The history of the solar system still continues to amaze scientists.
Before the appearance of full-fledged planets, planetesimals were present in the solar system - small objects formed due to the coalescence of even smaller cosmic bodies. They subsequently transformed into protoplanets. Scientists concluded that most of the meteorites that hit the Earth were planetesimal debris. This is reported by Science Alert.
According to researchers, most planetesimals either completely melted in the early stages of the solar system's history, or survived as a "pile of stones." However, one family of meteorites stands out from the rest - apparently, the celestial stones belonged to one planetesimal, which was also a molten heap of stones.
The accepted meteorite classification system assumes that any single parent body cannot be a source of both molten (chondritic) and non-molten (achondritic) meteorites. This stems from an understanding of how planetesimals are formed.
Models show that they form almost instantaneously, which prevents them from melting. For a long time, it was hypothesized that planetesimals can be both molten regions and consisting of whole stones, but it was extremely difficult to obtain evidence. However, a group of American researchers seems to have succeeded.
Experts believe that the variety of planetesimals was much wider. The body, the fragments of which fell on the Earth, should have contained fused and whole layers of rocks. In addition, it had a liquid metal core, which created a powerful electromagnetic field. The study authors believe that this will serve as an incentive to seek more evidence for the existence of complex planetary structures. This will help understand how planetesimals formed at the dawn of the solar system.