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A model of the Ohio team鈥檚 nanocar (Image: CNRS)

You鈥檝e never seen a race like this before. In fact, no one has, because the cars are too small to see with the naked eye.

This November, scientists from around the world will meet in Toulouse, France, for a world first: a car race conducted at the nanoscopic level. The race will test the capabilities of molecular machines which pave the way for future devices, ones that can practice medicine inside our bodies, or help us build computers.

There are five teams slated to compete, from France, the US, Austria, Germany and Japan (see box below). Each one鈥檚 nanocar is different: some are like macroscopic automobiles, with four wheels, axles, chassis and a small 鈥渕otor鈥�. Others have parts custom-designed for the car鈥檚 tiny environment. Even the largest is just a few nanometres long 鈥� a little .

Buckyball wheels

The nanocar鈥檚 origin dates to 2005, in James Tour鈥檚 lab at Rice University in Houston, Texas. Three or 4 nanometres long, it had buckyball wheels connected with axles and a chassis. It was made through a series of chemical reactions, producing a billion billion cars at a time.

鈥淣o one had really figured out how to construct something like that, how to have wheels that could truly rotate. All of that had to be worked out,鈥� says Tour.

The Texas/Austria team鈥檚 nanocar (Image: CNRS)

More types of tiny cars and other vehicles have since been developed. At the Leibniz Institute for Solid State and Metals Research in Dresden, Germany, scientists made platinum-coated 鈥�nanorockets鈥� that shoot through a sea of hydrogen peroxide at 200 times their length per second. In November, Tour鈥檚 lab unveiled a 鈥溾��, with molecular motors powered by ultraviolet light.

Race towards tiny

The vision driving the builders of these tiny vehicles is to figure out what it takes to build machines that can do our bidding on a microscopic level. 鈥淭echnology is moving towards making smaller and smaller devices,鈥� says Henry Hess, a biomedical engineer at Columbia University in New York City.

Hess thinks the nanocar race will spur the science to progress more quickly, like the DARPA Robotics Challenge or the X-Prizes. He鈥檚 excited about potential medical applications: nanotransporters that could detect pathogens in a cell and carry them over to a tiny sensor, for example, or a nanoscale factory that produces useful molecules and ships them where they need to go, 鈥渓ike delivery trucks in a city鈥�.

Computer-builders

Tour compares the technology to red blood cells ferrying oxygen around the body, or fire ants working in concert to build a mound of dirt overnight. He envisions nanocars carrying raw materials to build tiny, useful structures for us from the ground up. They could pile metal atoms up to build bits of a computer, eventually precisely building up to objects that we could actually see with our eyes.

鈥淭his nanocar race is going to be child鈥檚 play compared to the things that will be demonstrated in the next century,鈥� he says. 鈥淧eople will look back on this and kind of laugh, like when we look back on the very early versions of automobiles.鈥�

How to drive a clump of atoms

Last November, the teams met in Toulouse to present their cars and discuss the rules for the race. Here how it will go: The teams will drop their cars onto a crystalline gold surface, kept in an ultra-high vacuum at a chilly -268 掳C. The track has a starting line, finish line, and obstacles marked by individual gold atoms. Each team will have a designated 鈥渄river鈥�, whose job is to find the car on the surface and navigate it from start to finish.

That description makes the process sound simple. It isn鈥檛. The teams will have spent months or years optimising their cars. One surprising challenge is just picking up and moving the cars, from labs around the world to Toulouse, then onto the gold surface.

Powdered cars

The scale is massive. Picking out one of your nanocars on the field like trying to find two or three normal cars on a map of the US, explains Saw Hla at Ohio University, co-leader of the . His team plans to transport their cars from the lab to the race as a purified powder, then vaporised them so a few will stick to the gold.

Once Hla and the competitors spot one of their cars, they鈥檒l have to coax it over to a track. Then, it鈥檚 time to drive. On campus, the CNRS has a scanning tunnelling microscope, an instrument that can image and interact with objects at the atomic level. It comes equipped with four needles that can be used to zap a car with electricity, powering the car to move in the desired direction. Manually pushing or pulling the car is forbidden.

Nano Formula 1

Once moving, the nanocars are fairly fast. One team quoted it at 鈥渁bout 10 nanomiles per hour鈥�, or roughly 10 nanocar lengths per second, the equivalent of a normal car going 170 kilometres per hour. The teams will have two days and two nights to try to win.

Hess says the race, and the competitive environment, will help the teams improve their cars. In the lab, he says, it鈥檚 easy to lose sight of your product鈥檚 shortcomings. 鈥淚n the same ways as the Formula 1 races may help the development of cars, here the same thing may occur. The push to win the race may make you think about a lot of aspects of your system beyond just the speed.鈥�

Another admitted goal of the race: to attract public curiosity to the world of nanoscience. 鈥淭his is a very beautiful idea behind it, is that this may actually to make people interested in nanoscale transport,鈥� says Hla.