The X-ray was named the most important modern scientific achievement Wednesday in a poll conducted for Britain's Science Museum, beating Apollo spacecraft and DNA.
Nearly 50,000 members of the public voted in the museum or online on 10 of the greatest achievements in science, technology and engineering selected by the museum curators.
The X-ray machine topped the poll, which marks the London museum's centenary.
The discovery of penicillin antibiotics came second, followed by the DNA double helix.
After that, in order, came the Apollo 10 space capsule, the V2 rocket engine, Stephenson's Rocket steam locomotive, the Pilot ACE early computer, the steam engine, the Model T Ford motor car, and the electric telegraph.
The 10 are featured in a special section of the museum.
"I'm thrilled to see the incredible development of the X-ray machine recognised in the museum's centenary year," said Katie Maggs, the Science Museum's associate curator of medicine.
"X-rays have radically changed the way we see and understand our world -- our bodies in particular."
Britain's Culture Secretary Ben Bradshaw said: "Any competition that pits the Apollo 10 spacecraft against Stephenson's Rocket and the DNA double helix against the Model T Ford is bound to provide talking points a-plenty.
"The public's choice of the X-ray machine as the winner is testament to our insatiable curiosity to find out how things work."
(c) 2009 AFP
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