From cautious crawls to wild rides—exploring the Moon on wheels.
They’re the vehicles with the biggest parking spaces in the universe and the most gorgeous view of Earth. Six of them are currently located 384,400 km from us—on the Moon. They are all testimony to humankind’s thirst for knowledge and quest for adventure:
Three US-built Lunar Roving Vehicles (LRVs) from the 1970s, in which six astronauts drove a total of over 90 km on the Moon’s surface; two Soviet-launched, eight-wheeled Lunokhod vehicles that were controlled remotely from Earth; and finally Yutu, the Chinese lunar rover which has been on the Moon since 2013. Soon these vehicles are due for a visit from an Audi when we launch the Audi Lunar quattro.
The first vehicle on the Moon
To this day, it is still overshadowed by the Americans’ accomplishments, even though its work was pioneering: the mobile Moon robot Lunokhod (“Moon walker”).
How do you steer a radio-controlled vehicle where the signals need to cover an overall distance of 768,000 km? This question was answered by the Soviet Union in 1970 with an impressive performance. While Lunokhod might look like a souped-up tub, it was in fact the first vehicle to explore the Moon. The “Moon walker” was maneuvered by a five-member team on Earth, but soon after it landed, they discovered a design flaw: the cameras used for its navigation were set too low—so Lunokhod was short-sighted.
This meant the rover kept getting stuck in lunar craters. But, thanks to its eight wheels equipped with crampon-like ridges, the Soviets managed to get it out again each time. Lunokhod was a success: instead of its hoped-for 90 days of service life, the rover stayed in operation for 11 months and drove 10.5 km across the Moon’s surface. Its last position within a range of several km was unknown for years. Just recently, in March 2010, Lunokhod 1 and its transporter, Luna 17, were discovered in new images taken by a NASA lunar orbiter.
Cruising through Hadley Rille with 0.25 horsepower and country music
No roads, no rules, no traffic: David Scott and Jim Irwin’s first trip in their Moon rover—on the ultimate off-road terrain.
“This is really a rock ’n’ roll ride,” David Scott radioed to Houston. “I’m getting seasick.” The sortie broadcast on US television on July 30, 1971 was certainly a wild one. Bouncing along to a soundtrack of country music, all four of the lunar rover’s wheels sometimes left the ground. Luckily, its route through the Hadley Rille gorge contained few boulders that might have posed a danger—“and no oncoming traffic,” as the astronauts radioed back to Houston. And that was a lucky thing, because they encountered a problem: the seat belts were too short.
The engineers on Earth hadn’t considered the fact that the Moon’s reduced gravity would prevent the space suits from compressing very far. When they sat down, the astronauts were simply too fat for the seat belts. Buckling up took three minutes—which is a lot of valuable time on a Moon mission.
Without their Moon buggy, though, they would only have been able to accomplish a fraction of their tasks, because walking on the Moon’s treacherously crater- and chasm-riddled surface is slow going. “This is a super way to travel. It’s easy to drive. No problem at all,” Commander Scott reported after the first tour through terrain that truly deserves to be called off-road.
A new mission—a new car
Apollo 16 transported the second Lunar Roving Vehicle into space. The astronauts drove it 27.1 km on the Moon—and picked up “Big Muley.”
Big Muley is the nickname for Lunar Sample 61016. Weighing in at 11.7 kg, it is the largest and heaviest rock ever brought back to Earth by the Apollo program. During the first of three explorations of the Descartes Highlands, Bill Muehlberger, the field geology team leader, ordered astronaut Charlie Duke to pick up a big rock he had seen in the camera’s live images.
There was one problem: the rock lay next to a crater ten meters deep. “If I fall into Plum Crater getting this rock, Muehlberger has had it!” grumbled Duke, who drove over 4.2 km for the mission and took over seven hours to heave the rock into the rover. Today, Big Muley is on display at the Lyndon B. Johnson Space Center in Houston, Texas. Incidentally: after Apollo 15 and Scott and Irwin’s seat belt malfunction, the belts were tested starting with Apollo 16—and their length was adjusted as needed.
Tape holds even at high speed
The last human exploration of the Moon’s surface called for extra creativity on the part of the astronauts.
Lunar maps, duct tape and a couple of clamps borrowed from inside the lunar module were the tools the astronauts used for the impromptu repair of the rear fender, which had broken, leaving the drivers covered with Moon dust and unable to see properly. Still, unlike its predecessors, the Apollo 17 LRV evidenced no steering flaws. While the LRV on the Apollo 15 mission averaged just eight km per hour, Eugene Cernan, Commander of Apollo 17, set the lunar land-speed record of just under 18 km per hour in the wildly bouncing Moon buggy. On December 14, 1972, Cernan became the last person to date to leave the Moon’s surface. He left his daughter’s initials, TDC, in the dust, declaring: “We leave as we came and, God willing, as we shall return, with peace and hope for all mankind.” Eugene Cernan and Harrison Schmitt’s stay of three days and three hours marked the longest of the Apollo missions. The third Lunar Roving Vehicle has been parked on the Moon ever since – and we’re keen to get a closer look at how it survived.
The second “Moon walker” sets records
At least 39 km driven on the Moon: Lunokhod 2, the next-generation “Moon walker,” truly went the distance.
At 840 kg, Lunokhod 2 is the all-time heavyweight among the lunar rovers. But despite its bulk, the vehicle, which was remotely operated like its predecessor, turned out to be a top performer. Up until 2013, it was estimated to have gone 37 km, but in fact this figure, indicated by the wheel rotations, was too low. It is thought to have travelled at least 39 km.
The new measurement of its tracks, which are still visible, yielded the higher number. Lunokhod 2 held the record for off-Earth roving until very recently, when the Mars robot Opportunity topped it on July 27, 2014. Lunokhod 2 landed on the Moon on board Luna 21 on January 15, 1973, near the Le Monnier crater, and roamed the surface between January 18 and May 3. Lunar dust that had collected on its solar cells prevented them from collecting enough energy for continued operation.
But before that happened, it had gathered 86 panoramic images and some 80,000 TV images and transmitted them to Earth along with other data. Even today, lasers can still measure the exact distance from Earth to Lunokhod 2. It was not until 2010 that tracks of the rover were recorded by a NASA orbiter. This was especially good news for Richard Garriott, an entrepreneur who bought Lunokhod 2 in December 1993 at an auction in New York for $68,500. That makes Garriott the only person who can claim private ownership of an object on a foreign celestial body.
The third nation to conquer the Moon sends the Jade Rabbit
It was not until the new millennium that another rover landed on the Moon: on December 14, 2013, the Chinese Chang’e-3 spacecraft placed the Yutu “Jade Rabbit” rover on the Moon.
Jade Rabbit, or Yutu, is an unmanned, remotely operated rover. The name, after the rabbit that is a pet of the Moon goddess in Chinese mythology, was selected in an online poll, with 649,956 votes. Tipping the scales at 140 kg, the Jade Rabbit was a lot less hefty than the Soviets’ remote-controlled rovers from the 1970s—Light vehicles are cheaper to transport—but it was still light-years behind today’s lightweight construction technology.
Its technical equipment is also far more advanced than that of the US rovers, which were designed chiefly for passenger transportation. Yutu was designed to spend three months exploring the Moon’s surface and performing activities such as searching for natural resources with radar. But, after just over a month and a mere 114 m, Yutu got stuck. Researchers on Earth still occasionally pick up its signals. However, China is already working on ambitious new plans: the first sample return mission is scheduled for 2017; Yutu’s twin is slated to land on the far side of the Moon by 2020; and a crewed mission by 2035 is even in the works.
Pointing the way into the future
Light, efficient, featuring quattro drive: optimized with Audi technology, the PTScientists rovers represents the future of lunar exploration.
Light, efficient, featuring quattro drive: optimized with Audi technology, the PTScientists rovers, represents future of lunar exploration.
The Audi lunar quattro is the Moon-mobile designed by, PTScientists, the private team of space engineers based in Germany who are racing to be the first privately-funded mission to the Moon. Designed by PTScientists head of development Jürgen Brandner, the rover has been tested and optimized by Audi engineers in drive, lightweight construction, power supply and other areas.
The Audi Lunar quattro has a mass of just over one-thirtieth as much as a Lunokhod rover, will feature drive mechanisms no other lunar vehicle has, and, thanks to its highly efficient ultra battery, will boast a range enabling entirely new scientific experiments.
So why still all the secrecy? Because all the developing, testing, changing, scrapping and redesigning is still going on. Day after day, week after week. To make it even lighter, even more stable, even more efficient—because on the Moon, after all, reliability and sustainability are even more mission-critical than for Earthbound vehicles. The Audi Lunar quattro is slated to be transported to the Moon on a Falcon 9 rocket by SpaceX and lowered to the surface near the Apollo 17 landing site in late 2018. And who knows: maybe the first Audi on the Moon will run across the US rover that’s been waiting for a visit since 1972.