Mercury is thought to have been formed about 4.5 billion years ago when gravity combined rotating gas and dust to form a small planet. Its small size, but at the same time a huge core is the result of a collision with another giant object that "removed" most of the surface.
Mercury was observed by astronomers of Ancient Assyria before our era, believing that this planet is the messenger of the gods to Earth. Lifeless, harsh and tiny, but very curious. In evidence, we offer 10 of the most interesting facts about the planet Mercury for children - unusual discoveries of scientists.
10. The first planet in density in the solar system after the Earth
Apart from the Earth, Mercury is the second most densely planet. Despite its small size, Mercury is very dense, because it consists mainly of heavy metals and rocks, which is the main characteristic of terrestrial planets.
It is believed that if the effects of gravitational compression were taken into account both on Mercury and on Earth, then Mercury would take first place in density, which also indicates that its core is huge and rich in iron.
9. Does not have natural satellites
Mercury has no known satellites, although many objects have much less.. It is believed that the moons are formed at the same time as their parent planets, and in the case of Mercury all the materials around it were consumed by the planet, and almost nothing was left so that a satellite could form.
Another theory suggests that Mercury could not have a moon due to its proximity to the sun. Because of this, the great gravitational force of the Sun will overcome the strength of Mercury and attract any objects around it. In general, the proximity of the planet to the sun does not allow it to have a satellite.
8. Life is impossible on Mercury
For a long time, it was believed that Mercury, the planet closest to the Sun, is a glowing, dried world containing only an iron core surrounded by a thin silicate crust. Sean Solomon, director of Lamont-Doherty Earth Observatory at Columbia University, lecturer Edwin Olday, and chief researcher at NASA's MESSENGER mission, challenged this prospect in a lecture in February 2015 at Jackson School, which presented the results of the MESSENGER study.
Solomon said that instead of the dull iron world, MESSENGER showed that the surface of Mercury contains volatile elements, as well as traces of carbon and frozen water that were delivered by comets. These are discoveries that prove that the planet cannot be called absolutely “dead”, but these findings also suggest that living organisms will never be found here.
7. Time goes different
Mercury rotates around the Sun very quickly, but rotates around its axis very, very slowly. One day on Mercury (from sunrise to sunrise) is longer than one year on Mercury (one orbit around the Sun), however paradoxical it may sound. A year on Mercury takes 87.97 Earth days.
6. The core is about 80% of the mass of the planet
Mercury is an earth planet with three main layers: core, mantle and crust. Mercury's crust does not have tectonic plates, and its the iron core is huge, accounting for 85% of the radius of the planet, while the inner and outer core of the Earth make up about 55%.
Due to its unusual size, the core affects the overall size of Mercury, causing it to shrink. The iron core slowly cools and shrinks over 4.5 billion years.
5. Sudden temperature changes
Another reason why living here could not be that a person, but even a bacterium. Since Mercury is the closest planet to the Sun, the surface temperature is extreme and varies from day to night. Before sunrise, the temperature is “only” -170 ° C, and by noon rises to about 400 ° C.
The change in temperature on Mercury is due to its rotation and lack of atmosphere. During the day, the temperature is so high that it can melt some metals, and it gets very cold at night, because without the atmosphere the daytime heat cannot be held.
4. A large number of craters on the surface
The surface of Mercury, very similar to the Moon, is covered with many impact craters from comets or meteorites. Interestingly, many of these craters are named after famous late artists and writers. Craters also indicate that the planet has been geologically inactive for billions of years.
It is believed that Mercury was heavily bombarded by comets and asteroids during and shortly after its formation 4.6 billion years ago, as well as during a possibly separate subsequent event, called the Late Heavy Bombing, which ended 3.8 billion years ago.
, During this bombing, the entire surface of Mercury suffered even more due to the lack of an atmosphere that would slow down the strikes. It is believed that Mercury was volcanically active during this period.
Pools, such as the Plain of Heat, were filled with magma, forming a smooth area similar to that found on the Moon. The largest known crater is the Heat Valley, 1,550 km in diameter. Only about 15 craters have been identified on Mercury, and their exact number remains to be determined.
3. The eruptions of "geysers"
The Messenger probe, launched to study Mercury in 2004, reached the planet in 2011 and one of its first discoveries was unusual surface formations that scientists have identified as hydrogen geysers.
When Mercury was just forming, a huge amount of hydrogen concentrated in the molten iron, and later (including now), when the planet cools down slowly, this hydrogen finds a way out in the form of geysers.
2. Mercury was known in antiquity
Since Mercury can be seen without a telescope, many ancient civilizations saw the planet, and therefore it is impossible to determine who discovered it first. Nevertheless, it was first discovered with a telescope at the beginning of the 17th century by Galileo Galilei. The raw telescope of Galileo was unable to capture the phases of Mercury, this will be noticed later by the astronomer Giovanni Zupi in 1639, and thus he discovered that the planet had the same phases as on Venus and the Moon.
One of the earliest known recorded observations of Mercury is clay tablets from the library of Assyria. It is believed that these observations were made by ancient Assyrian astronomers around the 14th century BC. The name used in these entries translates as “jumping planet”.
Some Babylonian records date back to the 1st millennium BC. They named the planet Naboo after the messenger of the gods in their mythology. The ancient Greeks knew the planet as Hermes, while the Romans called it Mercury, and it remained so to this day. In ancient times, Mercury was studied as two different objects in the sky: the Grieving Star and the Evening Star.
1. The smallest planet closest to the Sun
Mercury - the closest planet to the Sun, at a distance of 57.91 million kilometers or 0.4 a.u. From the Sun to Mercury, 3.2 minutes of sunlight is required.
Mercury has a radius of 2,439 km and a diameter of 4,879 km, which is approximately equal to the size of the continental United States (quite a bit more). It has a mass of about 3.285 × 10 ^ 23 kg or about 5.5% of the mass of the Earth.