National Geographic : 1966 Oct
Surveyor: Candid Camera on the Moon legs spread wide, Surveyor fell the last 13 feet with half the speed of a parachute jumper approximately 10 feet a second (page 580). The three-legged robot, weighing about 600 pounds on earth but only about 100 in the moon's lower gravity, bounced slightly, oscil lated briefly as its shock absorbers settled, and came to rest undamaged. Its footpads, 12-inch-diameter disks of crushable alumi num honeycomb, dug about an inch into the lunar surface. At impact, the tubular aluminum legs pivoted to absorb shock, and crushable pads under the "knees" of the legs sank momentar ily into the surface. One of the prints shows clearly in the picture at the top of page 588. What Surveyor saw after it landed was, of course, not totally new. Three Ranger space craft had sent back pictures just before crash ing into the moon's face.* Russia's Luna 9 landed on the moon last February and took a handful of close-up photographs. But Surveyor saw with a sharper and clear er eye. And, for the first time, it saw in color. Three separate photographs, taken with orange, green, and blue filters, combined to produce a fairly accurate color representa The author: Space scientist Homer E. Newell directs NASA's unmanned flights as Associate Administrator for Space Science and Applications. Information gleaned by his space scouts-Mariners, Rangers, Sur veyors, Lunar Orbiters, and others-paves the way for manned voyages. unus,. av E)II.nll.. U., - tion. As scientists expected, that color seems to be nothing but gray-a plain, neutral gray. Surveyor had but a single eye, its TV cam era. Instead of turning this eye about, it gazed upward at a motor-driven mirror that, on radio command from earth, searched the ground below or scanned the horizon in al most a full circle (painting, page 590). The camera saw approximately as far as a man's eye would see, since the mirror was about 5 V2 feet above the surface. The horizon, because of the small diameter and sharp cur vature of the moon, lay only about a mile away. On earth the horizon would have been roughly four miles distant. And what did Surveyor see in the Ocean of Storms? It found itself in a shallow crater some 60 miles across. It had landed on a dark, level, relatively smooth spot. Low-lying hills and mountains of the crater's rim, at least 10 miles distant, poked their crests above the horizon (page 582). Surveyor Settles an Old Controversy In every direction stretched an eerie waste land, scarred with smaller craters from an inch to several hundred feet across and lit tered with debris. Coarse blocks of rock as wide as three feet and countless smaller frag ments lay strewn upon the crater lips and the surrounding areas. The blocks and fragments represent debris ejected by the constant barrage of meteorites cratering the moon's surface, or rubble thrown out of secondary craters created by the impact of the original flying debris. By the time you read this, if all goes well, Surveyor I will have been followed by Sur veyor II, next in a series of 10 planned mis sions. These will examine potential Apollo landing sites and survey other areas. Lunar Orbiter I also may have flown, whirl ing round the moon to obtain photographs at altitudes as low as 30 miles and transmit back to earth pictures of potential Apollo and Surveyor landing zones (page 592). But so well did our first lunar soft-lander work that many scientists doubt that its successors will radically change our impression of the surface of the moon's vast "ocean" plains. Before Surveyor I's voyage, scientists had engaged in intense speculation and prolonged controversy over the nature of the moon's face. Some argued firmly that the moon was *See "The Moon Close Up," by Eugene M. Shoemaker, NATIONAL GEOGRAPHIC, November, 1964.