The day of March 31, 1966 went down in history forever as another memorable date for Russian cosmonautics. On this day, exactly 50 years ago, the successful launch of the first ever artificial lunar satellite took place. At 13:49:59 Moscow time, a Molniya-M rocket took off from the Baikonur cosmodrome, which brought the automatic interplanetary station Luna-10 to the Moon. The satellite, equipped with various research equipment, successfully entered lunar orbit on April 3, 1966.
The station "Luna-10", the mass of which was 248.5 kilograms, worked in the orbit of the Moon for 56 days. During this time, the satellite managed to complete 460 revolutions around the Moon and carried out 219 radio communications with the Earth. During these communication sessions, Soviet scientists received information about the magnetic and gravitational fields of our planet's natural satellite, the Earth's magnetic shelf, as well as some information about the radioactivity and chemical composition of the lunar surface rocks. On May 30, 1966, the automatic interplanetary station "Luna-10" stopped its work, falling to the surface of the Moon. The planned flight program of the Luna-10 station was carried out in full.
It is worth noting that the Moon, as the closest celestial body to the Earth, has always attracted the eyes of researchers and scientists. Having discovered the way into space, humanity first of all focused on this natural satellite of our planet. At the same time, interest in the moon has not disappeared in the 21st century. Large-scale lunar programs are being worked out today by both Roskosmos and CNSA (China National Space Administration). The priority in the exploration of the Moon remained forever with the USSR. In the Soviet Union, the implementation of their lunar program began almost immediately after the successful launch of the first artificial Earth satellite in October 1957.
In the USSR, a large-scale lunar exploration program was carried out from 1958 to 1976, during these years spacecraft for various purposes were launched to the Moon. Luna is the general name for a series of Soviet automatic interplanetary stations designed to study the Moon and outer space. All launches (in total there were 16 successful and 17 unsuccessful launches) were made from the Baikonur cosmodrome. The program was finally curtailed in 1977 - the 34th launch was canceled; as part of this launch, Lunokhod-3 was to be delivered to the lunar surface.
The Soviet Luna program became a kind of impetus for further exploration of deep space. As part of the implementation of this program, a number of records have been set. For example, on January 2, 1959, the Soviet automatic interplanetary station Luna-1 became the first spacecraft to fly close to the Moon, and the Luna-2 station became the first spacecraft to reach the surface of the Moon, this happened on September 14, 1959 (hard landing). The first soft landing on the lunar surface was carried out on February 3, 1966 by the Luna-9 station, which transmitted images of the lunar surface to the Earth for three days.
Preparation and launch of "Luna-10"
It is worth noting that both the Soviet and American lunar programs were accompanied by a lot of difficulties and haste, which led to accidents. Thus, the flight of the automatic station "Luna-10" was preceded by an emergency launch of a similar station, which Soviet engineers designed and manufactured in record time - in just 25 days. The launch of this station with the help of the Molniya-M launch vehicle took place on March 1, 1966 at 14 hours 03 minutes 49 seconds Moscow time. The three first stages of the rocket ensured the launch of the head unit, which consisted of a spacecraft and an upper stage "L", into the reference orbit of an artificial Earth satellite. But this device did not come out to the Earth-Moon section. In the section of the upper stage "L" operation, there was a loss of stabilization and the automatic station remained in the earth's orbit, it was assigned the index "Kosmos-111". As a result, Luna-10 became its twin station a month later.
This time the rush with the launch was somewhat less, instead of 25 days, all 30 were spent. During the same time, it was possible to analyze the reasons for the failure of the first launch. It was possible to establish and promptly eliminate some weak points in the design of the upper stage "L". As a result, on March 31, 1966, at 13:46 and 59 seconds, another Molniya-M rocket was launched from the Baikonur cosmodrome, on top of the three stages of which the upper stage "L" and the space station "Luna-10" were located. Structurally, this station was similar to the station "Luna-9", but instead of an automatic lunar station, a detachable sealed container was placed on the "ten", which was also an artificial satellite of the Moon (ISL). Since Luna-10 did not need equipment and an engine to make a soft landing on the Moon, the workload of the station was increased by almost 3 times compared to the “nine”. The total mass of these spacecraft was the same - about 1584 kilograms, but the mass of the stations was different - 248.5 kilograms for Luna-10 versus only 100 kilograms for Luna-9.
The day after launch, on April 1, after receiving a command from the Earth, the Luna-10 interplanetary station corrected its orbit and moved towards the intended target. Two days later, on April 3, on the approach to the natural satellite of our planet, a braking propulsion system was launched for 57 seconds, after which the station successfully entered a circumlunar orbit with a minimum altitude of 350 kilometers and a maximum altitude of 1016 kilometers. In this orbit, Luna-10 made a complete revolution around the Moon in 2 hours 58 minutes 11 seconds. On April 3, at 21 hours 45 minutes 39 seconds, a sealed container crowning it separated from the main block of the station, which became the ISL. This first ever artificial satellite of the Moon made 450 orbits around it, having spent 56 days in lunar orbit.
Design and composition of equipment "Luna-10"
To launch the Luna-10 interplanetary station, a four-stage medium-class launch vehicle Molniya-M was used, which is part of the R-7 launch vehicle family. As the fourth stage, it used the "L" block, which was the first rocket block in the Soviet Union that had the ability to launch in zero gravity. The launch mass of the rocket was 305 tons, the length was more than 43 meters, and the diameter was more than 10 meters. Later, the Molniya-M launch vehicle became the main vehicle for the creation of three-stage versions of the Voskhod and Soyuz missiles. It was successfully operated for almost half a century (the last launch was carried out on September 30, 2010 from the Plesetsk cosmodrome), after which it was replaced by a more modern Soyuz-2 rocket with the Fregat upper stage.
Prelaunch preparation of the Molniya carrier rocket
The spacecraft "Luna-10" was originally developed to enter orbit an artificial satellite of the Moon and conduct research both on the Moon itself and in the circumlunar space. At the same time, the ISL was made quite simple in design and composition of the equipment installed on board. There was no orientation system on the artificial satellite, so this unit made a non-orientable flight. At the same time, the ILS inner sealed container contained: telemetry equipment intended for collecting and transmitting scientific and service information to Earth; VHF radio system and UHF transponder RKT1; software-timed device; electronic components of scientific instruments, as well as chemical current sources. A fan was included in the thermoregulation system of the sealed container of the artificial satellite; excess heat was discharged directly through the walls of the container. On the outer side of the satellite, a magnetometer rod (1.5 meters long), antennas of radio complexes and sensors of scientific instruments on board were installed. Outwardly, the first artificial satellite of the Moon looked like a small cylinder, which was crowned with an unevenly set cone with a rounded top.
The Luna-10 scientific equipment included: a gamma spectrometer designed to study the intensity and spectral composition of gamma radiation from the lunar surface, which characterizes the type of lunar rocks; a device for studying solar plasma - D-153; the SL-1 radiometer, designed to study the radiation situation near the Earth satellite; three-component magnetometer SG-59M on a rod 1.5 meters long, designed to study the interplanetary magnetic field and refine the lower limit of the possible magnetic field of the Earth satellite; meteorite particle recorder - RMCH-1; a device for detecting X-ray fluorescent radiation of the Moon - RFL-1; ID-1 is a device designed to register infrared radiation of the lunar surface, as well as to clarify data on its thermal regime.
Achievements of "Luna-10"
As noted above, the first ever artificial lunar satellite spent 56 days in orbit, performing 219 radio communications with the Earth. During this time, according to experts, it was possible to fully implement the planned flight program, having received a huge amount of important and very interesting information about the natural satellite of our planet. In particular, it was possible to establish: that the magnetic field of the Moon has, most likely, a solar origin; that in the orbit of the Moon the density of meteors is higher than in interplanetary space; that the disturbance of its motion due to the noncentrality of the gravitational field is 5-6 times higher than the disturbance caused by the gravitational influences of the Sun and the Earth.
Using the method of gamma spectrometry, it was possible for the first time to measure the content of natural radioactive elements (U, Th, K) and to determine the type of rocks that lie on the lunar surface. The presence of unoxidized forms of iron, silicon and titanium on the surface of particles of regolith (surface layer of loose lunar soil) was also found. In addition, with the help of "Luna-10" for the first time it was possible to obtain data on the general chemical composition of the Moon by the nature of the gamma radiation of the lunar surface. It turned out that the overall level of this radiation is slightly higher than the level of gamma radiation over the rocks of the earth's crust. Also, the work of the ISL allowed Soviet scientists to conclude that the moon does not have radiation belts.
The flight of the Luna-10 station was another achievement of the Soviet Union in the space race, becoming another confirmation that the country is capable of unique space achievements. Based on the results of the Luna-10 flight, the FAI (International Aviation Federation) officially registered the priority scientific and technical achievements of the Soviet station:
- launching an artificial moon satellite into orbit;
- for the first time in the world, carried out scientific and technical research and measurements using an automatic station, which was launched into the orbit of the moon.
An interesting fact: during the 23rd Congress of the CPSU, the melody of the "Internationale" was transmitted from the artificial satellite "Luna-10" (from 1922 to 1944.the official anthem of the USSR, later the official anthem of the CPSU), which the delegates to the party congress listened to while standing, greeted with applause.