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Forgotten Soviet Moon Rover Beams Light Back to Earth (ieee.org)
160 points by jcr on May 27, 2011 | hide | past | web | favorite | 32 comments

I love the look of that Lunokhod rover.

It reminds me of Russian author Victor Pelevin's wonderful satirical mini-novel "Omon Ra". The Soviet moon missions carried a heavy secret...

There's a free English translation of Omon Ra available online:


I don't know about the quality of this translation, but I'd absolutely recommend the book to anyone who's interested in post-Soviet Russia... And can stomach Pelevin's sprawling irony, which may be the only appropriate literary tool for approaching contemporary Russia :)

The Lunokhod rovers have an unusual and unique appearance because they used pressure vessels to contain the electronics.

Holy pressure vessel batman! I did not know that and find it weird and fascinating.

Am I the only one who thinks it looks like a high-tech baby stroller?

I really liked the look of it as well, but the thing that got me thinking is how similar the wheels/suspension were to the NASA Opportunity and Spirit rovers.

Thinking what?

A bit rough but still a fair question.

Obviously, the first thing I was thinking about was the similarity of the two wheel/suspensions designs. Next up, I was wondering about the engineering decisions which resulted in the designs being similar. The main question I have is, "What advantages did the multi-wheel designs have?" I think it must have something to do with trade-offs between mobility on the (theoretical) terrain and power consumption, but really, I'm just guessing. Whatever the reasons are for the similarities, learning the engineering and testing behind the two designs would be fascinating.

If I remember correctly, in this documentary "Tank on the Moon"[1], they said, one of the scientists who worked on the Lunokhod missions consulted with NASA for part of the design of the Mars rover around 1995. Apparently he worked on the wheel design, to help overcome grip and other factors on the Mars terrain. [1] http://science.discovery.com/tv/tank/tank.html

The US rovers have used a rocker-bogie[1] system for their suspension. While the wheels look similar, the suspension on the Lunokhod almost looks like leaf springs.

[1] http://en.wikipedia.org/wiki/Rocker-bogie

nah. Here's a detail of Lunokhod 3 wheels: http://upload.wikimedia.org/wikipedia/commons/8/8c/Lunokhod_...

Given the time of these designs, one cannot rule out that it is more correct to say that there were 1.5 designs, not 2. Both parties involved tended to keep a close look on the competition.

Slighty deceptive headline. At first I thought it sounded like thus ancient robot was transmitting light to earth.

Not so. It merely has a reflector that bounces earthbound researcher-gnereated laser photons back.

Apparently Lunokhod 2 is now privately owned by a certain "Lord British":


> For every 1018 photons shot at the moon, only a single photon returns to the telescope.

Is that really 1018, or did 10^18 get mangled on its way onto the web?

The latter. There's no way that it's reflecting a million watts back to the Earth's surface (1/1018 of the main beam power). Or to put it another way, with a beam "footprint" of 2km across, and with the size of the rover rather less than 100 m across, there's no way it alone could return that high a percentage of the light sent to it.

This is such an interesting story. This guy has quite the gravity labratory.

I like the analog rover, even if it doesn't run Python. What a difference 30 years makes.

Wow, without parachutes, how did they land that thing?

Looks like a ancient ancestor of Spirit/Opportunity.

> Wow, without parachutes, how did they land that thing?

Erm... parachutes work through friction generating air resistance. There is no air on the moon so parachutes don't do anything. They'd be pointless encumbrance.

Much like apollo, the Luna landers used retrorockets (or tried to, anyway, all attempts resulted in surface crashes until Luna 16)

> Looks like a ancient ancestor of Spirit/Opportunity.

Pretty much, and prefiguring Spirit/Opportunity Lunokhod 1's mission was intended to last 3 lunar days (a bit under 3 earth months) and went through 11 instead (the mission clocked in at 322 earth days)

Your comment incorrectly states that Luna 1 to Luna 15 crashed into the Moon. Luna 16 was not the first to successfully soft land and not all crashes were accidents. Only 6 of the 14 Luna missions intended to soft-land on the moon actually crashed. (There were a lot more Luna missions in total, some were not supposed to try soft-landing, and some failed to even reach Moon orbit.)

For those who are interested in Space trivia:

According to Wikipedia[0], Luna 2 intentionally crasheded into the Moon, making it the first human-made object to land on it. Luna 5, 7, 8 failed to soft-land, making Luna 9 the first object to soft-land on the Moon. Luna 10, 11, 12 and 14 were designed to orbit the Moon and crash into it after they failed. Luna 13 successfully landed on the Moon.

Luna 15 was supposed to bring back soil samples, but it crashed into the Moon as well. (More space race trivia: It was supposed to bring back lunar soil samples before Apollo 11 returned to Earth. Armstrong and Aldrin were on the surface of the Moon when Luna 15 impacted.)

Luna 16 was the first unmanned probe to successfully land on the Moon and return a soil sample (which is an event even rarer than manned moon landings).

Luna 17, which carried the Lunokhod 1 roboter mentioned in the artcile landed successfully as well.

Luna 18 (another planned soil return) crashed, Luna 19 successfully orbited the Moon for a year and later crashed into the Moon.

Luna 21 also soft-landed carrying Lunokhod 2, the second roboter mentioned in the article.

Luna 22 and Luna 23 were also soil return probes, but Luna 22 crashed and Luna 23 damaged the return probe on landing (the landing was a soft-landing though).

Luna 20 and 24 both successfully landed on the Moon and returned to Earth with soil samples, making Luna 24 the last man-made object to return from the Moon to Earh.

0: http://en.wikipedia.org/wiki/List_of_man-made_objects_on_the...

> Your comment incorrectly states that Luna 1-15 crashed into the moon.

Not exactly. It incorrectly states that all luna landers (therefore landing attempts) resulted in crashes, not that all luna missions preceding 16 were or contained landers.

Thank you for the correction on 9 and 13, though, I had forgotten about them.

My bad, I misread your comment as "It took 15 tries to land on the moon".

Fair enough. No harm done.

"return a soil sample (which is an event even rarer than manned moon landings)"

Assuming that rarer isn't the right word, mind clarifying the point you were making? (Genuinely interested rather than being pedantic.)

Event A: Manned Moon landing

Event B: Unmanned probe landing on the moon and returing soil samples

Event A is rare and happened 6 times (Apollo 11, 12, 14, 15, 16, 17), event B happened 3 times. Thus event B is even rarer(?) than event A.

I am not a native speaker, can you please tell me the correct word to use in place of "rarer"?

I'm sorry, your English was fine, my brain just wasn't turned on and I misread what you wrote, and indeed what I quoted you as saying. Apologies!

That's what I meant about "without parachutes" - that they couldn't use them without atmosphere.

They used airbags.

You are probably thinking of the Mars Exploration Rover Mission (Spirit and Opportunity) landings on Mars. While airbags were deployed to protect both Spirit and Opportunity during landing, descent speed was managed by supersonic parachute and retrorockets.

The Luna 9 probe, which achieved the first-ever soft-landing on the moon, used air bags.


Use of such is not incompatible with the use of retrorockets.

Thank you for the link regarding Luna 9; I did not know that.

You originally said, "Use of such is not incompatible with the use of retrorockets. As a matter of fact, the latter are used first."

Just to provide clarity, I was referring to the EDL (Entry, Descent, Landing) profile of Spirit and Opportunity. Their EDL profiles first deploy the airbags, then fire the retrorockets.


Step 12: Airbags inflate Step 13: Retrorockets fire

Or even the Mars Pathfinder mission.

Nope, thrusters, much like the Apollo landers.

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