Word: hydrogen
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Dates: during 1960-1969
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Nature's most catastrophic events are supernovae-rare stars that burst with a brilliance 100 million times more luminous than the sun, releasing the equivalent of 200 trillion trillion 100-megaton hydrogen bombs. Swiss Astronomer Paul Wild has just added a new one to the stellar log-the first supernova seen from the earth in the unnamed galaxy N.G.C. 4189 in the constellation Virgo...
...supernova's own gigantic size is its undoing. Astrophysicist Subrahmanyan Chandrasekhar calculated that a star whose mass is greater than 1.44 times the sun's mass cannot follow normal stellar evolution. Over a few million years, burning hydrogen on the outer layers of such a star produces more and more helium at its core. The doomed star's interior shrinks rapidly; and the density of its core increases. As temperatures rise in the contracting core, the collected helium is converted into successively heavier elements, such as iron and gold, which crowd the lighter elements outward...
Inside the buildings, the electron beam is fired at targets such as metallic sheets or containers of liquid hydrogen. As a high-energy electron approaches the nucleus of an atom in the target, one of two things happens: it veers off in a different direction, or it actually shatters the nucleus-and the reaction often produces new and different particles that exist for only billionths of a second...
...Sloshing. Then, with the SIV B in orbit and its engine shut down, the TV screens showed a weird transformation in the fuel tank. Now weightless, globules of liquid hydrogen ripped loose from the churning surface and began to drift upward. Ground controllers immediately radioed signals that opened the SIV B's tank vents, allowing escaping gases to accelerate the vehicle slightly. On the screen, the globs could be seen obediently settling back to the surface. "It looks calm," the controllers reported. "It's behaving itself. There's no sloshing...
With its tank vents still spewing tiny jets of gas, the slowly accelerating SIV B was then put through a simulated engine restart. Valves at the bottom of the tank opened, allowing liquid hydrogen to flow into the combustion chamber. Clearly visible on TV, the dwindling fuel hugged the bottom of the tank, its surface calm...