That’s the vision of a number of researchers at Purdue University, West Lafayette, Ind., who are working along with the state of Indiana to develop an advanced sensor system that will use the millions of ordinary cell phones to automatically detect and track nuclear and radiological weapons, which they believe pose a clear and imminent danger to the American homeland.
“The president of the United States, George Bush, has stated repeatedly that a smuggled nuclear weapon is the number one physical threat to the USA,” Andrew Longman, a consulting instrumentation scientist who developed the software for the system, told HSToday. “There is little way for a terrorist to hit the United States, or civilization, in any way that will permanently or deeply affect it other than via nuclear weapons. With 10 smuggled nuclear warheads, terrorists could kill 10 million people and leave another 300 million under threat of blackmail. One bomb the size of the Hiroshima bomb, detonated in Manhattan, could kill 50, a hundred, or 200,000 people. It is a matter of time and technology until the terrorists have these kinds of weapons.”
Defeating the dirty bomb
Presently, there is no way to detect or track the presence of a “dirty bomb” or any nuclear material in a city or any densely populated area. A terrorist could easily load a bomb capable of killing a million people in the back of a car, drive to a desired location and detonate it without setting off a single alarm or being detected in the slightest way. Given the immensity and urgency of the threat, experts believe that it is vitally important to develop effective radiological detection networks as soon as possible.
“There is documented intelligence and evidence of the intent to acquire and use nuclear devices against civilian populations,” explained Stephen Buerle, director, Enterprise Security, Unisys, Blue Bell, Pa. “We must remember that a fairly mature black market for nuclear material, devices and associated intelligence exists—dating back at least to the early to mid-1980s. On Jan. 31, Kyrgyzstan authorities identified a train car carrying Cesium-137 en route to Iran. Authorities have documented cases of the loss, misappropriation and/or theft of various radioactive sources over the years. Needless to say, a successful nuclear detonation would be catastrophic. Even the panic associated with the threat of a nuclear device could be significant enough to cause economic disruption on a scale as broad and deep as Sept. 11.”
Authorities are currently using point-source detectors at seaports or borders to guard against nuclear material. A ring of detectors is being installed around New York City, but the system can sweep the entire city only once every two hours. These measures are woefully inadequate.
The solution? Equip every cell phone with a nuclear detector and enlist the help of civilians. That’s what Purdue researchers believe will do the job — effectively and inexpensively.
How it works
The researchers plan to embed small, low-cost radiation sensors into cell phones, converting them into nuclear detectors. Since most cell phones already contain global positioning (GPS) technology, it’s possible to easily utilize the existing infrastructure to set up a nationwide radiological tracking system.
Every such modified cell phone would act as one node in a sensor network, detect any radiation residue and automatically report the event to a data center, without even alerting the person carrying the phone. A person could help prevent terrorist attacks just by carrying a sensor-equipped phone without even being aware of it.
“The sensors don’t really perform the detection task individually,” said Ephraim Fischbach, professor of Physics at Purdue who is working on the system along with Jere Jenkins, director of Purdue’s radiation laboratories. “The collective action of the sensors, combined with the software analysis, detects the source. The system would transmit signals to a data center, and the data center would transmit information to authorities without alerting the person carrying the phone.
“Say a car is transporting radioactive material for a bomb, and that car is driving down Meridian Street in Indianapolis or Fifth Avenue in New York. As the carpasses people, their cell phones individually would send signals to a command center, allowing authorities to track the source.”
The software is capable of using the data received from the cell phones to precisely pinpoint the location of the nuclear weapon and transmit it in real time to viewable GPS-linked maps that military and security personnel can use.
Since the signal would grow weaker with increasing distance from the source, it would indicate how close or how far away the weapon was. The signal’s speed, the researchers say, would depend on how many phones contained the sensors—the greater the number of phones, the faster and more accurate the response.
“If every person in New York City who carries a cell phone had our system working, a terrorist smuggling a Hiroshima bomb into Manhattan would be instantly seen and tracked before he could get anywhere—it would be minutes to seconds before he was identified,” observed Longman. “Individuals would not be reporting; their phones would be sending statistical data all the time. No one phone would be essential, nor would any one phone perform the detection action. Rather, the constellation of phones would provide data to the software, and the software would ‘detect’ the weapon.”
In an initial test funded by the Indiana Department of Transportation, the system detected a radiation source at a distance of 15 feet and pinpointed the exact location of the “bomb.” It can also be used to detect spills of radioactive materials and is sensitive enough to ignore known radiation sources, such as hospitals, or radiation from other sources that don’t pose any potential threats. The team hopes that the technology will eventually become ubiquitous and be built into laptops and personal digital assistants, in addition to cell phones.
Setting up the system
All that needs to be done to set up the system is to incorporate some inexpensive lightweight sensors into the phones now being manufactured. Researchers are urging the public to strongly push for this scenario. They say it is possible to set up an extremely comprehensive and effective network, with the right partnerships, within three to five years, where people could help authorities catch terrorists just by carrying a digital product.
“Imagine being a terrorist, and carrying an 80-kilogram back pack, trying to walk up the street in New York City and avoid every person with a cell phone by 5 meters, or imagine a terrorist driving a Toyota with 1,200 kilograms worth of bomb in back, trying to avoid crushes of 50 people at crosswalks — not likely,” said Longman. “If our system was in place, we could force the terrorists to go to such extremes to try to shield the bomb that we could then do things like regulate and scan very heavy lorries [trucks], and thereby limit their options. The public needs to lay aside emotional fears. Having a nuclear detector in your phone makes you safer, period. It combats terrorism. It will save many lives if implemented.”