The smallest planet in the solar system. It's cold, not hot ...

A popular misconception is to consider the hottest planet as the hot Mercury, the closest planet to the Sun. In fact, the smallest planet is the cold and distant Pluto. Some deny him the status of the planet in general, but this issue is controversial, Pluto's status is not proven, and the non-planetary status is no more than a "journalistic fact". The second largest planet in size is really Mercury. The planet Pluto was named in honor of the god of the underworld of the Romans, and this name should be considered quite logical. Pluto receives much less sunlight than Earth.

The world of mystery

Powerful telescopes are available to humans only the last few decades, and the planet Pluto was officially discovered as early as the 1930s. In 1915 it was officially announced that on the outskirts of the solar system there is a ninth planet. How did you calculate this small celestial body? A body whose mass is comparable to the mass of the Moon inevitably exerts a gravitational influence on its neighbors. Observers noted that Uranus and Neptune deviate slightly from the calculated orbits, and this led to the existence of the most mysterious planet among the observed.

Under the ice

Pluto is an inhospitable planet. It is assumed that its atmosphere consists of methane gas, and the surface is covered with methane ice. There the cold reigns (the usual temperature is less than 200 degrees below zero Celsius). By the way, theoretically, he can face Neptune (their orbits are superimposed), but the probability of such an event is very small, the orbits of distant planets are too huge.

Two in one

However, the position of Pluto (as a separate planet) is ambiguous. The fact is that the smallest planet in the solar system has a huge satellite for its size. And the speed of rotation of Pluto around its axis coincides with the speed of rotation around him Charon. It seems to have frozen over one point of the planet. So if there were life on Pluto, the inhabitants of only one hemisphere would see a satellite called Charon. It is logical to even consider this pair a double planet, so large is the red satellite. Scientists believe that Charon consists of rock. But to be sure, no one can say until samples of the substance are taken from the surface.

Where does the planet come from?

As soon as Pluto was discovered, scientists began to guess where the smallest planet of the solar system came from. And the most logical was to consider the baby planet as the former satellite of Neptune. It seems that Pluto itself does not have in the composition of metallic rocks, as its satellite, but consists of ice. The secrets of its orbit have not yet been discovered by astronomers (like the secrets of some of the ice satellites of Neptune), but certain similarities are traced. But why did this happen? Perhaps Pluto was knocked down from orbit by a very large asteroid or comet. But where did Charon come from? Some believe that this is in the past part of Pluto. But this is unlikely, because the composition of the planet and the satellite is very different.

It's hard to say something for sure about the heavenly body that is so far away from us. The smallest planet of the solar system keeps its secrets. And it will be stored for a very long time, mainly because of the huge distance separating it from the Earth.

In 2006, reports appeared that Pluto is not a planet at all, but a part of the asteroid belt. But in books and studies, Pluto is the ninth planet of the solar system. Therefore, still the status of the smallest planet should have Pluto, and not Mercury.