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Astronomers Unravel Marathon Mystery, Sounds Like Clearer Beer

by K. M. REESE
August 2, 2004 | A version of this story appeared in Volume 82, Issue 31



As the Olympic games in Athens approach, astronomers in Texas couldn't resist tinkering with the commonly accepted date of the first marathon run. Recall that the marathon had its genesis in 490 B.C., following a battle near the village of Marathon in Greece. The Persians had attempted an invasion, but they were sent packing by the Athenians. A messenger was dispatched from Marathon to run the roughly 23 miles to Athens to bring word of the victory and of possible further attack by sea. The runner, mission accomplished, promptly collapsed and died.

Historians have wondered why the presumably experienced long-distance messenger collapsed. Physics and astronomy professor Donald W. Olson and colleagues at Texas State University, San Marcos, say a possible reason was from heat stroke after running in extremely hot weather. The astronomers believe their idea makes sense because the battle apparently took place in August, not in September as previously believed.

In a report in the September issue of Sky & Telescope magazine, the astronomers point out that the accepted battle date of Sept. 12 is based on the timing of a known religious festival, which delayed the Spartans from marching to aid the Athenians. Both Athenian and Spartan calendars were lunisolar, following the phases of the moon but making adjustments to stay in step with the solar year. The problem was that the Spartans started counting with the first full moon after the fall equinox, while the Athenians started counting after the summer solstice.

Suffice it to say that historians calculated the date of the battle to be Sept. 12 based on the Athenian calendar, but the Spartan calendar should be used, the astronomers note. This switch puts the date of the battle on Aug. 12, because there were 10 new moons between the fall equinox and the summer solstice in 491-490 B.C., instead of the usual nine.

The temperature in the Athens region in August can reach 100 °F or higher--considerably warmer than in September, according to Olson and colleagues. Thus, they conclude that the first marathoner could have succumbed to the heat.

Sounds like clearer beer

The July 10 issue of New Scientist reports that Dutch filtration specialist Fluxxion is using a failed recording technology from the early 1990s to brighten and clarify beer. Fluxxion makes beer clearer by using a 15-cm-wide silicon wafer perforated with 0.45-mm holes to filter cloudy yeast residues out of the fresh brew. The company pokes the tiny holes into the silicon using a plasma beam--a method that Fluxxion's parent company, Royal Philips Electronics, developed in the early 1990s.

Back then, Philips used hot fluorocarbon plasma to punch 70-mm holes into metal film. The holey film could store data magnetically, and Philips developed the technology for its digital compact cassette (DCC) format. DCCs produced CD-quality sound, but DCC players were designed to also be compatible with analog cassettes. Forgetting the facile manner in which consumers tossed aside vinyl records and eight tracks, the electronics giant figured consumers would be eager to adopt a digital audio format that didn't make their music collections obsolete.

Of course, consumers were happy to abandon their cassettes for CDs, so DCCs never caught on. Nevertheless, Fluxxion's filters have caused quite a stir with brewers. Far less pressure is required to push brew through the Fluxxion filters because they are shorter and more regular than conventional beer filters, usually made from densely packed fibers or from diatomaceous earth called kieselguhr. The technology also appeals to brewers looking to phase out kieselguhr because of health hazards associated with handling and disposing of the dusty material.

Fluxxion tested the filters with freshly brewed beer from the Bavaria Brewery of Brabant. The brewery was so pleased with the results that it set up a pilot plant using the filters. Fluxxion is currently working on filters with even smaller pores in the hopes of removing viruses from blood plasma and bacteria from milk, thereby eliminating the need for pasteurization. Perhaps next they can think of something useful to do with abandoned Betamax videocassettes.

Ken is away. This week's items were contributed by Steve Ritter and Bethany Halford.


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