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One Apollo 11 Experiment Is Still Going 50 Years Later

The Lunar Laser Ranging Experiment lets NASA precisely measure the distance between Earth and the moon

5 min read
Image of the laser deployed from the facility and pointing toward the sky.
Goddard’s Laser Ranging Facility in Greenbelt, Md., directing a laser (green beam) toward the Lunar Reconnaissance Orbiter spacecraft in orbit around the moon (white disk). The moon has been deliberately over-exposed to show the laser.
Photo: Tom Zagwodzki/Goddard Space Flight Center

THE INSTITUTEIf nothing else will convince someone that humans once walked on the moon, NASA’s lunar ranging experiment (LURE) should. It’s because of that experiment that scientists know the precise distance between the Earth and the moon with centimeter accuracy.

The LURE’s first demonstration began on 1 August 1969, when a pulse of trillions of photons was shot out of a telescope at Lick Observatory on Mount Hamilton, outside of San Jose, Calif. The laser pulse traveled to the moon and returned after reflecting off a 1-meter-wide array of mirrors—retroreflectors—that Apollo 11 astronauts had placed on the lunar surface 12 days earlier.

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The Lies that Powered the Invention of Pong

A fake contract masked a design exercise–and started an industry

4 min read
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Pong arcade game in yellow cabinet containing black and white TV display, two knobs are labeled Player 1 and Player 2, Atari logo visible.
Roger Garfield/Alamy

In 1971 video games were played in computer science laboratories when the professors were not looking—and in very few other places. In 1973 millions of people in the United States and millions of others around the world had seen at least one video game in action. That game was Pong.

Two electrical engineers were responsible for putting this game in the hands of the public—Nolan Bushnell and Allan Alcorn, both of whom, with Ted Dabney, started Atari Inc. in Sunnyvale, Calif. Mr. Bushnell told Mr. Alcorn that Atari had a contract from General Electric Co. to design a consumer product. Mr. Bushnell suggested a Ping-Pong game with a ball, two paddles, and a score, that could be played on a television.

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