The Other Moon Landings
The Soviets lost the moon race but won a dram of glory with the first robotic craft to roam another world.
- By Andrew Chaikin
- Air & Space magazine, March 2004
NASA History Office
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Gripping in his right hand a control stick that resembled a car’s gearshift, Latypov could make the rover go forward at one of two speeds (0.5 or 1.2 mph) or go in reverse. He and Vyacheslav Dovgan, the other crew’s driver, turned the craft not by rotating the wheels, which were fixed, but by slowing down one side relative to the other, the way one steers a tank.
Latypov and Dovgan’s only guidance came from a monitor, which displayed images from Lunokhod’s two low-resolution television cameras. To any video game enthusiast it sounds simple—but this was nothing like a video game. The cameras did not send a continuous stream of images, but rather single frames, like a slide show, at intervals that varied from seven to 20 seconds. And because radio signals took three seconds to travel round trip between Earth and the moon, the driver didn’t see the results of his actions for many long moments. For this reason, if crew commanders Nikolai Yeremenko and Igor Fyodorov saw Lunokhod heading toward catastrophe, they could push a button to halt the rover.
Dovgan, now 66, was well prepared by intensive training. “Driving on the moon felt even easier than it was in the lunodrome,” he says, but his comment belies the difficulties of navigating the rover. The low resolution of the slide show made it difficult to spot craters and boulders, especially at high sun angles, and there was a “dead zone”—a three-foot-wide area immediately in front of the rover that Lunokhod’s cameras could not see. The only solution, according to Dogvan, was to memorize the features in this area from the previous image, before the rover reached it. “When we were looking ahead and thinking of the obstacles that we did see, we also had to remember what was just behind,” he says.
Dovgan also had to constantly verbalize what he saw to Fyodorov. “103,” Dovgan would say, using the commander’s call sign, “this is 101 reporting on the situation. Twenty degrees left of the course, a stone; distance, five meters; height, 35 [centimeters], width, 50. Straight ahead, a crater, diameter, nine meters. To the right, 15 degrees, a gap. Decision: Will turn left 60 degrees to avoid both crater and stone, and then regain the straight-ahead direction.” Although Fyodorov sometimes challenged Dovgan before approving his plans, he ultimately trusted his driver’s judgment as if Dovgan were actually on the moon. And indeed, Dovgan sometimes felt as if he were. “Not that I forgot that I was on Earth, but it felt like I was so phased into my work that the only thing that wasn’t part of me being on the moon was the constant, continuous reporting,” he recalls. “It almost felt like I was talking to myself all the time, or that I was talking to Lunokhod.”
Unlike cosmonauts of the day, Dovgan and crewmates were unknown to the Soviet public and under strict orders not to talk about their work. For Dovgan, who grew up in Simferopol, the secrecy was especially tough. “I couldn’t even tell my friends,” he recalls. “And you know, all my friends were there; I went to school there. It was particularly hard…for me to keep my mouth shut.” For Basilevsky, there was an even more frustrating problem: The control room was off-limits to him and other scientists taking part in the mission. Relegated to another room in the Crimea complex, they could listen to the crew’s workmen-like dialogue only over a loudspeaker. During mission operations, the researchers were expected to be passive consumers of data, not participants in the exploration. “Scientists were considered, in the beginning, as something unnecessary,” Sasha Basilevsky explains.
Meanwhile, on the Sea of Rains, with its Earthbound masters ever mindful of its safety, Lunokhod made halting progress until, on November 22, having traveled some 646 feet, the rover was put to sleep for the approaching two-week night. During the hibernation, astronomers in Crimea and the French Alps bounced a laser beam off a French-built reflector mounted on the rover; these experiments were designed to provide ultra-accurate measurements of the moon’s periodic wobbles, called librations, as well as the moon’s distance from Earth. Some team members worried about whether Lunokhod could be revived, but after the sun had risen on the Sea of Rains, the rover was ready for its first full lunar day of work.
As the controllers gained more experience, they also gained confidence, until they were able to let the rover proceed as long as they could see no clear hazard on the monitors. Progress had to be halted for three days during the lunar noon, when the lack of shadows made driving too dangerous. Lunokhod logged almost an additional mile before night fell. And during the third workday, starting on January 17, navigators steered the rover back to its landing spot, where the landing stage stood like a tiny fortress.
It was around this time that Basilevsky ventured into the control room at last. “I came and brought a chair with me,” he says. “Nobody allowed me, actually. I just did it. And I stayed. And they looked at me, and nobody said anything. The next day I came with my chair again, feeling ‘I have a right to do this.’ And then, it was my place.”