Traces of volcanic activity in photographs of Mercury have forced scientists to change their minds about its origin. According to the new theory, the mini-planet migrated into the solar system from the outside.

Mercury, the restless god of trade, probably lives up to his name given by humans to the smallest planet in the solar system. Traces of volcanic eruptions were found on its surface, which refute the most popular theories of the origin of Mercury.
Similar volcanic eruptions on Earth occur when hot lava heats up water and volatile compounds, which are then ejected from the bowels of the planet.
Mercury, however, is much closer to the Sun, so such compounds must have evaporated from the infernal temperatures prevailing on the surface 4.5 billion years ago, at the birth of the planet
The images taken by the automatic interplanetary station "Messenger" in 2008 clearly show deposits of volcanic ash. Until now, scientists have assumed that volcanic eruptions occurred immediately after the emergence of the planet.
However, a careful analysis of the photographs revealed that the craters of the Mercury volcanoes formed at different periods of time, from 3.5 to 1 billion years, that is, much later than the time of the birth of Mercury.

A snapshot of a section of the surface of Mercury, obtained by the AMS "Messenger". In the lower right corner - a part of the Sveinsd? Ttir crater with a darkening Beagle ledge
© NASA / Johns Hopkins University Applied Physics Laboratory / Carnegie Institution of Washington
This discovery made it possible to put forward a theory of the formation of Mercury outside the solar system. According to scientists, the mini-planet has become a neighbor of Earth and Mars by cosmic standards relatively recently.
The discovery of volcanic activity on Mercury also conflicts with another well-known theory, according to which this planet at one time experienced a collision with a larger object that destroyed most of its crust.
After all, if the crust of Mercury was destroyed, it would not have left such long-standing traces of volcanic activity.
Scientists admit that the mini-planet poses questions about its origin, which are currently impossible to answer.