Space Chronicles by Neil DeGrasse Tyson

Author:Neil DeGrasse Tyson
Language: eng
Format: epub
Publisher: W. W. Norton & Company
Published: 2012-01-29T16:00:00+00:00

A trip to the Moon through the vacuum of space had been in sight, even if technologically distant, ever since 1926, when Robert Goddard perfected liquid-fuel rockets. This advance in rocketry made flight possible without the lift provided by air moving over a wing. Goddard himself realized that a trip to the Moon was finally possible but that it might be prohibitively expensive. “It might cost a million dollars,” he once mused.

Calculations that were possible the day after Isaac Newton wrote down his universal law of gravitation show that an efficient trip to the Moon—in a craft escaping Earth’s atmosphere at a speed of seven miles per second, and coasting the rest of the way—takes about three days. Such a trip has been taken only nine times—all of them between 1968 and 1972. Other than those nine trips, when NASA sends astronauts into “space” it launches a crew into orbit a few hundred miles above our eight-thousand-mile-diameter planet. Space travel this isn’t.

What if you had told John Glenn, following his historic three orbits and successful splashdown in 1962, that thirty-seven years later NASA would send him into space again? You can bet he would never have imagined that the best we could do would be to send him back into low Earth orbit.

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