Scientists from the University of Copenhagen offered a new explanation for why the planets in the solar system differ in composition. In their work, they studied the calcium-isotopic composition of some meteorites, the Earth and Mars.
Most of the planetary researchers agree that the planets in our system have a similar origin. It all starts with small fragments revolving around the sun. Then they collide, merge and create large protoplanets. But then it becomes unclear why the ready-made options differ.
The new theory reports that the protoplanets grew at the same rate, but stopped at different times. Those that were smaller, stopped growing before large ones. Scientists believe that in the remaining time, the material continued to flow to the protoplanetary disk, increasing the objects. They also believe that at the beginning of the process, the composition of the material was different from what was added later. Because of this, the rocky worlds are different. For the study also used the asteroid Vesta. Calcium isotopes are involved in rock formation and provide clues about the origin. Scientists have found that isotope ratios in samples correlate with the masses of parent planets and asteroids. It turns out that the smaller ones simply stopped accreting the material, while the larger ones continued to add, but it was different from the previous one.