First part of the review: Venus - Russian spaceships launched to the planet in 1961-1975. In this section Haim Mazar reviews the launches carried out in the sixties
Sputnik 7
On February 4, 1961, the USSR launched the Sputnik 7 spacecraft into Earth orbit. The purpose of the launch was to land a spacecraft on the planet Venus. The launch was supposed to come from Sputnik 7. That means two spaceships were launched side by side. A mother spacecraft that orbits the Earth and from which a spacecraft that is supposed to reach Venus was detached. The Russians said that the purpose of the test was to complete a powerful launch system that would allow the launch of heavy spacecraft for various purposes.
Sputnik 7 was launched into an elliptical orbit that is 203-302 km from the ground. The entire lap lasts 89.8 minutes and the angle of inclination is 65 degrees. The spacecraft was launched from a multi-stage launcher and weighed 6483 kg. It was equipped with various measuring devices. A special control system was built to monitor the movement of the spacecraft.
Two Italian radio amateurs said they heard a human voice that they thought came from the spaceship. They picked up "a transmission of metallic signals in which sounds similar to a strange human voice were combined". The sounds of human breathing and pulse sounds can be distinguished. The observatory in West Germany's Bochum picked up sentences in Russian. On February 7, the spaceship changed its flight path and broadcast waves several times "as if it were trying to mislead those following it". On February 26, the spacecraft entered the atmosphere and burned up. If these reports from Russian foreign sources are true, then on the face of it it looks as if the Russians were trying to hide something. The way to check this is to open the archives of the Russian space agency and see what was really there. It is hard to believe that the Russians would allow this.
More of the topic in Hayadan:
- Venus for the advanced - part XNUMX of the review about the Soviet spacecraft that explored Venus - the seventies
- A review of the Soviet Union and Russia's space program
Venera 1
The first in the series of "Venara" spacecraft (in the West these spacecraft were known as Venus), was the Venera 1 spacecraft. The spacecraft was launched on February 12, 1961 to make a flyby of Venus. Although the spacecraft passed within 100,000 km of it, the mission failed, because contact with it was lost on February 27 when it was 7.56 km from Earth. Several attempts were made to renew the connection with the help of the Jedrell Bank Observatory in England but without success. The spacecraft was supposed to reach its destination between May 19 and 20, this year.
The diameter of the spacecraft is 1.13 meters, its height is two meters and it weighs 644 kg. The spacecraft is built in two parts. One part contains the engines, flight aids and instruments for interstellar research. In the second part are the special instruments for investigating the planet. The spacecraft's transmitters are powered by chemical batteries and solar collectors. The temperature in the spacecraft is 20 degrees and the pressure is constant. Contact with you was once every five days.
The launch is done in two stages:
- A. The launch of the satellite Sputnik 8. This vehicle weighs 6474 kg and circled the Earth once every 89.7 minutes and an inclination angle of 65 degrees.
- B. According to a signal from the control center, the spacecraft was disconnected from the satellite and set off.
- The researchers had additional goals:
- A. To test methods for launching satellites into interstellar orbit.
- B. to check the conditions of radio communication for long distances in space.
- third. Scan the guidance options of a space station to most accurately explore the circumference of the solar system.
- d. to carry out plans of physical observations in space.
Venera 2
Venera 2 was launched on November 12, 1965 and reached its destination on February 27, 1966. The spacecraft was supposed to make a soft landing on the surface of Venus. Instead, she missed it by 24,000 km. When you were close to Venus the connection with you was broken. The spacecraft had to make physical measurements of the planet and photograph its face from close up and from afar. The spacecraft had television cameras. The diameter of the spacecraft is 88.9 cm. There are several similarities between this spaceship and the previous one:
A. Chemical batteries and solar collectors worked in both.
B. Both were launched in a similar way.
third. Both are heavy spaceships. The weight of Venera 2 was 963 kg.
Venera 3
Venera 3 was launched on November 16, 1965 and it reached Venus 106 days later, after a journey of 280 million km and it crashed on it on April 1, 1966. Its flight path was the same as that of Venera 2. On December 26, 1965 a correction was made to the flight path . Before launch, the spacecraft is disinfected to prevent contamination of the planet by organisms from Earth. Since Venus has its own atmosphere, it was necessary to equip the spacecraft with adequate protective equipment. The spacecraft was equipped with a parachute and a special isolation device. The spaceship also had a powerful transmitter that broadcast on long waves. The weight of the spacecraft is 960 km.
The spacecraft carried a flag with the Soviet symbol - the hammer and sickle, as well as a small globe of the Earth. Inside the globe was a board with a map of the solar system on one side and a symbol of the USSR on the other. The spacecraft was supposed to land in the center of the planet. Shortly before landing contact with you was lost and because of this the spaceship crashed instead of landing on it. The impact was thousands of kilometers away from the target. Venera 3 had to transmit data on the temperature and atmospheric pressure prevailing on the ground.
Venera 4
Venera 4 was launched on June 12, 1967 and it reached its destination about 4 months later on October 18, 1967. The spacecraft traveled 320 million km and weighed 1150 kg. The launch was made from a stationary terrestrial orbit and on July 29, at a distance of 12 million km from the Earth, a successful path correction was performed. The position of the spacecraft during the flight is determined according to its position in relation to the Earth, the Sun and the planet Canopus.
The spacecraft was built in two parts, the orbital compartment and the landing compartment. The orbital cell contains navigation engines, sensing devices for orbit corrections, gyroscopic devices, parabolic antenna, directional antenna, electro-optical sensing devices for height control from the planet's ground, solar collectors, magnetometer, cosmic particle counter, electronic equipment for experiments, fuel supply system and meter heat to maintain the internal temperature.
The spaceship itself did not land, but approached the limits of the atmosphere and ejected an instrument chamber with a diameter of 102 cm and a weight of 382 kg that was built for a soft landing. The cell protected by ablative thermal cooling descended to the surface of Venus and slowed down due to aerodynamic resistance. Finally, at an altitude of 25 km from the ground, three parachutes opened, one after the other, which slowed the speed of the fall to 3 meters per second (also taking into account the density of the atmosphere). When the main parachute opened, the antenna, radio receiver and telemetry devices went into action. The landing took 90 minutes. And during all that time the landing gear transmitted a large amount of information. The cell stopped transmitting while descending. The reason for this lies in the high temperature created when it entered the atmosphere and the atmospheric pressure that caused it to collapse.
From the data broadcast to Israel it turned out that Venus is smaller than they thought. A magnetic field is almost non-existent and it does not have any radiation belts like those of the Earth (Van Allen belts). The atmosphere is 15-22 times denser than Earth's. Atmospheric pressure and temperatures vary considerably with altitude changes. The temperatures were between 40 and 280 degrees. The atmosphere contains 90% CO2, 7% nitrogen, and low concentrations of oxygen and water vapor. A halo of oxygen and nitrogen do not exist at all. The star itself resembles a fiery desert of stones and in its composition it resembles the earth.
The lessons learned from the flight were that the isolation and sensitivity of the instruments should be improved and if possible, the decrease in height of the spacecraft while it is in the atmosphere should be accelerated by reducing the parachutes. This method will allow deeper penetration and closer to the surface.
Venera 5, Venera 6
The partial success of Venera 3 and the full success of Venera 4 encouraged Russian space scientists and encouraged them to move to intensive study of Venus. The space scientists wanted to investigate the possibility of the existence of earthly animals in the conditions of Venus. For this purpose, two spaceships, Venera 5 and Venera 6, were launched to collect as much information as possible from both sides of the planet and based on that to establish research laboratories. Each spacecraft weighed 1130 kg, of which 405 kg was the lander.
The two spaceships stood up well to the hardships of the interstellar journey of 350 million km. The lander of Venera 5 was separated from the mother spacecraft at a distance of 37,000 km from Venus, Venera 6 was separated at a distance of 25,000 km. The mother landers continued on their way at a speed of 11.18 km per second. This speed required the strengthening of the landing gear so that it could withstand the load of g450 and the heat generated during entry into the atmosphere.
The aerodynamic braking of the landers continued until their speed was reduced to 210 meters per second, and then their parachutes deployed. The temperature on their outer wall reached thousands of degrees, but they were protected by ablative layers. Considering the Venera 4 data that showed that the atmosphere is much denser than the value that was accepted before and the need to increase the speed of their descent after the parachutes are deployed, in order to reduce as much as possible the risk of the devices being damaged by the external heat. The area of the landing parachutes was reduced by 1/3 compared to that of Venera 4 and the average rate of descent to the ground was 10 meters per second. The descent to the ground lasted 50 minutes.
The findings of the landers were not substantially different from those of Venera 4. The CO2 concentration was between 93% - 97%. The nitrogen with other inert gases between 2% - 5% and the oxygen content does not exceed 0.4%. The water vapor content is very low. The height of the atmosphere is estimated at 36 km. Corresponding measurements of the spacecraft using a wireless altimeter at the same temperatures and external pressures revealed height differences of 12-16 km. The measurements made at a distance of only 300 km from each other indicate height differences on the surface of Venus. The landers measured a pressure of 25-27 atmospheres and the temperature range 25 degrees to 320. Each of the landers carried with them a picture of Lenin and a symbol of the USSR.
Venera 5
Venera 5 was launched on January 5, 1969. The course of the flight is divided into two stages. In the first stage, the spacecraft was put into a terrestrial orbit - a parking orbit to test the spacecraft's systems. The spacecraft stayed in this orbit for 79 minutes, and when it was found to be safe, it was launched towards the planet. The spacecraft traveled 350 million km. On May 16, the spacecraft arrived at Venus. 53 minutes after entering the atmosphere, the spacecraft stopped its transmissions. The intrusion was on the night side of Venus. In total, the spaceship traveled 36 km in the atmosphere.
Venera 6
Venera 6 was launched on January 10, 1969 and it arrived at Venus 24 hours after Venera 5, it penetrated the atmosphere on its night side and at a distance of 300 km from Venera 5. The spacecraft transmitted data for 51 minutes, and traveled 37.8 km in the atmosphere.
