Space: The Payoff Was Perfection

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Pictures by Earthlight. One after another, the pictures showed that Surveyor was standing on a broad, relatively level plain littered with pebbles as small as one-eighth of an inch in diameter and rocks that were more than a foot across. The terrain was pocked by an occasional small crater, and one picture clearly showed a hump on the horizon that is believed to be either a crater rim or a low hill. A view of one of Surveyor's feet showed that its impact had dented the surface a few inches, indicating to some scientists that the site had the consistency of a terrestrial ocean beach.

To learn more about the lunar surface, JPL scientists decided to fire the small attitude-control thrusters located near the bottom of each of Surveyor's three legs, less than a foot above the surface. Seven different times, the thrusters fired jets of nitrogen into the lunar soil while Surveyor's camera shot pictures of the area near its feet. The pictures showed no clouds of dust—another indication that the lunar surface is firmly packed. By week's end, as the sun rose toward its apex in the lunar sky, shortening shadows and making it more difficult to distinguish lunar objects, Surveyor had already taken and transmitted more than 2,000 pictures. Because Surveyor landed in the morning of the two-week lunar daytime, period, its TV camera should be able to operate for about twelve days, powered by batteries that will be constantly recharged by solar cells. By shooting the reflections from a mirror that can rotate 360° and tilt up and down, the fixed camera can televise views from Surveyor's feet to above the horizon a mile away. As the lunar night descends, the batteries should remain charged long enough for the camera to take a picture of the lunar landscape, faintly illuminated by earthlight.

Shuffling the Standings. After a plague of misfortune and mismanagement had put it three years behind schedule, the Surveyor success was doubly sweet. Equipment broke down during tests and had to be redesigned. The second-stage Centaur—the first liquid-hydrogen rocket—had several mishaps and had flown only one completely successful mission before last week's shot. Summarizing the program, the House Space Committee characterized it as "one of the least orderly and most poorly executed NASA projects."

Yet last week, the clouds over Surveyor all seemed to dissipate. The Atlas-Centaur rocket that hurled Surveyor toward the moon was only one second late in leaving the pad; it followed a near-perfect trajectory that would have placed Surveyor only 250 miles from its target on the moon. The mid-course correction was so accurate that Surveyor actually scored an effective bull's-eye. Only one "glitch" marred the performance: one of Surveyor's two antennas failed to extend fully after the craft left the earth's atmosphere. But even this problem corrected itself. When Surveyor hit the moon, the modest jolt snapped the antenna into place.

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