Large satellites, the size of which is related to the size of the planets about the same, the correlation between
the size of the Moon and the Earth, can be a rocky one in ten of the world. Such a group of scientists presented the findings in an article in Icarus. Short of the portal writes BBC News.
The relative size of the moon (size relative to "their" planet — Earth) far exceeds the relative size of the other moons in the solar system — its diameter is more than a quarter the diameter of Earth. Until now, scientists thought that such a large and massive satellites are rare in space.
The creators of the work decided to check this point, analyzing the probability of formation of such massive moons. It is believed that the Earth's moon was the result of a collision of the planet with the object the size of Mars around 4.57 billion years ago, so the researchers developed a computer model that estimates the probability of large-scale cosmic collisions.
According to scientists, the chances of the formation in the planetary system of the planet, whose mass is at least half of the earth, which has a satellite with a mass of at least half of the mass of the moon, are 1 in 12. Given the uncertainty created by authors' model, the odds range from 1 to 4 to 1 to 45.
Recently, another group of scientists made the discovery, forcing some to revise the existing hypotheses to explain the origin of the Moon. The researchers found that in samples of lunar soil contains much more water than previously thought, and most of the models that describe the Earth's collision with the rocks of the Moon object, suggest that most of the water had evaporated.