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Mashable.com's Every rover, ranked by distance traveled on the moon and Mars; The 13 rovers, ranked. calls attention to this amazing feat, and a review of basic statistics and discussions on odometry are available.

Driving this far requires careful navigation, avoiding crashing into things, getting hung up, stuck in "sand traps" or falling into holes. You need a good safe stretch of luna firma and some luck, but also plenty of data and careful attention and risk management.

You've also got to have every critical bit survive the cold lunar nights and be able to soak up and use plenty of solar power during the day to drive those 1970's motors and wheels across rough terrain. Certainly the low lunar gravity helped here.

And the four months is really two months because of the lunar night.

Question: How (the heck) did Lunokhod 2 drive, navigate and survive a ~40 kilometer drive over four months on the Moon using 1970's technology?

All Mars and lunar rovers ranked by how far they've driven. Credit: Bob Al-Greene / Mashable

All Mars and lunar rovers ranked by how far they've driven. Credit: Bob Al-Greene / Mashable

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    $\begingroup$ What sort of answer are you looking for here? As written, the question is very broad. $\endgroup$ Aug 16 at 3:07
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    $\begingroup$ Possibly the main reason Lunokhod could range so fast is because of the signal delay between the earth and the moon, which is a 2.6 second round trip. Growing up playing quake in the 90's in new zealand, I can confirm that this feedback delay, while unplayable normally, is still sufficient to move around relatively easily. Mars has a signal round trip of between 8 and 48 minutes. Navigation therefore proceeds at a crawling pace. $\endgroup$
    – Ingolifs
    Aug 16 at 4:30
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    $\begingroup$ Maybe the Soviet Union had excellent engineers? $\endgroup$
    – Patrick
    Aug 16 at 12:10
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    $\begingroup$ @dlchambers Yes, sure, the country that sent the first satellite and the first person to space did so using stone age tools. It is true that in some areas the Soviet Union was behind the west (microelectronics), but in others it was ahead (metallurgy). If you believe the Soviet Union had the technological level of 1850's Russia you're mistaken. $\endgroup$
    – Patrick
    Aug 16 at 13:50
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    $\begingroup$ I think the real question that is bothering you is "why is nobody repeating the feat". And the answer is same as always: we (the humanity) are not doing it not because we can't but because nobody is willing to pay for it anymore. $\endgroup$
    – Agent_L
    Aug 16 at 18:09
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A few interesting videos about the lunokhod rovers:

The chief designer of the lunokhods (Lunokhod 1 & 2) was Aleksandr Kemurdzhian, a tank designer. Being a tank designer his initial designs had the lunokhod use tracks, but research indicated tracks could get stuck in certain situations so the design was changed to eight independently moving wheels. According to Secret Soviet Lunar Rovers and Extra Terrestrial Cars - Lunokhod, the vehicles could move if only three wheels weren't stuck. The development of the lunokhods was very well tested and researched prior to construction and deployment.

To power the craft during the lunar day solar cells on the inside of a lid for the craft were used. During the lunar night, the lid was closed, the internal compartment of the lunokhods was filled with a gas heated by an external polonium-210 source.

The lunokhods had four corner cameras produced high-resolution panoramic images, with a pair of front-mounted TV cameras for the rover’s operators.

Each lunokhod was controlled by a five man team, a driver, commander, navigator, engineer and radio operator – having practiced on a simulated lunar surface.

The sweating driver was guided not by video but a succession of still images, updated every 20 seconds. He had to contend with the 2.5-second signal delay, as well as a metre-wide blind spot ahead. Lunokhod 1 had two speeds: 0.8 km/h or 2km/h, plus reverse gear. Drivers recalled details from previous images to manoeuvre safely and were dependent on shadows to make out surface relief. They did not drive during the three days of lunar noon, or when the Sun was low in the sky. Each lunar night they left the rover to hibernate.

From ROBOTIC AND MANNED LUNAR ROVERS OF THE XX CENTURY: THE VIEW FROM THE XXI CENTURY

The accumulated experience of the crew resulted in an increased duration of typical non-stop driving time from 50 s for Lunokhod-1 to 350 s for Lunokhod-2.

The remote control drivers were located at Simferopol in Crimea.

The design of the lunokhods was robust enough for even longer missions but the demise of Lunokhod 1 was the exhaustion of polonium-210. Lunokhod 2 failed due to overheating after it was accidentally driven into a crater the drivers didn't notice. Lunokhod 2 was simply driven through the crater which, unknowingly, had soft walls which covered part of Lunokhod 2 with dust. When then lid was open the dust was deposited on thermal exchange unit and Lunokhod 2 stopped functioning shortly afterwards.

As a side note, Aleksandr Kemurdzhian designed rovers for the clean up of Chernobyl, after the ones obtained from the then East Germany failed to operate as anticipated.

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    $\begingroup$ Lunokhod 1 has a big problem - always switched on brackes. And problem with pensil-beam antenna. $\endgroup$
    – A. Rumlin
    Aug 16 at 18:54
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    $\begingroup$ "Each lunokhod was controlled by a five man team, a driver, commander, navigator, engineer and radio operator". What about the shooter? ;-) $\endgroup$
    – Edheldil
    Aug 17 at 12:21
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    $\begingroup$ The gunner got out and pushed! The loader was automatic so he was looking for another job. $\endgroup$ Aug 17 at 13:04
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    $\begingroup$ @Edheldil In reality, the Lunokhod movement was operated by a team of about 100 specialists. $\endgroup$
    – A. Rumlin
    Aug 17 at 17:32

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