When new employees come to work at the Boeing production facility in Everett, Washington, one of their first stops is often an exhibition at the company’s Safety Experience Center. It opens on a sombre note: a memorial for famous air disasters, including the successive crashes of two 737 MAXs, in 2018 and 2019, in the Java Sea and Ethiopia. Then, gradually, the tone grows more hopeful. At Boeing, as throughout the aviation industry, disasters led to innovations. Oxygen masks and electronic anti-skid brakes were introduced in the nineteen-sixties, along with bird cannons at airports, to shoo off Canada geese and fellow-fliers. Overhead bins got latched doors that same decade, to keep luggage from toppling onto passengers’ heads. Satellite communication came along in the seventies; automated flight-management systems, capable of plotting a plane’s course, speed, and altitude, in the eighties. Radar systems got more accurate; planes grew stronger, sleeker, and more flexible. Pilots got better at skirting turbulence—or, if they couldn’t, at slowing down and “riding the bumps.”
The sun is a giant nuclear fusion reactor, converting hydrogen into helium and releasing massive amounts of energy in the form of heat – and sound. Sound is essentially vibration and needs a medium to travel through.
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The SETBLOCK function will coalesce all free blocks that immediately follow the memory block being resized (even if the new size is the same or smaller).