversy. And they should be especially clear when they propose a revolutionary new theory or experimental result.

One of my favorite examples of a clear, bold proposal is the paper that launched the field of chaos theory: Edward Lorenz’s “Deterministic nonperiodic flow,” which appeared in the March 1963 issue of the Journal of Atmospheric Sciences. Here’s a sample of Lorenz’s style from the paper’s introduction:

Lack of periodicity is very common in natural systems, and is one of the distinguishing features of turbulent flow. Because instantaneous turbulent flow patterns are so irregular, attention is often confined to the statistics of turbulence, which, in contrast to the details of turbulence, often behave in a regular well-organized manner. The short-range weather forecaster, however, is forced willy-nilly to predict the details of the large-scale turbulent eddies—the cyclones and anticyclones—which continually arrange themselves into new patterns. Thus there are occasions when more than the statistics of irregular flow are of very real concern.

Although you might get bogged down in the main, technical section of the paper, the entire introduction is accessible. And if that extract has whetted your appetite for more clarity about chaos, I recommend Adilson Motter and David Campbell’s May 2013 Physics Today article, “Chaos at fifty,” which celebrates the half century of research that Lorenz’s paper begat.

Monte Carlo, colloids, and public health

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C&Edec012_275 My first professional encounter with the Monte Carlo method came not during my long-abandoned career as an astronomer when I might have used the computational technique, but years later when I ran Physics Today‘s Search and Discovery department.

In 2004, I faced the task of describing a new Monte Carlo algorithm. Devised by Erik Luijten (while taking a shower, he told me), the new algorithm could do what the standard one, the Metropolis algorithm, couldn’t: efficiently simulate a colloid whose suspended particles had widely different sizes.

Suspecting that some of my readers might be unfamiliar with Metropolis, I included a short tutorial. I pointed out that using an alternative, more direct simulation method—molecular dynamics (MD)—was impractical: It’s possible to calculate the forces acting on all the colloid’s particles, but only for a modest number of consecutive time steps. The movie-like simulation that MD produces would be too brief to provide physical insight.

But the Metropolis algorithm, I told my readers, doesn’t follow every particle all the time. Rather, it calculates snapshots of the system and uses statistical mechanics to combine them. Comparing the two methods, I wrote:

So, if MD is like a movie, the Metropolis algorithm is like a sparse set of shuffled snapshots. If you simulated a cocktail party with the Metropolis algorithm, you wouldn’t see dynamical events, such as guests arriving and departing, or rare events, such as a waiter refilling a punchbowl. But, taken together, the Metropolis snapshots would fairly represent the party in full swing. From them, you could deduce whether, on average, people had enjoyed themselves.

My latest brush with Monte Carlo happened last week. Looking for research to write about, I came across a paper by Luis Zamora and his colleagues entitled “A Monte Carlo tool to study the mortality reduction due to breast screening programs.”

Screening for breast cancer is difficult and controversial. It’s difficult because the principal method, x-ray mammography, cannot by itself determine whether a lesion is malignant. Because of that limitation, follow-up biopsies are essential, but most lesions—roughly 4 in 5—turn out to be benign.

Controversy surrounds the question of when to start screening. Not only is the disease harder to detect in young women, it’s also less prevalent. Definitive evidence in favor of screening women aged between 40 and 49 years is lacking. Yet doctors—who treat individuals, not populations—are reluctant to tell patients under 49 that they don’t need a mammogram yet. Why take even a small risk?

The tool that Zamora and his colleagues have built simulates the fate of a population of women who enter a screening program. You can adjust the program’s age range and participation rate. Clinically derived parameters, such as the probability of detecting a tumor, are incorporated into the tool.

Zamora and his colleagues present their results in graphs and tables, which are hard to summarize in a short column. They predict, for example, that breast cancer mortality can be reduced by 29% if 100% of women aged 50–70 are screened every two years.

But they did discover what appears to be a critical parameter. For a screening program to be effective, its participation rate must be at least 50%. In the US, where 16.3% of the population lacks health insurance, that target is unfortunately ambitious.

This essay by Charles Day first appeared on page 88 of the March/April 2013 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.

Using statistics to catch cheats and criminals

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“If your experiment needs statistics, you ought to have done a better experiment,” Ernest Rutherford once declared. But when you work at the frontier of detection, as astronomers and particle physicists often do, you rely on statistical analysis to extract results. Indeed, if your experiment doesn’t need statistics, then you might be too far from the frontier to make an important discovery.

Despite such statistical triumphs as last year’s discovery of the Higgs boson, Rutherford’s disdain for—or at least suspicion of—statistics remains widespread. A recent statistical analysis demonstrated that visiting your doctor every year for a checkup doesn’t significantly prolong life. Of course, the practice doesn’t harm any individual patient, but its prevalence in the US raises the total cost of medical care, which harms society. Will the study make a difference? I doubt it.

Ernest Rutherford (1871–1937) and his coworkers discovered the atomic nucleus and the proton. They also performed the first experiments that transmuted one element into another. To learn more about Rutherford, visit the online exhibition Rutherford's Nuclear World. hosted by AIP's Center for the History of Physics.

Ernest Rutherford (1871–1937) and his coworkers discovered the atomic nucleus and the proton. They also performed the first experiments that transmuted one element into another. To learn more about Rutherford, visit the online exhibition Rutherford’s Nuclear World, which is hosted by AIP’s Center for the History of Physics. CREDIT: AIP Emilio Segrè Visual Archives (gift of Otto Hahn and Lawrence Badash)

I’m not sure what evidence would convince physicians to refrain from insisting on annual checkups, but they and anyone else who is skeptical of statistical analysis might be persuaded by a simmering scandal that boiled over recently in Atlanta, Georgia.

On 29 March the superintendent of the Atlanta school district, Beverly Hall, and 34 other educators were indicted in what a New York Times news story characterized as “the most widespread public school cheating scandal in memory.”

According to the indictment, the 35 educators conspired to raise students test scores by altering the tests after the students had taken them. Meeting in secret and wearing gloves to avoid leaving incriminating fingerprints, groups of teachers at various schools rubbed out wrong answers and replaced them with the correct ones.

Besides acclaim for appearing to fix badly performing schools, the conspirators also received cash bonuses. Hall’s totaled $500 000, according to the Times. One school, Parks Middle School, “improved” so much that it forfeited $750 000 in state and federal aid.

To gather evidence of a conspiracy that might convince a jury, Georgia state investigator, Richard Hyde, persuaded one of the teachers who was allegedly part of the scheme to wear a secret recording device. But evidence of a different kind had come to light five years earlier. In December 2008, the Atlanta Journal-Constitution drew attention to what seemed like suspiciously large and abrupt jumps in test scores. That initial investigation expanded into a five-year project in which three reporters and two database specialists gathered and analyzed test scores from 69 000 schools in 14 743 districts in 49 states.

The scores from Atlanta and few other districts stuck out as anomalous. As reported last June, some of those school districts are taking advantage of the Atlanta Journal-Constitution study to identify cheating educators.

Organized crime and electoral fraud

Similar statistical investigations can be found on the arXiv e-print server. Last month two physicists, Salvatore Catanese and Giacomo Fiumara and mathematician Emilio Ferrara, all from the University of Messina in Sicily, demonstrated that they could pick out organized criminal activity from cell phone records by looking for statistically anomalous behavior.

My favorite example—because it’s so similar to the Atlanta cheating scandal—was the study posted last year by Dmitry Kobak of the electrical and electronic engineering department of Imperial College London and two unaffiliated coauthors, Sergey Shpilkin and Maxim Pshenichnikov. Here’s the abstract:

Here we perform a statistical analysis of the official data from recent Russian parliamentary and presidential elections (held on December 4th, 2011 and March 4th, 2012, respectively). A number of anomalies are identified that persistently skew the results in favour of the pro-government party, United Russia (UR), and its leader Vladimir Putin. The main irregularities are: (i) remarkably high correlation between turnout and voting results; (ii) a large number of polling stations where the UR/Putin results are given by a round number of percent; (iii) constituencies showing improbably low or (iv) anomalously high dispersion of results across polling stations; (v) substantial difference between results at paper-based and electronic polling stations. These anomalies, albeit less prominent in the presidential elections, hardly conform to the assumptions of fair and free voting. The approaches proposed here can be readily extended to quantify fingerprints of electoral fraud in any other problematic elections.

As for Rutherford, I remain puzzled by his attitude toward statistics. The famous experiment that Hans Geiger and Ernest Marsden performed in 1909 at the University of Manchester under his direction revealed the existence of the atomic nucleus—after Geiger and Marsden had laboriously tallied the rare backward reflections of alpha particles from gold foil.

Does it matter that ScienceDaily republishes press releases?

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ScienceDaily is aptly named. The popular website has been posting copious news about science since its foundation 18 years ago. And I do mean “copious.” On 2 April, for instance, I counted 95 news items!

Given that ScienceDaily‘s staff page lists just two people, founder Dan Hogan and his wife Michele Hogan, the productivity seems remarkable—until you realize that all those stories, at least the ones I checked, are repackaged press releases from elsewhere.

As far as I can tell, the repackaging is minimal. Earlier this week, I posted a link on Physics Today‘s Facebook page to a Fraunhofer press release about a truck-mounted laser that can scan roads while the truck drives at highway speeds. The ScienceDaily version lacks the original’s figure, but the text is identical.

Further evidence of ScienceDaily‘s light editorial touch comes from a search for the British spellings “metre” and “litre.” As an American news outlet, ScienceDaily can be expected to swap the spellings for the American variants—if it did more than simply cut and paste the original British English press releases, that is.

ScienceDaily does not hide what it does. At the end of each story you’ll find a short description of the source, a note about editing, advice on citing the story, and a disclaimer. Here’s what’s appended to the piece about the truck-mounted laser scanner:

The above story is reprinted from materials provided by Fraunhofer-Gesellschaft.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Need to cite this story in your essay, paper, or report? Use one of the following formats:

  • APA
  • MLA Fraunhofer-Gesellschaft (2013, April 2). Surveying roads at 100 km/h. ScienceDaily. Retrieved April 3, 2013, from http://www.sciencedaily.com­ /releases/2013/04/130402091250.htm

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Whether ScienceDaily‘s behavior is unethical is not clear-cut. On the one hand, the website links to the original press release and to the institution that issued it. On the other hand, disclaiming the views in the article while recommending that ScienceDaily‘s version of the story be cited rather than the original comes across as a bid for the benefits of publication without the concomitant editorial responsibility.

But does it matter that ScienceDaily reproduces press releases? Could the practice even be good for the promotion of science?

Most, if not all, the science press releases I encounter are well-written and accurate. And although some of them sound overly enthusiastic, they tend not to exaggerate or misrepresent the implications of the research. Some press releases are better than the stories they prompt, perhaps because the people who write them spend more talking to researchers to get the science right than some reporters might.

There’s another reason to tolerate, if not welcome, what ScienceDaily and similar websites do. To quote the website’s advertising page,

ScienceDaily‘s Web site traffic averages about 45,000 daily visits, generating in excess of 150,000 page views a day, or a total of roughly 1.3 million visits / 4.5 million page views a month.

That’s a lot of people reading informative, professionally produced content about science.

Gaming in meatspace

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C&E275 One evening earlier this summer, I was enjoying a martini at a hotel bar in San Francisco’s SoMa district. Although I’d brought an engrossing book to read—Tokyo Year Zero by David Peace—I looked up now and then at the bar’s TV to watch the Miami Heat strive to nullify the Boston Celtics’ large early lead in game four of the NBA East finals.

During a commercial break, I became transfixed by a trailer for what seemed like an exciting new horror movie. Humans and zombies were fighting each other in a dark, empty New York and a bright, crowded Hong Kong. To catch the scenes of mayhem, the camera swooped, panned, and zoomed with unnatural agility and speed, greatly intensifying the thrills.

It turned out the camera work was unnatural. The trailer was not promoting a Hollywood movie, but an Xbox and PlayStation video game, Resident Evil 6. My long-held disdain for video games had been challenged!

The first video game I encountered was Space Invaders, which appeared in one of my hometown pubs around 1980. In case you’ve forgotten or never knew, the game’s object is to shoot down an armada of alien spacecraft, each depicted within a 16- by 16-pixel grid. But crude graphics weren’t what put me off Space Invaders and its descendants. Rather, I couldn’t see the point of acquiring the skill needed to win: the ability to press the controller’s buttons quickly and accurately. I still don’t—even to play Resident Evil 6 on a 1920- by 1080-pixel monitor.

Besides making me reconsider video games, my chance encounter with computer-animated zombies made me wonder why I’ve recently come to enjoy playing board games, despite the gulf between the games’ typically rich scenarios and their manifestly artificial boards. In Railways of England and Wales, for example, players vie to build the most profitable rail network between a limited number of major towns and cities, just as their historical counterparts did in the early years of Queen Victoria’s reign.

The state of play during a game of Railways of England and Wales. The image comes from BoardGameGeek, where you can find a description and review of the game.

The state of play during a game of Railways of England and Wales. The image comes from BoardGameGeek, where you can find a description and review of the game.

Although the board and accoutrements of Railways of England and Wales are somewhat cartoonish, I and my fellow players Jan, Kate, Kevin, Stacy, and Ty borrowed money, laid down track, bought rolling stock, and transported goods with gusto. The locally brewed beer and home-pulled pork served by our hosts, Stacy and Ty, added to the enjoyment.

So why do I prefer playing at railway barony on a cartoonish board to shooting zombies on a realistically rendered street? Paradoxically, when it comes to human behavior, Railways of England and Wales seems more realistic than Resident Evil 6. Whereas real railway barons schemed while sitting in chairs and looking at maps, “real” zombie hunters should be running outside and shooting weapons. The first activity resembles its corresponding game; the second doesn’t.

But even if I don’t succumb to the attraction of playing video games, I’m affected by their popularity. You are, too. In an article published last year, Martin Hilbert and Priscila López determined that video games consumed 42% of the world’s capacity to store information in 2007, up from 5% in 2000. Video games’ share of total CPUs grew at a similar rate, from 5% in 2000 to 25% in 2007. Your next home computer could be optimized for Resident Evil 6, whether you play the game or not.

This essay by Charles Day first appeared on page 88 of the September/October 2012 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.

Mind-reading computers

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EchoCharles275 Last year, the website of Britain’s Daily Mail newspaper became the world’s most-visited English-language news source. Although the Mail‘s website owes its popularity to a menu rich in celebrities, crime, and royals, it offers readers something that my stuffier hometown newspaper, the Washington Post, lacks: a top-level section devoted to science.

Granted, the Mail’s science coverage tends toward the sensational, but it does encompass superluminal neutrinos, the Higgs boson, and other weighty topics. The story that led the science section on 1 February 2012 was both sensational and important, as you can tell from the headline:

Mind-boggling! Science creates computer that can decode your thoughts and put them into words.

The story’s origin lies in an article published in PLoS Biology by Brian Pasley of the University of California, Berkeley, and his collaborators. Fifteen patients who suffered either epilepsy or brain cancer agreed to let Pasley’s team attach an array of electrodes to their brains while their skulls were opened for surgery. The electrodes recorded signals from neurons located in a part of the brain, the auditory cortex, that interprets spoken language.

Before the patients underwent surgery, they listened to single words and whole sentences. Pasley and his collaborators correlated the electrical recordings with the words’ acoustic spectra. A machine-learning algorithm then derived a mapping that could reproduce an acoustic spectrum from a neural recording.

Predicting what someone hears based on his or her brain activity is impressive, but it hardly qualifies as mind reading. However, it turns out that the auditory cortex is also responsible for encoding speech. When Pasley’s team asked each patient to think of words without uttering them, the algorithm accurately predicted what those unspoken words were. In that sense, the algorithm really did read the patients’ minds.

Pasley’s algorithm occupies one front in a broad campaign to understand how the human brain works. On another front, biophysicists are developing ways to map the topography of the brain’s interconnected neurons. Given that the human brain contains on the order of 1011 neurons, each of which is connected to up to 1000 other neurons, assembling a complete neuronal map could turn out to be infeasible—and perhaps unnecessary.

A detailed map of a single, characteristic neighborhood of the brain might yield enough information to identify the physical features that underlie thought and memory. But knowledge of those features alone might fall short of demonstrating that someone understands the brain. If that turns out to be the case, then a convincing demonstration might entail building a simulated brain.

The anatomy and physiology of such a brain wouldn’t necessarily resemble those of our own. Indeed, the first prototype could turn out to consist of a building-sized stack of optical tables where pulsed beams of light—the information-carrying signals—bounce off mirrors and pass through prisms. Provided that the simulated brain’s topology and interconnections are described using the same mathematical equations that apply to a human brain, such a demonstration would be valid.

And if that fantasy becomes a reality, simulation would have attained a new and higher status in science. Rather than providing a way to calculate a theory’s validation, the simulation would be the validation.

This essay by Charles Day first appeared on page 104 of the July/August 2012 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.

Standards rule OK

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My title comes from the chorus of a song on the Jam’s second album, This Is the Modern World (1977). Written by the band’s singer and guitarist Paul Weller, the song is a bombastically ironic attack on the enforcers of social conformity.

But if Weller were not a socially conscious rock musician and instead were a computational scientist, he might have still chanted, “Standards rule OK!” For without standards in hardware, software, and data formats, our work would be less efficient and less effective.

I first appreciated the importance of computer standards when I worked at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in the early 1990s. My field, x-ray astronomy, was just three decades old at the time. The first pioneering missions could detect only a handful of bright objects. But their successors—among them the European Space Agency’s European X-ray Observatory Satellite (EXOSAT; 1983–86) and NASA’s Einstein Observatory (1978−82)—observed thousands of x-ray emitting stars, galaxies, and other cosmic objects. Then came Germany’s Röntgen Satellite (ROSAT; 1990−99) and Japan’s Ginga (1987−91), which added to that swelling collection.

Because spacecraft telemetry is limited by bandwidth, the data gathered and beamed to Earth by satellite observatories are packaged in efficient, instrument-specific formats—15 altogether for the instruments carried by the four spacecraft listed above. In contrast with the diversity of telemetry formats, the figures that embody the data’s scientific content (and ultimately appear in research papers) typically come in a smaller set of generic flavors: images, spectra, and light curves.

Creating those figures entails background subtraction, binning, filtering, and other generic tasks. In principle, the software that, say, Fourier-transforms a data stream from EXOSAT‘s Medium Energy instrument could do the same for a data stream from Ginga‘s Large-Area Counter. But the raw formats are as different as Dutch and Japanese. If the same software is to work with data from those and other missions, the data must be translated into a common format. And that format must be flexible enough to accommodate new instruments.

My former colleagues at GSFC duly picked such a format: flexible image transport system (FITS). Originally developed for optical and radio data, FITS makes extensive use of headers and keywords. Like XML, FITS is extensible. Whenever a new detector technology comes online, new keywords and data structures are defined within the FITS framework. Granted, someone has to write an instrument-specific program that translates telemetry into FITS, but no one has to take on the more onerous job of rewriting data analysis software.

When I left GSFC in 1997, astronomers there and elsewhere used three software programs to analyze their data: Xspec (for spectra), Xronos (for light curves), and Ximage (for images). Now, 14 years later, they’re still using the same three programs for data from observatories that launched years after my departure.

FITS made its public debut in 1981 in a paper in Astronomy and Astrophysics. On 30 November of that same year, the Swedish pop group ABBA’s eighth and final album The Visitors became the first recording available on a new format, the compact disc. Although CD sales are waning, it remains a durable standard—at least I hope so. I have six Jam CDs.

This essay by Charles Day first appeared on page 96 of the September/October 2011 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.

Earthquakes, soft bombs, and internet vulnerability

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Once I’d taken in the devastation wrought by the Tohoku earthquake and tsunami, my thoughts went to the physicists I knew at Tohoku University. The university is located in the city of Sendai, 81 miles from the earthquake’s epicenter and just 10 miles from where the tsunami hit land.

News was frustratingly difficult to obtain at first. Tohoku University’s website was down; emails were either not get­ting through or not being answered. On 16 March, five days after the earthquake struck, a friend of mine posted on Physics Today’s Facebook page that he’d heard from an old classmate of his, a nuclear physicist at Tohoku Univer­sity. Some campus buildings were damaged, but there were no casualties.

I learned later that the earthquake had damaged power lines and telecommunications cables. What’s more, the shutdown of Fukushima I and other nuclear power sta­tions in northeastern Japan had created a power shortage. Even if telecommunications cables or cellphone towers had remained operational, information would have stopped flowing on the internet due to a lack of electro­motive power.

That information is intrinsically physical and requires energy to store, process, and transmit is a familiar con­cept to physicists. But I was still surprised that an earth­quake had shut down, or at least slowed down, Sendai’s internet. After all, the internet’s message protocols and network structures were designed to survive nuclear attacks.

Given the nature of warfare, you can presume that if one group of military thinkers has devised a new weapon, another group will try to devise a countermeasure. I don’t know whether the US Pentagon’s ­BLU-114/B “soft bomb” was designed to take out an enemy’s internet, but, by targeting power plants, it could achieve that goal, too.

The soft bomb is a remarkable weapon. Within the bomb’s casing are a classified number of bomblets that contain a classified number of chemically treated graphite filaments. When detonated over a power plant, the bomb­lets release the filaments, which spread and fall in a dense cloud. Because graphite is a conductor, the filaments short­-circuit transformers on contact, leading to damaging lightning­-like discharges.

During the 1999 Kosovo War, the US Air Force’s F­-117 stealth fighters dropped soft bombs to temporarily disrupt or knock out 70% of Serbia’s electricity­-generating capacity. According to a timeline of the war published by Rasmus Ole Rasmussen, Bent C. Jørgensen, and Bernhelm Booss-Bavnbek, Belgrade’s power was cut off on day 66 of the war. Six days later, on 6 June, Slobodan Milošević accepted NATO’s peace plan.

I hope military thinkers are devising ways to protect the internet’s physical infrastructure—if not from soft bombs, then at least from earthquakes and tsunamis.

This essay by Charles Day first appeared on page 104 of the July/August 2011 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.

The Elements: An Illustrated History of the Periodic Table

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Even though my interest in science developed in my early teens, and even though my love of reading developed earlier, I didn’t read many books about science in my childhood. In fact, only two science books stand out in my memory: Nigel Calder’s The Key to the Universe: A Report on the New Physics (Penguin, 1978) and Jane Werner Watson and Rudolph F. Zallinger’s Dinosaurs and Other Prehistoric Reptiles (Paul Hamlyn, 1960).

Calder’s book, which I read soon after it came out, influenced my decision to study physics at university. Watson and Zallinger’s book made an earlier and different impression. The 10-year-old me was enthralled by Zallinger’s vivid and lively illustrations, such as the one above. Not only were the dinosaurs and other creatures depicted as they might have been, but so too were the plants and landscapes.

Those memorable books came to mind when I read—or, rather, dipped into—a book that Tess Woods of Newman Communications had sent me to review, Tom Jackson’s The Elements: An Illustrated History of the Periodic Table (Shelter Harbor Press, 2012). The book is one of three in the Ponderables series. The others, also written by Jackson, are about mathematics and astronomy.

The bulk of Elements consists of 100 short, chronologically arranged chapters. The first, “Stone Age Chemistry,” discusses fire, food, and cave paintings. The last covers the recently discovered Higgs boson. In between, Jackson tells the story of humankind’s gradually growing awareness of chemical science and its applications.

It’s a measure of Jackson’s skill that I couldn’t tell at what age group his book is aimed. Inquisitive high schoolers and adults alike will enjoy and learn from what’s inside. Despite my professional interest in science, I discovered something new from almost every chapter. Did you know that the first plastic polymer, Parkesine, was invented in 1856 by Alexander Parkes and that it found use, decades later, as celluloid film stock? Or that the Periodic Table’s resemblance to an upside-down game of Solitaire is not a coincidence? I didn’t.

But Elements is more than a collection of interesting facts. Much of chemistry is ultimately about the arrangement and rearrangement of electrons. As if to emphasize that point, Jackson weaves the history of electromagnetism into his story. Readers learn about the first batteries, electrolysis, Coulomb’s law, J. J. Thomson’s discovery of the electron, and other electromagnetic milestones. Radioactivity and quantum mechanics are also covered.

The book is also more than a history of past discoveries. Its penultimate section, “Imponderables,” outlines seven open questions in chemistry, including these three: Why is nature one-sided? Is bismuth radioactive? Does francium exist? The book’s effect on young readers, I hope, will be to inspire some of them to meet the continuing challenge of understanding the universe and its contents.

The book’s effect on older readers, I expect, will be to impress on them the sheer scale of scientific progress. No other human endeavor—not art, not literature, not politics, not even exploration—can match the immensity of science’s upward leap from making fire to discovering the Higgs.