Japan 'Moon Sniper' lands but 'not generating power'

Japan on Saturday became only the fifth nation to achieve a soft Moon landing, but the craft's long-term fate was in doubt after space agency officials said its solar cells were not generating power.

Why quantum mechanics defies physics

The full, weird story of the quantum world is much too large for a single article, but the period from 1905, when Einstein first published his solution to the photoelectric puzzle, to the 1960s, when a complete, well-tested, ...

Japan moon lander enters lunar orbit

Japan's SLIM space probe entered the moon's orbit on Monday in a major step towards the country's first successful lunar landing, expected next month.

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Ball

A ball is a round, usually spherical but sometimes ovoid, object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch, marbles and juggling. Balls made from hard-wearing materials are used in engineering applications to provide very low friction bearings, known as ball bearings. Black powder weapons use stone and metal balls as projectiles.

Although many types of balls are today made from rubber, this form was unknown outside the Americas until after the voyages of Columbus. The Spanish were the first Europeans to see bouncing rubber balls (albeit solid and not inflated) which were employed most notably in the Mesoamerican ballgame. Balls used in various sports in other parts of the world prior to Columbus were made from other materials such as animal bladders or skins, stuffed with various materials.

As balls are one of the most familiar spherical objects to humans, the word "ball" is used to refer to, or to describe, anything spherical or near-spherical.

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