From the late 1950s until about the mid-1970s, the USSR carried out a program of studying the Moon through automatic interplanetary stations. As part of one of the stages of this long-term program, remotely controlled mobile research probes of the E-8 series worked on the surface of the Earth satellite for several months in 1970-71, as well as in 1973. The whole world knows them as Soviet moon rovers.
Stages of the lunar program of the USSR
The devices used to study the Moon and surrounding space are usually divided into three generations. Automatic stations belonging to the first generation had the task of achieving the delivery of the probe to the Earth's satellite, as well as flying around it and photographing the reverse side with the transmission of images to Earth. The devices of the second generation were designed for a soft landing, and, in addition, for launching an artificial satellite into a lunar orbit, photographing the surface of the Moon from its board and working outcommunication systems with the Earth.
The third generation of stations (E-8 series) was created for a deeper study of our nearest space neighbor. Within its framework, mobile devices controlled from the Earth were designed - lunar rovers, as well as a heavy moon satellite E-8 LS and stations E-8-5 with a return vehicle designed to deliver soil from the Earth satellite.
Series of interplanetary stations E-8
Since 1960, OKB-1 (now Energia Corporation) has been considering the creation of a self-propelled lunar vehicle. In 1965, work on the design of interplanetary stations was entrusted to the design bureau of the Machine-Building Plant (since 1971 - NPO) named after. Lavochkin, led by G. N. Babakin, who in 1967 prepared documentation on their own version of the device. In particular, the design of the chassis has been completely changed. Instead of the previously envisaged caterpillars, the designers equipped the Soviet lunar rovers with eight drive wheels 200 mm wide and 510 mm in diameter each.
The station of the E-8 series consisted of two modules: the KT landing rocket stage and, in fact, the 8EL lunar rover. Delivery to the Moon was to be carried out by a Proton-K launch vehicle equipped with an upper stage D.
Design and equipment of the moving probe
The rover is a sealed container. This is an instrument compartment mounted on a self-propelled wheeled chassis. The lid of the container is equipped with 180 W solar cells for recharging the buffer battery. ChassisIt has a set of sensors, with the help of which the properties of the soil, the permeability were assessed and the distance traveled was recorded. This purpose was also served by the lowered ninth wheel, rolling freely and not experiencing slippage.
Instrumental content included radio complex equipment, remote control automation units, power supply and thermoregulation systems, television systems and scientific instruments: spectrometer, X-ray telescope, radiometric equipment.
Soviet lunar rovers were equipped with two navigation cameras in the front of the hull and four panoramic telephoto cameras.
Main device tasks
E-8 series devices were designed to solve such applied problems as:
- working out the remote control of the mobile probe;
- study of the lunar surface in terms of its suitability for moving automatic vehicles;
- testing and development of the basic transport system for the Moon;
- study of the radiation situation on the way to the Earth's satellite and on its surface;
- in the future - survey of the main and reserve areas for the landing of a manned spacecraft and support for the expedition at some stages, in particular, during landing or in the event of an emergency on the Moon.
Was the Soviet lunar rover fit to serve as a vehicle for an astronaut? As part of the manned expedition program, it was planned to create such a machine. However, due to the closure of the projectit was not implemented.
Lunokhods carried out a scientific program to study the chemical composition and physical characteristics of the soil, as well as to study the distribution and intensity of X-rays from various space sources. For laser location from the Earth, a corner reflector created in France was installed on board the vehicles.
Machine control
The system providing control of the lunar rovers included the following elements:
- complex of equipment on board the unit itself;
- ground complex NIP-10, located in the Crimea, in the village of Shkolnoye, where space communications equipment and a unit control center with control panels for crew members and a room for operational telemetry processing were located.
In the same place, near Simferopol, a lunodrome was built - a training ground for crew training, arranged taking into account data received from Luna-9 and Luna-13.
Two crews were formed, each with five people: commander, navigator, driver, flight engineer and operator of a highly directional antenna. The eleventh member of the control group was the backup driver and operator.
Not a single Soviet lunar rover has ever been on the far side of the Moon due to the difficulties associated with the organization of communications and control. Also, the landing of manned ships was planned only on the visible side.
Lunokhod-0
In total, four self-propelled lunar vehicles were built. The very first of them did not reach the goal, because at the launch on February 19In 1969, a launch vehicle crash occurred, ending in an explosion at 53 seconds of flight.
The device lost in the accident received the code name "Lunokhod-0".
Lunokhod-1
The next probe of this type was launched as part of the Luna-17 station on November 10, 1970. On November 17, she landed in the western region of the Sea of Rains. The first Soviet lunar rover started its work on the Moon after leaving the landing platform of the station.
The weight of the machine was 756 kg, the dimensions were 4.42 m long (with the solar panel open), 2.15 m wide and 1.92 m high. When moving, it left a track 1.60 m wide. Moving along the surface of the satellite was carried out for 11 lunar days. With the onset of the moonlit night, the cover of the case was closed, and the device waited for the onset of the day in a stationary state.
A few words about what the first Soviet lunar rover discovered on the Moon and what results it achieved. He worked three times longer than planned - until September 14, 1971, examined an area of 80 thousand m 2 and walked a total of 10.54 km. More than 20 thousand television pictures and over 200 panoramas of the Moon were transmitted to Earth. Physical and mechanical tests of the soil were carried out more than 500 times, and its chemical composition was studied at 25 points. Laser location using a corner reflector, performed by Soviet and French scientists, made it possible to determine the distance to the Earth's satellite with an accuracy of 3 meters.
Lunokhod-2
Launching the next station of the E-8 series("Luna-21") took place on January 8, 1973. The craft landed safely in the Sea of Clarity on 16 January. There were no fundamental differences from the previous Lunokhod-2 probe, but some improvements were made to its design, taking into account the wishes of the driver-operators.
In particular, a third navigation camera was installed on it at the height of human growth, which greatly facilitated the control of the machine. Some changes also affected the instrument composition, and the mass of the device was already 836 kg.
Photos from the Soviet lunar rover number two have already been received in the amount of more than 80 thousand. In addition, he broadcast 86 television panoramas. In conditions of a rather difficult terrain, the self-propelled probe functioned for 5 lunar days (4 months), covered 39.1 km, studied in detail the soil and rock outcrops of the Moon. The distance to our natural satellite this time was already determined with an accuracy of 40 cm.
On the question of finding moon rovers
In 2010, both the first Soviet lunar rover and the second were discovered in images taken by the American Lunar Orbital Probe LRO. In connection with these events, information was spread about allegedly "lost" by Soviet scientists, and now "found" devices. Specialists who worked in the lunar program of the USSR emphasize that the vehicles were never lost. Their coordinates were known with an accuracy achievable for that time. Lunokhod 1 was photographed by the crew of Apollo 15 from low orbit, and the landing site of Luna 21 was photographed by the astronauts of Apollo 17, moreoverthese images were used to navigate the second vehicle.
As for the photographs taken by the LRO station, due to their high resolution (0.5 meters per pixel), they played a significant role in clarifying the coordinates of those places where the Soviet moon rovers remained forever, stopping their work. This clarification is also important because in 2005, in connection with the creation of a new unified selenodetic network, the coordinate binding of the details of the surface of the Earth's satellite was updated.
Lunokhod-3
In 1977, the next self-propelled probe was supposed to go to the moon. It featured major improvements to the navigation system. However, the third Soviet lunar rover, designed in 1975, fully equipped and tested, never went to the Moon. In the lunar race, as in other space programs, the initial priority was given to political and economic, rather than purely scientific motives. By the way, real scientific and technological development is generally inseparable from the economy.
After 1972, the US effectively closed its program. The last Soviet station, Luna-24, visited the Earth's satellite in 1976, delivering soil samples from it. What happened to the last machine? "Lunokhod-3" took a place among the exhibits of the NPO Museum. Lavochkin, where he remains to this day.
The role of lunar rovers in the development of astronautics
Designed by Soviet scientists and engineers, the first ever mobile probes controlled from the Earth were a huge contribution to technologycreation of automatic interplanetary stations. They demonstrated the great potential and prospects of planetary rovers in exploration, and in the future, perhaps, in the exploration of other planets.
Soviet lunar rovers proved the suitability of such machines for long-term operation, the ability to comprehensively study fairly large areas, unlike stationary vehicles. Now self-propelled probes are certainly a necessary tool for planetary science. It should be remembered that "lunar tractors" are the ancestors of today's high-tech units equipped with on-board computers and modern automatic equipment, as well as machines that have yet to leave tracks on the surface of other planets.
