So he starts by measuring the speed at which his subjects, vertigo patients all, actually register motion.

ECONOMIST: Vertigo: A new kind of pacemaker | The

When it's bolted onto the Blanco Telescope at the Cerro Tolodo Observatory in Chile next month the 570-megapixel Dark Energy Camera will survey some 300 million galaxies in the southern sky, measuring the speed at which they are moving apart with phenomenal accuracy, and giving the best description yet of the accelerating expansion of the Universe.

BBC: Getting the measure of dark energy

Many athletes use Strava to rank their own performances over time, measuring not only speed and distance but also heart rate, power output and other information.

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But a variant of the technique, which involves measuring changes in the speed of the reflected wave, can reveal information about moisture.

ECONOMIST: Winemaking and radar

"We're measuring the zero-to-60 speed but also the gas mileage, " says Lankford.

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