The American space program for 1971 included the launch of two spacecraft to Mars, Mariner 8 and Mariner 9, and putting them into orbit around it for 90 days, Mariner 8 also fell victim to the curse of Mars when the launcher and its crew fell into the sea shortly after launch but Mariner 9 was a success story
Mariner 8, Mariner 9
The American space program for 1971 included launching two spacecraft to Mars, Mariner 8 and Mariner 9, and putting them into orbit around it for 90 days. These spacecraft are similar in structure to previous spacecraft of this series, except that their weight was greater. The weight of each spacecraft is close to 1 ton, of which 540 kg is the body of the spacecraft on its equipment and over 400 kg of fuel. This amount of fuel is needed to run the spacecraft's engine for 15 minutes to put it into orbit around Mars. The orbit was designed so that even if a malfunction occurs in the control mechanism, the spacecraft will not crash on the ground of Mars, before circling it for at least 17 years, in order to prevent the contamination of Mars by living creatures from Earth.
Each spaceship has five instruments:
1. Color TV cameras - one wide-angle camera for general photography of 70% of the surface of Mars. The second camera is telescopic and the shooting angle is narrow. This camera is designed for 5% detailed photography of the surface of Mars.
2. Infrared radiometer
3. Ultraviolet spectrometer
4. Particle detector
5. High frequency radio receiver
The investigation of Mars is done simultaneously by all the measuring instruments, so that it is possible to accurately coordinate the various data transmitted to the Earth and to stand up to the nature of the surveyed area. This set of instruments is designed to carry out a detailed survey of the Martian surface and extract valuable information about various phenomena related to the planet and they are:
A. Observe daily and seasonal changes on Mars.
1. To stand for the nature of the yellow clouds covering large areas on the surface of Mars for a month or more.
2. To stand for the nature of the white clouds that appear here and there in varying degrees of density for more or less short periods.
3. To stand for the nature of the dark gray clouds that can indicate volcanic activity.
4. Stand on the composition of the white domes in poles, water or dry ice.
5. "Dark waves" - cyclical changes in the face of the star, bright in summer and dark in winter. Hypotheses have been put forward to explain the phenomenon. One hypothesis says that it is vegetation. A second hypothesis says that the reason for the darkening of the surface is an increase in the number of special living creatures in response to an increase in temperature and humidity. According to a third hypothesis, at the beginning of spring there are changes in the winds and these cause a redistribution of the dust on the surface of Mars as well as the properties of reflecting light from it.
B. To examine the atmosphere and its composition and find out if primitive life forms exist at all on the surface of Mars.
third. Collect data on the magnetic field of Mars, the shape of Mars and its density in different regions.
d. The orbits of Phobos and Demos, the moons of Mars, will become more precisely determined by the movement of the spacecraft.
God. find landing sites.
The duration of the spacecraft's flight to Mars was planned for six months and the length of the flight path was 460 million km. The failure of Mariner 8 led to changes in the work plan and some of its tasks were transferred to Mariner 9. As a result, the total planned photographs of Mariner 9 increased to 6,000. Both spacecraft were launched by Atlas Centaur model launchers. Close to the launch of these spacecraft, the Soviet Union launched two of its own spacecraft to Mars. It was agreed that the space scientists of the two countries would exchange information on the findings of the spacecraft. For this purpose, a telex line was established between the two control centers.
Mariner 8
Mariner 8 was launched on April 9, 1971. Five minutes after launch, the launcher fell out of control, deviated from its course and fell into the Atlantic Ocean. The spacecraft was supposed to reach Mars in November this year and enter orbit around it. It was supposed to be an elliptical orbit whose distance from the ground is 1,800-17,000 km. The whole coffee lasts 12 hours. The flight path was designed so that the spacecraft would map 70% of the surface.
Mariner 9
Five times the launch of Mariner 9 was postponed. Once and only, on the day of the launch, due to a technical fault in the electrical system and the other times due to the failure of Mariner 8. This failure resulted in a change of caution. The source of the problem was checked several times and only after they confirmed its nature and promised that it would not happen again was Mariner 9 launched. The launch was on April 30, 1971. On June 4, 300,000 km from Earth, the spacecraft's engine was turned on for five seconds to make a correction to the flight path. The maneuver was performed successfully and with great precision. The transmitter for the maneuver was sent from Australia. On June 30, the nitrogen consumption of the stabilization engines began to increase beyond what was expected due to a malfunction in an electronic circuit and there was concern about the fate of the flight. With the repair of the fault a few days later, the concern was removed. 12 days before entering orbit around Mars, on November 2, the antenna aimed at Earth was hit by dust grains. After five hours of hard work, the antenna was installed and contact with it was restored.
On November 14, after a journey of 176 days, the spacecraft's engine was activated for 15 minutes, which put the spacecraft into an elliptical orbit around Mars. The distances of the route from the ground are 1,389 to 17,816 km. The whole coffee lasted 12 hours and 3 minutes, 4 minutes less than expected. The inclination angle is 64.28 degrees. This course was decided upon following the failure of Mariner 8. According to the original plan, the course of Mariner 9 around Mars should have been 1000-41,500 km. The entire coffee lasts 32.8 hours. Once every 5-6 hours Mariner 9 must return to the same selected areas to make a more detailed observation.
On the 23rd and 24th of September, a huge yellow dust storm developed on Mars, such a storm carried by winds whose speed exceeds 300 km/h takes place every year at this time of the year in the southern hemisphere. This is the summer season, when the polar ice cap melts. Signs showed that in mid-October the storm weakened and it strengthened again in November. It has been suggested that this storm is caused by the evaporation of CO2 from the ice cap of Mars. Researchers have been given a rare opportunity to reconcile this storm.
Two hours after entering the runway, Mariner 9 began to broadcast television photographs that it had taken on November 11 and 13 and stored them on its computer. These photographs were blurry and unclear due to the storm. The 33 photographs were broadcast in the second round and, like their predecessors, were indistinct, especially those taken at an altitude of 1,388 km above the South Pole. The rim of the star can barely be seen through the dust mantle. The horizon line was highlighted only after the computer processed the photographs to highlight contrasts. The researchers hoped to see in the photographs the spots observed by Mariner 6 and Mariner 7. These spots become clearer as the days on the surface of Mars increase.
Photographing the surface of Mars began on November 10 from a distance of 861,000 km from it. The second series of photographs was taken from a distance of 210,000 km and continued until the spacecraft reached a distance of 112,000 km from the face of the star. These photographs were broadcast to Israel only after the spacecraft entered orbit around Mars. The importance of these photographs is that they include the highest quality images of the Martian moons Phobos and Demos.
First week, November 16 to 22
On November 16, the flight route was slightly changed. The perihelion was 1,379 km with the spacecraft facing east at 9 degrees. This orbit made it possible to photograph the surface of Mars all in stripes that overlap each other at their edges - two series per day. The duration of the coffee is shortened to 12 hours. Despite the difficulty of seeing, new and surprising things were discovered. The prevailing temperature on the surface of Mars is 127 degrees below zero, but at a certain point it is 10 degrees higher. Underground heat emanates from this place and is subject to sharp temperature fluctuations.
In an attempt to overcome the poor visibility, the shooting angles were changed and different light filters were tried. The cameras were mainly directed towards the South Pole. There were partial clearings and indeed in these images the South Pole appears to be covered with an ice cap, although smaller because of the summer. From the control center, the Russian space scientists were given data on the weather conditions to guide them in the navigation of the Mars 2 and Mars 3 spacecraft.
November 17- The clearest photographs received on this day testify to the nature of the seasonal changes on Mars.
November 20 - The measurements made by the spacecraft showed that Mars is egg-shaped with a bulge in the equatorial region. At the equator there are sensors that cause anomalies in the force of gravity and jumps of the spacecraft in its orbit. This phenomenon was first detected on Earth's moon, when spacecraft began orbiting it. Water vapor floats over the South Pole. It turned out that the dust storm takes place at a height of five kilometers above the ground and the dust particles reach a height of 30 kilometers.
Due to the storm that hit Mars, new operations were planned that were different from the original ones, but no less important. The TV cameras looked for windows in the dust storm, to photograph the surface. This method has proven itself. Mariner 6 and Mariner 7 photographed hills and craters covered in frost, Mariner 9 showed that these hills were "clear" of frost, but the craters, on the other hand, disappeared. The surface of Mars in these places was smooth.
The infrared radiometer showed that quartz and granite are found on Mars. The interior of Mars was once liquid. Over time the light elements floated and rose to the surface and hardened.
Second week, November 23 to 29
Mariner 9 also tried its hand at photographing the Martian moons, Phobos and Demos. Demos was photographed on November 26 from a distance of 9000 km. The photo shows its light side in detail. It turned out that the moon has an elliptical shape. The short axis is 9.6 km long and the long axis is 16 km. Lademous face lines and mysterious light spots. It seems to be torn or disconnected from somewhere.
They tried to photograph Phobos the great moon a day later on November 27. In this attempt, the spacecraft was 1,600 km away from him. This attempt was unsuccessful. This was expected because the orbit of Phobos was unknown and for this reason a photo attempt made on November 28 was also unsuccessful. Only on November 29 did they manage to photograph it from a distance of 6,000 km.
Third week, November 30 to December 6
Phobos was photographed once more on November 30. The resulting photographs were of high quality. As in the photograph of Damos, in this case too it turned out that the moon is bigger than they thought. It is also elliptical. The length of the short axis is 19.3 km and the long axis is 27.3 km. In the photographs you can see one large crater. The photographs were taken from distances ranging from 4,500 to 14,400 km. The cameras were pointed towards Mars. Four peaks were observed with their mouths resembling those of volcanoes.
End of phase I, transition to phase B
On March 6, Mariner 9 finished its original program. A day later a new phase began. The frequency of filming was reduced to 42 per day. In contrast, new research areas were carefully selected. On March 18, on the 250th lap, a malfunction was discovered in the spacecraft. The computer stopped working and the flow of photos stopped temporarily. The computer resumed its operation on March 23.
On April 4, the spacecraft entered the region of Mars' shadow (relative to the Sun). As a result, in part of its route, its batteries were not filled with a sufficient amount of electrical power and there were interruptions in transmissions. For two months, until June 8.5, only the most essential systems for research were activated - the experiments in astrophysical mechanics and eclipses. Only the telemetry devices worked. The signal rate slowed to 9 per second due to the use of the low gain antenna and the increasing distance between Earth and Mars. By April 85, Mariner 70 covered XNUMX% of the face of Mars in its photographs instead of XNUMX% as planned.
Mariner 9 came out of the "shadow" on June 4 and resumed its activities. Compared to its initial broadcasts, the spacecraft's activity was limited. A large amount of gas was required to maintain the correct orientation of the solar arrays and the high praise antenna. Because of this, the transfer of information to Israel was reduced to twice a week until the beginning of August. Each broadcast lasts 8.5 hours including the broadcast of 30 TV pictures. This activity continued until the moment when the distance between Earth and Mars began to increase towards its maximum - 244 million km. At that moment, the broadcasts were frozen for 6 weeks until the end of September. During this period, attempts were made in some of the details of the theory of relativity related to the effects of gravity on electromagnetic waves. On October 27, 1972, Mariner 9 completed its missions. Her findings showed that the chance of finding life on Mars is 50%. A total of 7,329 photographs were broadcast to Israel.
Mariner's findings 9
Tectonics and Volcanic Activity
In its structure, Mars is similar to Earth, except that it is in a relatively early period in its development. On its surface there is probably one huge continent in the southern hemisphere and a waterless "ocean" in the northern hemisphere.
The Northern Hemisphere is almost completely flat because it is covered with rocks (probably lava flows) that are much younger than the scarred land area. Some of the detailed pictures of the smooth lowland area remind of the "days" of the moon. It is possible that on the surface of Mars a process similar to the formation of the sea floor on Earth is taking place by volcanic activity and the spreading of lava.
The southern hemisphere is full of craters and mountains. The continent is three kilometers higher than the "ocean". The height difference was discovered by measuring atmospheric pressure at different heights, radar mapping and different gravimetric determinations on the surface of Mars. Vigorous volcanic activity occurs in the Tharsis region and the Nix Olympia volcano. Many inactive volcanoes found on the surface of Mars testify to a long period of volcanic eruptions from the active volcanic areas. To the east stretches a fault system 6,000 km long that runs through the mountainous region. It is possible that this system marks the beginning of the separation of a separate continent.
Along the equator of Mars three types of channels can be distinguished. One channel seems to meander like a river and in several places smaller channels join it. The system is not at all similar to the product of lava flows, but to the remains of an ancient river. A second type of channel looks like a plexus of channels that meet each other and separate again similar to the great tropical rivers on Earth. A third type is found in the mountainous area, in small, branching channels that tend to disappear downhill. The three types of channels extend from the high areas to the low areas.
erosion
The wind action on the surface of Mars is extremely vigorous and the reasons for this are the high wind speeds and the large amounts of dust in the atmosphere that erode the surface. The equatorial regions are relatively dust free. A lot of dust can be found from the poles up to the latitude 30 degrees north and south. A multi-layered structure in the North Pole in particular can testify to the action of the wind which results in the deposition of dust particles of different sizes in different periods. It could be that the contrasts between the light stripes and the dark stripes are contrasts of light and shadow on mountains with a structure of terraces, steps.
Some of the various surface phenomena can be explained. Assuming that at a great depth, about two kilometers, below the surface, the ground is frozen like the permafrost found in Siberia or northern Canada. The fact that the channels and basins in many areas of Mars are of uniform depth can be explained by the fact that at great depth, the ice caused the dust particles of the Martian surface to stick together, while the unfrozen dust, found in less cold areas of the ground, remained exposed to the erosive actions of the wind. Large craters, the bottom of which is covered with dunes.
Geomorphology
In the photographs you see huge craters and many mountain peaks. A careful study of the photographs shows that the craters are volcanic and resemble the craters of the Earth's extinct volcanoes. The flat plateaus are covered in a network of fissures and in one area you can see a deep fault such as the Syrian-African fault. The fragments look as if they were created by the movement of huge blocks made of volcanic material. There are also other clear signs of volcanic eruptions that probably occurred in late geological time.
An area that is 370 km wide and 480 km long, located 500 km south of the equator, appears to be a huge ground depression, probably created by the settling of the soft crust of Mars and the erosion of the wind. In the Nix Olympia crater, which is 60 km in diameter and 8 km deep, signs of internal volcanic activity are visible, probably in the form of lava. At the foot of the volcano are steep cliffs. The diameter of the base of the volcano is 500 km and it rises to a height of 27 km above the ground. In Lesbius Lakos and on the faces of the craters, strange and different formations are visible. On the Noctus Lakos plateau there is a network of canyons created by fractures in the Martian crust. Clear signs of erosion can be observed.
Canyons that are 1,870 km long look like streams of water. At the South Pole you can see pits and basins with a diameter of up to 16 km. They are similar to the pits and basins on Earth that were formed by the subsidence of glaciers. The photographs show canyons with a diameter of 21 km and a depth of 3 km. You can also see a large canyon that is 500 km long and 60 km wide. There are short and long valleys on Mars. The length of the short ones is 4,000 km, and the longest valley is 120 km long, 6.4 km wide and XNUMX km deep.
The surface of Mars is porous and fissured with trenches full of craters that are 1,700 km long. Mars is covered with strange light and dark spots. These spots are probably the product of the accumulation of dust carried by the wind. Its mobility and light reflection are different from the dust on the surface of the ground. The infrared spectrometer shows that the dust and probably also the material from which the surface of Mars is made is very rich in silica.
The findings of Mariner 9 led to the belief that the Martian canals seen in telescopes at the end of the nineteenth century and the beginning of the twentieth century are nothing more than the foundations of rivers that have been disrupted in the meantime. It seems that on the surface of Mars there were good conditions for the creation of rivers and lakes - atmospheric pressure and temperature. The findings show that the Earth, Venus and Mars have common properties. Venus may have had formations similar to the canals of Mars and Earth. These findings were discovered during observations made by the United States from Earth with the help of the Deep Space Network and the Russian Venera spacecraft.
Meteorology
The atmospheric and meteorological processes of Mars differ considerably from their corresponding processes on Earth. The height of the main mass of the atmosphere is 10 km and the tops of the mountains peek out from it. The distance between the high places and the low places is 13 km. The temperatures are extreme and the temperature drops are particularly large. The dust storm that raged on the surface of Mars in the first days of Mariner 9's operation showed that the dust content on the surface of Mars is higher than seen by terrestrial observations. The dust is part of the mechanism that causes seasonal and perennial changes.
The new photographs of the South Pole's cap reinforced the assumption that the ice cap is made of dry ice. In the first two weeks of its observations, Mariner 9 discovered noticeable changes in the circumference of the dome. The dome looks thinner at the ends. Various signs show that in the past thick layers of ice accumulated in the area of the dome. In one of the photographs, formations of a glacier structure are visible, implying that extensive ice fields may be under the dry ice. And indeed, in later photographs, this assumption was adjusted. There are two types of ice on Mars. The South Pole is covered with a permanent layer of ice that covers an area of 300 square kilometers. This layer is covered in winter with a layer of dry ice that covers an area of 3,000 square kilometers. The temperatures at this time of the year reach 110 degrees below zero.
On June 23, the spacecraft photographed a white area near the North Pole over 1,000 km long that probably contains frozen water. The average temperature range is between 27 degrees at the equator and 123 degrees below zero at the poles. The spacecraft's cameras picked up changing forms of clouds mainly in the north, although also above the volcanoes, they may contain water.
Long after Mariner 9 completed its mission, a proposal was made to test long-term cyclical changes on the surface of Mars. According to this proposal, slow changes in the geometry of Mars' orbit around the Sun can cause colder weather for periods of tens of thousands of years. After that, pleasant weather and a return to the cold weather. According to this theory, once every 25,000 years the polar axis changes its position. The poles are exposed to strong radiation from the sun and evaporate. Monsoon winds and torrential rains attack Mars, filling the valleys and basins with water, creating lakes and probably short-lived seas, while the frozen CO2 can turn into fairly compressed air. During the cold ice ages, water and CO2 freeze and concentrate at the poles. During these ice ages, Mars excels in prominent ice caps and a thin atmosphere.
atmosphere
The atmosphere consists mainly of CO2, tiny amounts of water vapor and their decomposition products, and ozone. The highest concentration of water vapor is over the South Pole. Atmospheric pressure is about 5.5. millibar. The ionosphere begins sharply at an altitude of 100 km and at an altitude of 150 km its density reaches a peak density of 5 10 charged particles per cm300. At higher altitudes this density is sharply reduced. At an altitude of 1,000 km there are no more than XNUMX electrons in each cmXNUMX of atmosphere.
moons
The moons are covered with a large number of craters. Their shape is not uniform and normal. Both moons were broken by very strong impacts from meteorites. Phobos is shaped like a potato.
Biology
A re-examination of the Mariner 9 findings in 1975 raised the confidence of American space scientists that any form of life is possible on Mars. It turned out that the temperatures in the warm regions of Mars are more comfortable for life than they first thought and that the amount of water vapor on its surface is greater than they thought. This information strengthened the hypothesis that bacteria could exist on Mars.
There is another possibility for the biological development of Mars. From atmospheric measurements at different altitudes it is possible to learn about the escape rate of oxygen from the atmosphere. Based on these data it is possible to reconstruct the composition of the atmosphere in the past. It can be assumed that in the distant past Mars resembled the Earth. It had oceans, active volcanoes and atmospheric pressure the same as Earth's. If this period lasted for quite a long time there may have been life on his face. The question is whether they were able to adapt to the new and difficult conditions that were created, a thin and dry atmosphere. If they have indeed adapted to this, it is possible that they live in the depths of the earth and extract the oxygen and CO2 necessary for their existence from the minerals in the ground. There they also have nitrogen to create amino acids that build their bodies. Such creatures come to the surface for photosynthetic needs only when there are sandstorms on the surface of Mars that protect them from ultraviolet radiation.
At the end of its mission, contact with Mariner 9 was proactively cut off and it remained in orbit around Mars. It should fall on his face in 2020 at the earliest.
