With a detailed analysis of Earth and meteor samples, scientists were able to track the sequence of events that led to the appearance of Earth and Mars.
Planets grow in the process of accretion - the gradual build-up of additional material in which they collide with neighboring objects. It is characterized by randomness with the loss and acquisition of material.
Massive planetary bodies at speeds of several km / s crash into others. This leads to an increase in temperature and the creation of magmatic oceans. By the time of formation of the Martian size, the planets are endowed with weak gravity, which is not enough to hold a dense atmospheric layer. The blows do not stop, because of what the planets change.
Now scientists think that something similar happened to Earth and Mars. The findings were based on measurements of magnesium isotopic compositions. This ratio changed due to the loss of silicate vapor. As a result, more than 40% of the Earth’s mass disappeared in the process of formation. For analysis, samples were taken from the Earth, the Red Planet and the asteroid West. Used a new technique to obtain more accurate measurements of isotopic ratios.
Main conclusions:
- Samples are endowed with distinct ratios of magnesium isotopes.
- Heavy isotopic compositions result in significant (40%) weight loss after repeated evaporation processes during the accretion period.
- This leads to other chemical changes during the growth period.
It has now become clear that the loss of steam in the collision of high-energy planetary accretion greatly affects the planetary composition.
