Roger Linfield and his colleagues at the Jet Propulsion Laboratory in Pasadena, California, who are in charge of the mission, aim to show that spacecraft flying in formation can be controlled so precisely that the distance between them varies by only a tiny fraction of a wavelength of light.

ECONOMIST: Birds of a feather

Central European time from Manching Air Base and climbed to a ceiling of 54, 000 feet within military controlled airspace, far above and at a safe distance from civilian air traffic.

ENGADGET: Northrop Grumman, Cassidian run Euro Hawk UAV through its first full test flight (video)

The GALAXY Camera's 21x optical zoom can be controlled by either button or touchscreen, rendering long-distance pictures in a quality that users will be proud to share, while OIS ensures that images stay clear and crisp.

ENGADGET: Samsung announces EK-GC100 Galaxy Camera with Android Jelly Bean, massive 4.8-inch display, 21x zoom, WiFi and 4G connectivity (hands-on)

Events like the Tough Guy and Tough Mudder are tightly controlled for safety reasons, but as with ordinary long-distance running there are injuries.

BBC: From marathons to mud running

Our correspondent says he has heard a few explosions in the distance, but they are believed to have been controlled detonations of IEDs.

BBC: Afghanistan: Nato launches major anti-Taliban offensive

"You'll arrive in a town - and there will be a signal sent to your car not to exceed a maximum speed, and you won't be able to, and distance to the car in front will also be controlled, " he said.

BBC: Nissan car drives and parks itself at Ceatec

Even after selecting Mr. Ryan, the Romney team has kept some distance from the details of the Ryan budget, which has been backed by the Republican-controlled House.

WSJ: Ryan Selection Sets Off Debate on Government