Radiology Quiz

Usually, doctors post radiology quizzes with odd clinical findings, or
sometimes odd things that people have swallowed, or gotten into their
bodies through other means.

But this particular image has nothing to do with medicine, or even
traditional radiology.  Rather, it pertains to astronomy and
archeology.  

This is the famous href="http://en.wikipedia.org/wiki/Antikythera_Mechanism"
rel="tag">Antikythera mechanism, found in the
Mediterranean Sea, discovered in a shipwreck in 1901, off the coast of
the Greek island, rel="tag">Antikythera.  That's the origin
of the name of the mechanism, in case you were wondering.  It
is the world's oldest known analog computer.  



Recently, radiography has been used to figure out the inner workings,
and to confirm theories about the nature of the device.  It
was the subject of an article in Scientific American
in 1959, and is featured on the website, href="http://www.world-mysteries.com/sar_4.htm">World-mysteries.com.



Now, it is href="http://www.sciencenews.org/articles/20061202/fob6.asp">featured
in Science News, with updated information.  It has
been found to contain 30 hand-made metal gears.  

To make sense of that shattered structure, astronomer
Michael G. Edmunds of Cardiff University in Wales and his colleagues
have now applied two advanced imaging techniques to the shards. One is
X-ray computer tomography, which records views of an object like those
produced by a medical CT scanner. A high-power X-ray source penetrated
the dense relic with a beam narrow enough to reveal fine details, says
Andrew Ramsey, a tomography specialist with X-Tek Systems in Tring,
England.



"The computer tomography images of the mechanism have literally opened
the device up to us to see how it worked," comments ancient-astronomy
scholar John M. Steele of the University of Durham in England.



The researchers also applied a novel computer-enhanced, optical-imaging
technique for examining surface features.

Imagine someone putting that kind of effort, someday, into examining an
ancient Texas Instruments calculator.  



It has been confirmed that the Antikythera mechanism was used for
astronomical calculations.  



The top picture is from Wikipedia; the lower one is
too, but I first found it on href="http://antwrp.gsfc.nasa.gov/apod/ap061205.html">Astronomy
Picture of the Day.  As an aside, the
Wikipedia article, (linked above) now is in need of a "total rewrite,"
according to the editors.  Anyone who wants practice writing
about obscure topics, for free, is encouraged to contribute.