A group of scientists from the University of California-San Francisco is worried that a new generation of airport security scanners could present a cancer risk, NPR reports. But skeptics say people flying at 30,000 feet are already bombarded by cosmic rays, so a brief trip through an X-ray machine on the way to the plane is a drop in the radiation bucket.
After the "underwear bomber" incident on Christmas, the Obama administration ramped up deployment of advanced scanners that can spot explosives or weapons, NPR says. Some 1,000 new machines will be in use by the end of next year, roughly half of which are X-ray back-scatter scanners. The machines, which can look beneath passengers' clothes, expose passengers to ionizing radiation for about six seconds.
Like many pieces of modern medical equipment, X-ray machines are as bulky and energy dependent as they are vital. Even "portable" X-ray machines remain too heavy to carry across rough terrain, and too energy hungry to run off batteries. That's why Radius Health's portable, low energy X-ray machine may revolutionize medicine in disaster zones, on the front lines, and at patients homes.
If Superman saw in terahertz radiation, he could do more than just peer through clothes and the human body. The Man of Steel might also be able to identify the chemical difference between a benign powder or an explosive tucked away inside a vial within a suitcase -- assuming that he could somehow tune his vision.
No worries, because an MIT electrical engineer and colleagues have managed to tune a small but powerful laser capable of generating terahertz rays. That could someday lead to airport scanners capable of even better snooping than superheroes.