The Soviet moon-car Lunokhod is now in the Sea of Rains. Statements by a number?
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Background: The Soviet moon-car Lunokhod is now in the Sea of Rains. Statements by a number of Soviet scientists and designers indicate that the self-propelled vehicle has been made with the use of the data on lunar rock and the substances similar to it that are found here on Earth. This could not have been otherwise. The main job of Lunokhod-1 is to move on lunar rock. With time the lunokhod will become a most important means of studying the Moon's rock. It is now relevant to take a closer look at this lunar rock.
It was astronomers who obtained the first data about the properties of lunar rock. They got this information from the specific optical properties of the Moon's surface. Later very important data were supplied through measuring the temperature of the lunar surface. Scientists also measured the properties of the lunar surface in reflecting radar signals and the emanation of radio waves by the Moon itself.
All these data led scientists to believe that the Moon's surface must have a layer of some foamy, porous or mellow grainy substance of Low density. These conclusions were taken as a basis for choosing a ground similar to lunar rock. When a mode of Lunokhod-1 was undergoing checkouts at testing stands and ranges, several kinds of such ground were used. The pictures show two kinds of these stonelike porous and mellow materials.
When the Soviet lunar probe, Luna-10, went to the Moon, it marked a new stage in the Moon's exploration. The studies showed that the Sea of Rains and other lunar seas are made up of basalt clinkers. Their surface was subjected to many strikes by big and small meteorites.
Soviet scientist led by Professor Vinogradov, a member of the Academy of Sciences, believe it is now unquestionable there was a volcanic activity on the Moon. This activity is very close to explosions on impact following strikes by meteorites as far as its effect on the surface and on reducing mountain rock to fragments is concerned. The mellow volcanic deposits on the Earth are closest to lunar rock in all their properties. Another argument in favour of this view is that volcanic areas on the Earth are very similar to moonscapes.
These pictures on the right show some volcanic landscapes. Here are some fields with stones on volcanic ash. These are deposits formed from directed explosions.
On the left we see similar formations photographed by various automatic probes which have made a soft landing on the Moon. This picture shows a helicopter on the stone deposits of a directed explosion. On the left you see the same deposit of stones on the Moon. The black sky shows that the picture was taken on the Moon. Last but not least, here are tracks left by prospectors on the earth ground and here are tracks left by astronauts on the Moon's surface.
This is why we consider volcanic deposits to be the closest substance to lunar rock. Before showing lunar rock I would like to say a few words about the lunar dust theory.
A view prevailed abroad that the lunar surface was covered with a thick layer of light, loose powder, and that a space-ship and astronauts could sink in it. We found a substance an the Earth similar to that kind of dust. It was perlite sand, a mineral substance whose weight is only one fifth of that of water. If you drop a coin into this sand, it will sink in it without trace.
However, this theory has been refuted by the landing of many spacecraft and probes. There are no lunar deposits in the form of dust. Here are samples of volcanic rock. It is a solid basalt and this is pyroclinite, also a solid massive crystal-line rock. This is already a porous rock, volcanic tufa, and this is volcanic slag.
The Soviet lunar probe Luna-16 brought samples of lunar rock back to Earth. Here is a small portion of these samples. It is a mellow, crumbly and grainy substance with a vertical slope.
Now, I am going to show you a model of volcanic ash. It is a substance which has the same properties. If I try to deform it, you will see that it contains a vertical slope. It is mellow and crumbly, and has a certain cohesion. It is very close to lunar rock in its properties. The only exception is that the earth atmosphere changes its properties while on the Moon this cannot happen.
To sum up, I must say that the lunokhod itself is an instrument to assess the properties of lunar rock. The tracks it leaves make it possible to obtain very important data about the mechanical properties and structure of lunar rock. The detailed panoramic views make it possible to obtain a wealth of information about the structure of the Moon's surface. The main value of the lunokhod is that it makes experiments along routes and over a wide area and not on individual spots.
The lunokhod has finished the first stage of the job. Evidently, the data brought by telemetric signals back to Earth will be processed during the lunar night.
Of course, these are just the first steps of the lunokhod, yet these are complex steps. You've probably heard that the mechanical properties of lunar rock are being tested. Scientists are also looking into their chemical composition.
Undoubtedly, the making of a lunar surface vehicle provides scientists into the structure of lunar rock. It is a good vehicle fro drilling, probing, collecting samples and preparing them for a travel to Earth.