Giant Step for Lunokhod

The image that flickered onto Moscow TV screens last week showed an awkward, eight-wheeled contraption that looked somewhat like the top half of a huge samovar. But what the outlandish vehicle lacked in styling, it more than made up for in performance. Three hours after reaching the moon aboard the latest unmanned Russian moon probe, Luna 17, Lunokhod I (literally "moonwalker") lumbered down one of two ramps extended by the mother ship and moved forward under the direct control of TV monitors on earth--thus taking the first giant step for robotkind on another celestial body.

The Soviets were understandably exultant. "The flight of Luna 17 signifies the start of a new stage in the study of the moon," said Radio Moscow. U.S. space officials saw no reason to disagree. "Just fantastic," said one NASA scientist. His boss, Acting NASA Chief George Low, noted that the Russians had launched 22 space missions in the past two months alone--earth satellites as well as two moon shots. With the addition of Luna 17 to the list, he said, it is clear that the Soviet Union is "operating with an advanced state of technology and is exploiting it for a broad range of objectives."

Vague Hints. Luna 17 landed on the unexplored Sea of Rains, one of the oldest lunar maria. It lies some 1,400 miles northwest of the Sea of Fertility, where Luna 16 landed two months ago to scoop up 3.5 oz. of moon dust for later study on earth. At first, the Russians gave only the vaguest hints about Luna 17's mission. But once the rover demonstrated its maneuvering ability, they began revealing details of their moon machine.

Lunokhod is powered by solar cells that are apparently charged when it opens its clamlike lid to sunlight. One or more electric motors drive each of the eight spoked wheels independently. Like a remote-controlled toy car, it is steered by radio signals from earth, where monitors are able to see the terrain in front, behind and to the side of the rover in pictures transmitted from onboard TV cameras. To avert disabling accidents, Lunokhod has a number of safety features. It can, for instance, shut itself off if it begins to list dangerously, or if one of its wheels becomes stuck in a lunar rut. If the wheel cannot be worked free, the ground controllers can fire a small explosive charge, disconnecting it from the drive shaft and allowing it to spin freely. In fact, the vehicle can move either forward or backward with two wheels out of action on each side.

Lunar Mapping. One thing Lunokhod cannot do is come back to earth. Even though it was built of extremely light materials, its undisclosed weight is apparently too great for the lift-off capability of Luna 17. In that respect, Lunokhod resembles NASA's own lunar rover,* which will be carried to the moon by Apollo 15.

By the third day, Lunokhod had moved confidently across at least 600 ft. of lunar soil, turned to photograph the mother ship, climbed up an incline and crossed a small crater. The robot also displayed impressive scientific skills. Like Luna 16, it carries a device to gouge out samples of lunar soil. It also has the capacity to analyze samples --with an onboard X-ray spectrometer --and report the findings to earth. In addition, it can detect cosmic rays, stomp on the ground to test its rigidity and--speculates Heinz Kaminski of West Germany's Bochum Observatory, where the radio transmissions from Russian space shots are carefully monitored --take three-dimensional pictures of the lunar surface with its multiple cameras for making maps of the moon.

Distant Landscapes. The Russians also made a bow to international cooperation in space. Lunokhod carried a French-built array of 14 corner-shaped mirrors designed to reflect long-distance laser beams from observatories in southern France and the Crimea. A similar reflector left behind by Apollo 11 on the Sea of Tranquility has already enabled U.S. scientists to measure the distance between earth and moon with an accuracy of less than a foot. Indeed, U.S. observers think that the Soviets might be interested in testing such a device as a means of navigating future moon robots.

By week's end Lunokhod had clearly lived up to Soviet expectations. To cope with the frigid temperatures of the approaching two-week-long lunar night, the Russians will probably power down the vehicle, allowing it to "hibernate" until it can again draw energy from the sun. If it survives the extreme cold ( --250DEGF.), Kaminski predicted, it might well resume its explorations, eventually traveling hundreds of miles from the landing site--provided no other calamity befalls it. The Russians themselves were not inclined to make any risky predictions. But they did say that in the future more advanced robots--so-called planetokhods--would explore not only the moon but more distant landscapes on Mars, Venus and Mercury.

* A model of the U.S. machine arrived in Houston last week for training purposes. The 800-lb. vehicle resembles a terrestrial dune buggy, and is scheduled to carry two Apollo 15 astronauts on a short test spin across the lunar surface next summer.

This file is automatically generated by a robot program, so reader's discretion is required.