Mercury is the smallest planet in the solar system and it is also the closest one to the Sun. An year on Mercury lasts just under 88 Earth days for which the planet makes its trip around the Sun. Because of its location to the Sun, Mercury is one of the brightest planets as seen from Earth. However, it is very hard to be observed because it is being hidden by the glare of the sun. That’s why the only opportunities to observe the planet from Earth is during a little period of time before sunrise or shortly after the sunset.
The first spacecraft reached Mercury in 1974, when the USS Mariner 10 took some pictures from the planet’s surface. In the beginning of the nineties another spacecraft was sent to the planet – MESSENGER, who completed the work of the first one and made a full map of Mercury. It was found that the planet’s surface is very similar to the Moon’s, with almost no atmosphere and with lots of craters. The surface temperature of Mercury ranges from -180 degrees to 430.
It is believed that much of the planet’s mass is in its core. It is also known that it is mainly composed of iron. The tin planet’s core is explained by several theories. The main one suggests a collision with another planet which caused the damage on Mercury’s crust. Another theory says that Mercury was formed much earlier than the other planets, at a time when the temperatures emitted from the Sun were much higher, which led to the evaporation of a portion of the crust.
One of the greatest discoveries associated with Mercury is that on the planet are visible masses of frozen water. The water had been discovered when samples were taken from craters standing in constant shade from the sun. It is considered that the most likely source of the water on Mercury is a comet which collided with the planet.
Another of Mercury’s peculiarities is related to the way of the rotation of the planet to the Sun and its axis. It is believed that at some point, an observer from the planet will be able to see the sunrise, followed by a sunset and then finally another sunrise in the same day.