Mars 2M No.521, also known as Mars M-69 No.521 and sometimes identified by NASA as Mars 1969A, was a

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

spacecraft which was lost in a launch failure in 1969. It consisted of an orbiter. The spacecraft was intended to image the surface of Mars using three cameras, with images being encoded for transmission back to Earth as television signals. It also carried a radiometer, a series of spectrometers, and an instrument to detect

water vapour (99.9839 °C) , - , Boiling point , , - , specific gas constant , 461.5 J/( kg·K) , - , Heat of vaporization , 2.27 MJ/kg , - , Heat capacity , 1.864 kJ/(kg·K) Water vapor, water vapour or aqueous vapor is the gaseous pha ...

in the

atmosphere of Mars The atmosphere of Mars is the layer of gases surrounding Mars. It is primarily composed of carbon dioxide (95%), molecular nitrogen (2.8%), and argon (2%). It also contains trace levels of water vapor, oxygen, carbon monoxide, hydrogen, and no ...

. It was one of two Mars 2M spacecraft, along with

Mars 2M No.522 Mars 2M No.522, also known as Mars M-69 No.522 and sometimes identified by NASA as Mars 1969B, was a Soviet spacecraft which was lost in a launch failure in 1969. It consisted of an orbiter. The spacecraft was intended to image the surface of Mar ...

, which was launched in 1969 as part of the

Mars program The Mars program was a series of uncrewed spacecraft launched by the Soviet Union between 1960 and 1973. The spacecraft were intended to explore Mars, and included flyby probes, landers and orbiters. Early Mars spacecraft were small, and launch ...

me. Neither launch was successful. The Mars 2M probes were originally intended to consist of both an orbiter and a lander. Time constraints did not permit the development of a soft lander, so engineers decided to simply use a hard lander that would crash into the Martian surface but gather data during its descent. At first, a modified Luna E-8 bus was to be used for the spacecraft, however it had a number of limitations that made it unsuitable for the long journey to Mars. Halfway through the project, Lavochkin Bureau design chief Georgi Babakin decided to simply discard the Luna E-8 derived probe and design a completely new one from scratch. However, the 2M probes ended significantly heavier than intended and engineers also ran out of time to conduct drop tests of the lander, so that part was abandoned which left only the orbiter. If successful, this would still be a major propaganda success for the Soviets as NASA was nearly three years away from attempting a Mars orbiter. As 1968 drew to a close, the project was lagging behind schedule and the US was also making significant headway in the space race with

Mariner 6 and 7 Mariner 6 and Mariner 7 (Mariner Mars 69A and Mariner Mars 69B) were two unmanned NASA robotic spacecraft that completed the first dual mission to Mars in 1969 as part of NASA's wider Mariner program. Mariner 6 was launched from Launch Complex ...

scheduled to launch to Mars early in the next year and

Apollo 8 Apollo 8 (December 21–27, 1968) was the first crewed spacecraft to leave low Earth orbit and the first human spaceflight to reach the Moon. The crew orbited the Moon ten times without landing, and then departed safely back to Earth. These ...

taking astronauts into lunar orbit. The Kremlin wanted the Mars probes readied as soon as possible and the second of the two probes was completed in the middle of January. Despite doubts that the probes were ready to fly, they were delivered to Baikonour.

Launch

Mars 2M No.521 was launched at 10:40:45 UTC on March 27, 1969, atop a Proton-K 8K78K

carrier rocket A launch vehicle or carrier rocket is a rocket designed to carry a payload (spacecraft or satellites) from the Earth's surface to outer space. Most launch vehicles operate from a launch pad, launch pads, supported by a missile launch contro ...

with a

Blok D Blok D (russian: Блок Д meaning Block D) is an upper stage used on Soviet and later Russian expendable launch systems, including the N1, Proton-K and Zenit. The stage (and its derivatives) has been included in more than 320 launched roc ...

upper stage, flying from Baikonur Cosmodrome Site 81/23. First and second stage burn went normally, followed by payload shroud jettison. However, third stage ignition did not occur on time and reports filtered back to the launch center that the booster had exploded. Investigation found that an imbalanced rotor in the third stage oxidizer turbopump had started a fire, which led to loss of thrust and vehicle breakup. The remains of the third stage and probe impacted in the

Altai Mountains The Altai Mountains (), also spelled Altay Mountains, are a mountain range in Central Asia, Central and East Asia, where Russia, China, Mongolia and Kazakhstan converge, and where the rivers Irtysh and Ob River, Ob have their headwaters. The m ...

. Even more difficult for Soviet engineers was the news that

Mariner 7 A sailor, seaman, mariner, or seafarer is a person who works aboard a watercraft as part of its crew, and may work in any one of a number of different fields that are related to the operation and maintenance of a ship. The profession of the s ...

had been successfully launched from Cape Canaveral a few days earlier, and their next Mars launch also failed a few days later.

Scientific Instruments

The scientific instruments were: *

Radiometer A radiometer or roentgenometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Generally, a radiometer is an infrared radiation detector or an ultraviolet detector. Microwave radiometers operate in the microwave w ...

* Instrument to measure water vapor levels * Ultraviolet spectrometer * Gamma spectrometer * Hydrogen mass spectrometer * Helium mass spectrometer *

Spectrometer A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the ...

* Low energy ion spectrometer *

Imaging System Imaging is the representation or reproduction of an object's form; especially a visual representation (i.e., the formation of an image). Imaging technology is the application of materials and methods to create, preserve, or duplicate images. ...

(With three on board cameras)

References

External links

Cornell University's Mars Missions page

Professor Chris Mihos, Case Western Reserve University {{Mars spacecraft Spacecraft launched in 1969 1969 in the Soviet Union Mars program

Launch

Scientific Instruments

See also

References

External links