astronomy

Mars 4

Mars 4 is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Mars 4 rather than just read about it. In short: Mars 4 (Russian: Марс-4), also known as 3MS No.52S was a Soviet spacecraft intended to explore Mars. A 3MS spacecraft launched as part of the Mars programme, it was intended to enter orbit around Mars in 1974.

Key takeaways

Mars 4 belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Mars 4 to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Mars 4 from memory before moving on to harder problems.

Reference excerpt

Mars 4 (Russian: Марс-4), also known as 3MS No.52S was a Soviet spacecraft intended to explore Mars. A 3MS spacecraft launched as part of the Mars programme, it was intended to enter orbit around Mars in 1974. However, computer problems prevented orbital insertion from occurring.

Spacecraft The Mars 4 spacecraft carried an array of instruments to study Mars. In addition to cameras, it was equipped with a radio telescope, an IR radiometer, multiple photometers, polarimeters, a magnetometer, plasma traps, an electrostatic analyzer, a gamma-ray spectrometer, and a radio probe. Built by Lavochkin, Mars 4 was the first of two 3MS spacecraft launched to Mars in 1973, being followed by Mars 5. A 3MS was also launched during the 1971 launch window as Kosmos 419. However, due to a launch failure, it failed to depart Earth orbit. In addition to the orbiters, two 3MP lander missions, Mars 6 and Mars 7, were launched during the 1973 window.

Launch Mars 4 was launched by a Proton-K carrier rocket, a Blok D upper stage, flying from Baikonur Cosmodrome Site 81/23. The launch occurred at 19:30:59 UTC on 21 July 1973, with the first three stages placing the spacecraft and upper stage into a low Earth parking orbit before the Blok D fired to propel Mars 4 into heliocentric orbit bound for Mars. Shortly after performing a course correction on 30 July 1973, two onboard computers failed, leaving Mars 4 unable to perform maneuvers. As a result of this, it was unable to enter orbit around Mars. Twelve photographs were taken on 10 February 1974 from 15:32 UTC to 15:38 UTC as the probe flew past Mars with a closest approach of 1,844 kilometres (1,146 mi) at 15:34 UTC.

Scientific Instruments Mars 4 orbiter carried 15 scientific instruments on board to study Mars from orbital trajectory

Atmospheric Radio-probing Instrument Radio Telescope Infrared Radiometer Spectrophotometer Narrow-band Photometer Narrow-band Interference-Polarization Photometer Imaging System Photometers Two Polarimeters Ultraviolet Photometer Scattered Solar Radiation Photometer Gamma Spectrometer Magnetometer Plasma Traps Multichannel Electrostatic Analyzer

See also List of missions to Mars Timeline of artificial satellites and space probes

References

Illustrations

Worked examples

Example 1 — a first encounter with Mars 4

Start with the simplest possible case. Write down what Mars 4 claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Mars 4 before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Mars 4 ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Mars 4

In research: Mars 4 appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Mars 4 in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Mars 4 is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1973 in spaceflight, 1973 in the Soviet Union, 4MV, so understanding it makes those chapters shorter.
In everyday life: Look for Mars 4 outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Mars 4 in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Mars 4 means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Mars 4 out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Mars 4 in simple terms?

Why does Mars 4 matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Mars 4?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Mars 4.