You're a soldier on patrol in Afghanistan. Walking down the road, you spot a strange object far away, sticking out off to the side. Is it a bomb? How should you even check? If the Army's latest research project pans out, you might just whip out your paintball gun.

On Wednesday, the Army announced that it's in the market for a paintball system that can detect the presence and type of different explosives. The system would work by loading up projectiles with materials that advertise the presence of explosives – sort of like a litmus test for bombs – and firing them at the suspected bombs. Picture paintballing, but with a target that might really kill you.

It's another foray into the field of bomb-hunting technology. Over the past few years, scientists have developed a range of weird and wonderful ways to sniff out the things that go boom, from explosives-sensitive plants to dynamite-detecting bee venom. But for maximum safety, it's always nice to figure out if that package or object is a bomb when you're not close enough to be blown apart by it.

That's standoff explosive detection, a field the Defense Department has shown great interest in as terrorists and insurgents have become better and more frequent users of improvised explosive devices. The Pentagon has put cash into a number of different approaches, using lasers and terahertz radiation to find traces of explosive material.

The paintball idea is comparatively low-tech. The Army notes that the technology to detect explosives with paints and powders is already a commercial reality. They point to Raptor Detection Technology's SAFE-T Spray, which turns orange on contact with certain explosives, as an example.

So fill up some paintballs with bomb-detecting goop and fire away, right? It's a little more complicated than that.

The challenge for the paintball system comes from distance. As you might guess, the greater distance you can put between yourself and a bomb, the better. But with distance comes visibility and accuracy problems.

The Army's looking for a system that works on targets up to 100 meters away. At that distance, it can be hard to see the tiny smear from a paintball, which usually holds about 2.5 milliliters worth of paint. Those pitching the Army need to make a system that fires a larger amount of detection material and one that spreads it out further on contact than the standard neon paintball blotch. Ultimately, it has to be visible from 100 meters without the help of binoculars.

But that's only if you can get your paintball on target. Anyone who's cursed the gods as their quarry has run through the field unpainted despite firing a barrage of paintballs knows that many paintball guns just aren't very accurate. They often don't have rifled barrels or other ways of putting a spin on their projectiles. Rifling spins a projectile as it's fired, giving it greater accuracy over distance. The Army's aiming for a system that will be accurate up to the 100-meter distance.

Just don't put too much power behind that shot. The Army doesn't want its remote bomb detector gun to accidentally double as remote bomb detonator.

Photo: dvidshub