Mercury can often be seen in the morning or evening hours - at this time it seems to be a bright star in the twilight sky. In ancient times, they even believed that these were two different stars - the peoples who then inhabited the Earth gave these "stars" two names - Horus and Light, Roginea and Buddha, Hermes and Apollo.
General information
Mercury is the closest planet to the star of the solar system. It is the smallest of the entire "family", but has a very high density. Almost 80% of the entire mass of the object falls on the core. The diameter of Mercury is almost 5 thousand kilometers.
Mercury rotates faster than other planets. This happens so that it does not leave its orbit. The year of Mercury is only 88 Earth days. At the same time, the planet rotates around itself only one and a half times during this time. Thus, a Mercury day is equal to 59 Earth days. From sunrise to sunset, 179 Earth days pass.
Despite the fact that the planet is quite bright, and the diameter of Mercury allows it to be visible from Earth, we do not see it so often. This happens because Mercury is too close to the Sun. See him like thisis possible only at the time when it moves away from the star at the maximum distance.
The diameter of Mercury is slightly larger than the Moon, but its density is much higher. It is possible that the density of the center is 8900 kilograms per cubic meter. This suggests that the core consists of iron. Moreover, in this case, the core, which has a radius of 1800 km, is ¾ of the radius of the planet.
Actually, it is the diameter of Mercury that allows some scientists since the 19th century to assert that this planet was previously a satellite of Venus, which was lost as a result of a catastrophe. It is possible that this catastrophe was a collision with another planet, as a result of which Mercury not only ended up in its current orbit, but also received many of the damages seen today in the images of the planet.
Surface
Seeing the surface of Mercury became possible in 1974, when a passing Mariner 10 sent photos. It turned out that the surface of the red planet is very similar to our moon. The "earth" of Mercury is dotted with rocks and craters, including those in the form of divergent rays. These craters were formed from collisions with many meteorites. The rocks arose at a time when the core of the planet was shrinking, pulling together the crust as well.
Because Mercury is a planet, it cannot emit light. We observe it as a star only because the surface of the planet has a good reflectivity - the reflected light is visible from the EarthSun.
Atmosphere
Some signs suggest that Mercury has an atmosphere. But it is much more - a thousand times - discharged than the earthly one. It does not allow to keep warm or protect the planet from excessive heating. That is why there is a huge difference between day and night temperatures on the planet.
The almost conditional atmosphere of Mercury consists of helium, hydrogen, carbon dioxide, neon and argon, oxygen. Proximity to the luminary suggests the influence of the solar wind on the planet. This increases the likelihood of the planet developing an electric field twice as strong as Earth's, and at the same time much more stable.
Temperature
Given the almost complete absence of the planet's atmosphere, the surface heats up during the day and cools down significantly at night. The hemisphere turned towards the Sun heats up to 440 degrees Celsius. At the same time, the night hemisphere, unable to retain heat without an atmosphere, cools down to -180 degrees.
Diameter
The diameter of Mercury is 4878 kilometers. This is almost 2.5 times smaller than our planet, but 1.5 times larger than the Moon. For a long time it was believed that the diameter of Mercury in kilometers does not change. However, recent studies and data transmitted by the spacecraft indicate that its size is changeable. The new data made it possible for astrophysicists to find out that the last 4 billion years have made adjustments to the volumes of the planet. The diameter of the planet Mercury during this time decreased by 14 kilometers. The outer shell of the planet is justonly one plate, unlike the Earth, where the surface consists of several plates.
As a result of cooling and subsequent contraction of the crust, the diameter of the planet Mercury was significantly reduced. Moreover, this decrease is much more significant than under the same conditions occurs on the Moon or Mars. The data transmitted by the Messenger spacecraft make it possible to study the evolution of the planet. Perhaps soon we are waiting for new sensations.
Forecasts
Of course, no one can give an exact scenario for the future. The only realistic assumption is that as the planet cools further, the diameter of Mercury may decrease further.
However, there is also a version according to which in the distant future the planets of our system will collide. Mercury will either fall into the Sun or crash into Venus. This, however, will not happen until billions of years from now.
Scientists from France have created a model of the behavior of the solar system in the next 5 billion years. Based on the available data, it is concluded that in 3.5 billion years the orbits of the planets will intersect, provoking a collision. In such a model, almost all planets can approach the Earth at a dangerous distance, except for Mercury, which is most likely to fall into the Sun.
But still, most scientists admit that the probability of such a future is only 1%. This model only shows that it is, in principle, possible. In addition, 3.5 billion years is a fairly significant time, and at that time, humanity is likely to beit doesn’t matter what and what will collide.
