In chemistry, the atom is the most fundamental building block of matter. Now the automotive world has its atom -- a car so pure and simple that some people are calling it minimalist art. But the Atom, designed by Ariel Motor Company of Great Britain, is not something you enjoy from a distance. To truly experience it, you must climb into the two-seat cockpit, start the engine and punch the accelerator.

Those that have describe the Atom as one of the most amazing automobiles in recent history. Sunday Times columnist (and host of BBC's "Top Gear") Jeremy Clarkson gave the Atom five stars and said, "In terms of sheer thrills, the Atom is easily a match for the Porsche Carrera GT...This car is motoring nirvana."

Exotic Car Image Gallery

Image courtesy Brammo Motorsports / Ariel Atom See more exotic car pictures.

In this article, we'll look at how the Atom works and why car enthusiasts, including celebrity thrill-seeker Jay Leno, are chomping at the bit to have one in their garage.

Thank You Thanks to Jeff Beckman for his assistance with this article.

Strictly speaking, the Atom is a supercar, a type of sports car made in relatively low numbers and with high-performance features that rival racecars. Even with their exotic look and superlative performance, supercars are generally designed to be street-legal. But it's on the track, where speed limits and traffic laws don't apply, that supercars truly shine.

Image courtesy Brammo Motorsports / Ariel Atom

Virtually all supercars accelerate from zero to 60 mph in under four seconds and can reach top speeds of 180 mph or faster. A low weight-to-power ratio (pounds per horsepower) makes this kind of performance possible. Remember Newton's first law of motion? It describes inertia -- the tendency of an object to remain at rest or an object in motion to remain in motion unless acted upon by an unbalanced force. The more mass an object has, the more inertia it has; the more it will resist changes in its motion. That's why super-lightweight cars have such high acceleration. Their lower inertia makes them easier to move, especially when a 250-horsepower engine is generating the force causing the motion.

So how does the Atom stack up to other supercars when measured against key performance criteria? First, the Atom weighs just a little more than 1,000 pounds and comes with an engine that generates up to 300 horsepower. In contrast, a Lincoln Town Car weighs up to 4,500 pounds and has a 239-horsepower engine, resulting in a weight-to-power ratio of 19 to 1. As the table below shows, the maximum weight-to-power ratio of the Atom is far below a Town Car's -- and is among the lowest of all supercars.

Car	Weight-to-Power Ratio	0-60 Acceleration (s)	Top Speed (mph)
McLaren F1	4.01 to 1	3.2	240
Bugatti Veyron	4.35 to 1	2.5	252
Ferrari Enzo	4.56 to 1	3.5	217
Porsche Carrera GT	4.97 to 1	3.8	205
Ariel Atom	4.10 to 1	2.8	135

The Atom's acceleration also stands out. Based on its phenomenal zero-to-60 performance, it has won the distinction of fastest production car in the world. The one supercar attribute you won't find on the Atom, however, is a six-figure price tag. It ranges from $35,000 to $75,000 -- a pittance when compared to the McLaren F1 or Bugatti Veyron, both of which carry $1 million price tags. Even the Porsche Carrera GT, priced at $440,000, costs almost six times as much as the Atom.

Although the Atom meets the performance criteria of the supercar category, it doesn't look like a typical sports car. That's because Formula One racers inspired its engineering. It has a nose cone, a low, wide shape and an engine mounted behind the driver, who is exposed to the elements because the vehicle lacks doors, a windshield or a roof. To help produce downward force on the vehicle, the Atom has a rear wing that also serves as an engine cover.

Image courtesy Brammo Motorsports / Ariel Atom

From a distance, the Atom even looks a little like a Cooper Formula One racing car. But unlike a true racer, the Atom isn't confined to the track. It is equally at home on the highway -- and in the car enthusiast's garage. That's because the Atom doesn't require a team of professional mechanics to keep the car tweaked and tuned. It's easy to drive, easy to maintain and economical to own. In the next section, we'll see how the Atom pulls it off.

Is the Atom really street-legal? If the Atom looks like a racecar and runs like a racecar, is it really legal to drive one on U.S. highways? First, let's define "street-legal." Street-legal simply means that a car meets certain government standards for motor vehicle safety. The National Highway Traffic Safety Administration (NHTSA) establishes and enforces these standards at the federal level. States may impose additional laws or regulations that further govern what vehicles are allowed on the road. To be street-legal, an Atom must be built as a kit car. That means everything, including the engine, is shipped to the owner in pieces. An optional road pack, which includes turn signals, a horn, rear tail lights and headlamps, is also available. The owner assembles the car in his own garage, being sure to follow all appropriate, state-mandated vehicle safety guidelines. Otherwise, the Atom is sold as an off-the-road-only vehicle -- not legal on the highway, but perfectly comfortable at the local track.