Astrophysics fighting terrorism

Reported here:

The first part of McLean's project is to create a specialized chip that turns a semiconducting crystal into a detector that can find a radiation source up to 100 meters away and tell whether it's harmful radiation from a dirty bomb, or harmless radiation from, say, a truckload of fertilizer. In the second phase, which could begin by the middle of 2006, he'll build a workable device.

The problem with current detectors is that they are often set off by essentially benign materials. They also tend to be large pieces of equipment located only at the nation's entry points, such as ports.

McLean wants to make detectors that will ignore natural radiation sources like fertilizer and that will also be small and mobile, so that security officers can take them anywhere and target any ship, truck, or building.

First, a "truck load of fertilizer"- as we have come to know- may not be harmless. Second, I hope this is more than a BS detector.