«Марс-2»: первый на Красной планете

On November 27, 1971, an event occurred that forever changed the history of space exploration. On this day, the Soviet automatic station «Mars-2» reached the surface of the Red Planet, becoming the first man-made object to land on Martian soil. This mission was launched just ten years after Yuri Gagarin's legendary flight.

On May 19, 1971, the «Proton-K» launch vehicle with an upper stage lifted off from the Baikonur Cosmodrome, placing the «Mars-2» station on a trajectory to Mars. The orbital module, weighing 4625 kg, was equipped with a complex of scientific instruments, and the descent module, weighing one ton, was to land on the Martian surface. A special feature of the preparation for this mission was the extremely tight deadlines. The favorable launch window to Mars opened for only a few weeks every two years. Soviet engineers had to work in very harsh conditions to prepare two identical stations at once — «Mars-2» and its backup — «Mars-3».

The orbital module was equipped with:

Of particular note was the 167 kg control system created by the Research Institute of Automation and Instrument Engineering. Its "brain" was the on-board digital computer C-530, which consumed 800 W of power. In addition to orientation to the Sun, at a considerable distance from Earth (approximately 30 million kilometers), simultaneous orientation to the Sun, the star Canopus, and our planet was carried out.

An Epic Six-Month Journey

The journey to Mars took more than six months. During this time, the station covered a colossal distance of about 60 million kilometers. The first scientific data began to arrive as it approached the planet. At a distance of 20 million kilometers from Earth, on-board instruments recorded an extended "tail" of the Earth's magnetic field — an area where the magnetic field lines of our planet extend far into space.

Data on the interplanetary environment were of particular value. For the first time in history, scientists obtained accurate measurements of changes in the density and temperature of solar wind particles as they moved away from the Sun. In total, more than one hundred communication sessions were conducted during the interplanetary flight, during which telemetry and scientific measurement results were transmitted to Earth.

A Fateful Encounter with the Red Planet

On November 27, 1971, «Mars-2» successfully entered orbit around Mars. However, it was at this moment that a dust storm began, which subsequently engulfed the entire planet. The atmosphere unexpectedly became much denser, and visibility dropped to almost zero. The descent module began to descend at an angle significantly exceeding the calculated parameters. Automatic systems could not correct the trajectory — the braking mechanisms could not cope with the increased aerodynamic drag. As a result, the module entered the atmosphere at an excessively steep angle and crashed into the surface at high speed in the Tharsis Highlands region, the exact coordinates of which are 4° north latitude and 47° west longitude. Inside the descent module were special metal pennants with the USSR coat of arms — the first man-made objects to reach the surface of another planet in the Solar System.

After the loss of the descent module, the orbital station continued its work. For eight months, until August 1972, it made exactly 362 revolutions around Mars, collecting invaluable scientific data.

The infrared radiometer compiled detailed temperature maps of the planet's surface. Special photometers carefully studied the distribution of carbon dioxide in the atmosphere. Ultraviolet sensors conducted a detailed analysis of the composition of the upper layers of the Martian atmosphere. And the installed cameras recorded all the changes during the ongoing global dust storm, which lasted until January 1972. All these comprehensive studies made it possible for the first time in history to obtain reliable data on the Martian atmosphere and climatic features. Of particular scientific value were the unique observations of the giant dust storm, which helped to understand the dynamics of atmospheric processes on the Red Planet.

Technical Difficulties and How They Were Overcome

In the modern era, when rovers transmit panoramic images in high resolution to Earth, it is difficult to fully appreciate the colossal difficulties faced by the creators of «Mars-2». In 1971, engineers worked in conditions of acute shortage of critical information: accurate maps of the Martian surface were completely absent. Data on the real density of the atmosphere were extremely approximate, and the possibilities for rapid flight correction were practically non-existent. The computing power of on-board computers was incomparable to modern standards. All systems had to operate in fully autonomous mode. At the same time, the total mass of scientific equipment was only a few tens of kilograms — negligibly small by modern standards.

Historical Significance of the Mission

Despite the emergency landing, the «Mars-2» mission proved the fundamental possibility of implementing a number of key technologies:

The orbital module operated in Martian orbit for eight months — until its resources were completely exhausted. Today, its exact location remains unknown — perhaps it continues its silent rotation around the Red Planet.

This outstanding mission opened a new era in the exploration of the Solar System and forever inscribed the USSR in the history of space achievements. All subsequent Martian programs — both Soviet and American — are, to one degree or another, a continuation and development of this pioneering flight.

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