Traces of some nitrogen isotopes in ferrous meteorites suggest that the Earth’s nitrogen source may have originated in addition to the regions beyond Jupiter’s orbit, from the dust of the inner protoplanetary disk.
Pre-planetary disks are plates of dense gas and interstellar dust that form around young, newborn stars and, as their name implies, are the site of planet formation. These pages are sometimes referred to as star increments; Because of the high gravity, gas and materials around the star and the inner edge of the disk fall on the surface of the young star.
These plates are full of dust, molten material, and hot gases that collide with each other to form the nuclei of pre-planets and become planets over time as more matter is absorbed.
According to current findings, the solar system’s protoplanetary disk is divided into inner and outer parts, the inner part of which is rocky and the outer part is gaseous. Scientists now claim that the sources of one of the main elements of life on Earth are both the inner and outer parts of the protoplanetary disk.
Nitrogen is a gaseous element that, like carbon, hydrogen, and oxygen, makes life on Earth possible, making up 78 percent of the Earth’s atmosphere. It makes up a number of important biological molecules, such as hemoglobin in the blood, acetylcholine in nerve fibers, and amino acids. But nitrogen is not just the element that humans need, but all life on earth needs it to grow and survive. Discovering its source reveals clues as to how inner planets formed as well as the dynamics of distant protoplanetary disks.
Scientists have always believed that the inner protoplanetary disk was much hotter than where gaseous elements such as nitrogen condensed and existed in the solid phase, since the nuclei of today’s rocky planets were joined by the dust and rocks of the previous disk. Inner planets appeared to contain no nitrogen or gaseous elements, and had to be provided with an external disk to provide them.
Recent studies show that most of the material on Earth, which contains gaseous elements such as nitrogen, came to Earth from moon-forming collisions, and now new evidence suggests that only part of the Earth’s nitrogen came from Jupiter’s orbit.
In recent years, studies of non-gaseous elements inside meteorites (especially iron meteorites that occasionally fall to Earth) have shown that the isotopic compositions of the inner and outer solar system dusts are quite different and come from different sources. But the idea of different sources was only for non-gaseous elements, and scientists needed to know if this hypothesis applied to gaseous elements as well. If so, then we can find the source of the gaseous elements of the terrestrial planets.
Iron meteorites are the remnants of the pre-planetary nuclei that did not have a chance to become a planet and were destroyed by large collisions, leaving small fragments of rock.
Following these studies, traces of a specific nitrogen isotope were found in which all the planets of the inner planets were immersed during the years of formation of the solar system. All inner disk iron meteorites contained small amounts of the nitrogen-15 isotope, while outer disk meteorites contained nitrogen-15.
Thus, it is assumed that in the first few million years of the formation of the solar system, the planet had a precursor disk of two separate sources; Nitrogen source-14 internal disk and nitrogen-15 external disk. These studies completely changed the current story and showed that from the beginning of the formation of the planets, gaseous elements were present in the inner disk (and possibly as a degradable organic matter), which means that contrary to current knowledge, the nuclei of rocky planets from The earth was not free of gaseous elements.
These findings are significant for those studying the viability of extrasolar planets, and now, at least for Earth, we know that not all of its nitrogen came from the dust beyond Jupiter, and we know that on the planets of other pre-planets, planets that The closer their stars are, the more gas they can get from their surroundings; Even if there is no exchange between gaseous and rocky planets and materials with gaseous elements do not penetrate into the inner disk.