What is the diameter of Mars and how does it relate to the diameter of the Earth? Diameter, mass and description of Mars

The fourth planet of the Solar System Mars is the scene of many fantastic stories. Writers and directors often place here extraterrestrial civilizations, hostile or friendly to us. Studies, however, show that such a highly developed life on Mars is not exactly. This does not mean that the Red Planet is a boring and uninteresting place. On the contrary, very many scientists in their thoughts are carried away here, trying to understand the secrets and explain the features of the fourth planet. Parameters such as the diameter of Mars, its mass, acceleration of gravity, the first and second cosmic velocities on the planet, and so on, are carefully collected and analyzed throughout the study period of our neighbor. Let's get to know him better.

Features of the orbit

Mars - a description of the planet, perhaps, it is worth starting with this - the distance from the Sun follows immediately behind the Earth. Its orbit has a length of almost 1.5 billion kilometers and, like most planets, is an ellipse. Behind the orbit of Mars is the main belt of asteroids.

One revolution around the star of the Red Planet takes much longer than the Earth - 687 days. The average distance of Mars to the Sun is about 228 million kilometers. For comparison, the same indicator for the Earth is 149.5 million km.

Similarities

There are also close in their values the parameters that characterize the Earth and Mars. The description of the planet always contains information about the period of rotation around the axis. As you know, for the Earth it's about 24 hours. In the case of the Red Planet, the figure is not much different - 24 h 37 min 22.7 s. Because of this rapid rotation, our neighbor has a somewhat flattened form from the poles. As a result, the diameter of Mars at the equator is somewhat different from that for the poles. However, the same feature is peculiar to the Earth. The diameter of Mars in kilometers around the equator is 6739.8. This is approximately 53% of the analogous parameter of our planet. The diameter of Mars, if measured in the region of the poles, will be less by 42 km. This parameter is in the same relationship with the terrestrial as the previous one.

The axis of the Red Planet has a rather large angle of inclination to the plane of the orbit (24 ° 56 '), which provides Mars with another similarity to the Earth - the presence of a change of seasons. However, due to other features of the planet, the differences between the summer and winter periods are much sharper here.

Some other physical parameters

In general, the main characteristics of the Earth looks more impressive than Mars. The planet's mass is 6.4185 × 10 ²³ kg - it's just 0.107 from the analogous parameter of the Earth.

The density of the substance that makes up Mars is 6.4185 × 10 ²³ kg. The magnitude of the acceleration of gravity is 3.7 m / s ² . The temperature conditions on the Red Planet are very different from terrestrial. At the equator in the summer time, the air can warm up to + 30º, and cool to -80º on a winter night. In the region of the poles, the temperature sometimes drops to -143º.

Surface

The planet Mars, whose photo is delivered by almost all the apparatus, whose course lies past the Red Planet, is characterized by rather interesting features of the surface relief. Here you can find a huge number of craters and traces of ancient and atmospheric and water activity.

The main feature of the surface is its division into two zones. The southern hemisphere resembles the lunar landscape. In general, the surface here rises by one or two kilometers above the average level. The northern part of the planet, on the contrary, is below the average level. There are few craters here, most of the space is occupied by more or less smooth plains, presumably formed as a result of erosion and flooding with lava. The wrong and wide border separating the two zones passes through a large circle tilted about 30 ° to the equator. The reason for this division of the surface of the scientist is still unclear.

Composition

The planet of the solar system Mars enters the same group of cosmic objects as the Earth. These are the so-called planets of the terrestrial group. They are characterized by a stony structure unlike gas giants, in which gaseous substances dominate. Leading among other elements in the composition of Mars is silicon (21%), followed by iron, magnesium, calcium and aluminum (12.7, 5, 4 and 3%, respectively). In addition, the Red Planet is quite high in comparison with the Earth level of sulfur - 3.1% of the total composition.

Planet Mars, whose photo is difficult to confuse with pictures of other objects, has, as you know, a reddish shade of the surface. This effect is provided by oxides and hydrates of iron, which are part of the soil of the planet along with the silicates that make up its basis.

At the poles

Polar caps of the Red Planet have a thickness of almost four kilometers. They consist of water ice and carbon dioxide. The latter, under the conditions of low temperatures prevailing here, condenses out of the atmosphere. In the area of the southern polar cap were found geysers, which are a mixture of carbon dioxide with dust and ice, emitted to a considerable height above the surface.

The polar caps begin to melt in the spring. As a result, the atmospheric pressure rises noticeably and very strong winds arise that facilitate the movement of massive gas masses in the opposite hemisphere. The wind speed sometimes reaches 100 m / s.

These movements also cause dust storms, which are a characteristic feature of the planet. Dust storms make a significant contribution to the formation of conditions on Mars: they affect the temperature change, lead to soil erosion.

Traces of water

One of the motivations that compel people to learn space is the desire to find if not a developed life, then at least conditions suitable for its emergence. Mars has long been considered as one of the worthy candidates for this role. The data accumulated to date show that on the Red Planet, once upon a time there could be one of the main conditions for the emergence of life - water in a liquid state. On Mars, erosion is found, reminiscent of its characteristics of water. Surface images transmitted by rovers allowed scientists to see even the alleged channels of parched rivers. In addition, the apparatuses found on the Red Planet minerals, for the formation of which positive temperatures and a water-alkaline environment are necessary. However, scientists have not yet reached the final conclusions about the water past of Mars.

Atmosphere

Water vapor is present in the air envelope of the planet, but in small amounts - 0.1%. In general (95%), the atmosphere of the planet consists of carbon dioxide, also here there are nitrogen (2.7%), argon (1.6%) and oxygen (0.13%). In the atmosphere, methane and heavy inert gases were also detected in an even smaller concentration than the above substances.

Methane is considered one of the mysteries of Mars. This substance decomposes under the influence of sunlight, and for its accumulation in the atmosphere, even in such a small amount, a constant source of replenishment is needed. To date, there are two main candidates for this role: gas hydrates, heated by internal heat, and Martian bacteria, presumably existing in the deep layers of the lithosphere.

Highscores

Despite the fact that the diameter of Mars (in km), its mass and other parameters are inferior to the terrestrial, there are also objects that amaze with their dimensions. The main ones are volcanoes and mountains. The vast volcanic plain of Tarsis is located in the northern hemisphere of the planet and extends for two thousand kilometers. Here are located such volcanoes as Arsia, Pavonis and Ascreus. Next to them, on the edge of Tarsis, is the main "attraction" of the Red Planet - Mount Olympus. Reaching a height of 27 km, it is considered the highest in the entire solar system. The diameter of the surface occupied by Olympus is 550 km.

On the territory of Tarsis, one can also find faults. The largest of them is the so-called Mariner Valley: 4.5 thousand kilometers in length and 600 km in width at a depth of 10 km. On the slopes of the valley, there are often the most impressive landslides in the solar system.

A magnetic field

If the diameter of the planet Mars and its other numerical characteristics are accurately known and not subject to doubt, then some other parameters cause scientists a lot of questions. Among them is the magnetic field of the planet. In fact, it does not exist: nothing protects Mars from the effects of sunlight. However, studies of space vehicles have shown that the planet has zones with a sufficiently strong magnetic field. There is a version that Mars, about 4 billion years ago, possessed powerful protection against sunlight, similar to the terrestrial, but then lost it.

The fixed remnants of the field are bands with variable polarity, stretching from west to east. Their width reaches thousands of kilometers. Such local magnetic fields are a mystery to scientists. It is not clear either their origin or the reason for such polarity.

The diameter of Mars, however, also some time ago was a mystery to people. Studies of the Red Planet are continuing and are becoming more profound due to the improved technique and new knowledge in the field of astrophysics. Therefore, there is every reason to suppose that the mysteries of Mars will somehow be uncovered and explained in the not so distant future.