Manual docking requires astronauts to have a precise judgement on the relative distance between Shenzhou IX and the Tiangong-1 module, a challenge to their capability of coordination, accuracy and psychological stability.

FORBES: China's Space Age Grows Up As U.S. Space Race Winds Down

The Germans and other allies wish to sell the Soviet Union and other Warsaw Pact nations machine tools with the capability of producing, for example, advanced aviation components with an accuracy of plus-or-minus five microns (two ten-thousandths of an inch) or better.

CENTERFORSECURITYPOLICY: Center For Security Policy

The capability to strike at very long range with very great accuracy using conventional weapons has been a goal of strategic air power since the invention of the airplane.

CENTERFORSECURITYPOLICY: Center For Security Policy