Meteorite Northwest Africa 12264 May Change Everything Known About Planet Formation, Research Suggests
Theories regarding the formation of the solar system could be in for a major revisit due to a recent discovery associated with a meteorite labeled Northwest Africa 12264. The findings related to this meteorite could change the known trajectory of the Solar System, as explained in the journal Communications Earth & Environment. Further examinations under a scanning electron microscope revealed that the meteorite came from the outer Solar System. However, its age did not align with what was expected out of an object from outer space, as per past assertions. It implies the age range of planetary bodies in the outer solar system may not be as initially assumed.
Northwest Africa 12264
Northwest Africa 12264 was first detected at its namesake location in 2018, according to IFL Science. The exact site where it was found has been kept under wraps by experts, but it somehow made its way into the custody of an independent researcher in Agadir, Morocco. The independent researcher allowed other experts to examine the 1.8-ounce meteorite, which led to many interesting insights regarding the processes involved in the creation of the solar system.
Challenging Past Assertions
Findings from the investigation of Northwest Africa 12264 questioned the past assertion, which claimed that planets near the sun formed earlier than far away from the star in the solar system, as reported by Phys. In this assertion, the planets beyond the asteroid belt, between Mars and Jupiter, were considered to be farther. The latest theories suggest that planets formed due to protoplanetary disks assimilating together. This process of coming together is called accretion. After this step, the acquired material starts heating up, which differentiates the planet into distinct layers called the core, mantle, and crust. Both steps were believed to have occurred at different points in time, for the outer and inner planets of the solar system.
In the case of inner protoplanets, the formation was deemed to have occurred 4.566 billion years ago, while for the outer protoplanets it was thought to have happened 4.563 billion years ago. Researchers believed that outer protoplanets formed later because they supposedly consisted of more water and ice compared to their inner counterparts. A greater presence of these constituents implies that it would have taken more time for its inner core to melt down due to heat. The readings from Northwest Africa 12264 oppose this belief and suggest that both 'near' and 'far' protoplanets formed at the same time.
Investigation of Northwest Africa 12264
Initially, researchers determined the region from which Northwest Africa 12264 arrived by understanding the ratio of chromium and oxygen present in it. The ratio suggested that it came from a planetary body beyond the asteroid belt. The analysis of the rock's lead isotopes showed that the meteorite was around 4.564 billion years old. It is closer to the age associated with inner protoplanets. It implies that rocky planets both outside and inside the asteroid belt were forming in a concurrent manner. The findings support assertions made by experts from the examination of exoprotoplanetary disks, which suggest that planetesimals were being formed rapidly, across radial distances in the galaxy.
Planetesimals are essentially solid constituents formed in the initial steps of planet formation. These constituents forming rapidly farther away from the sun means planets were also being created at a fast pace. This difference of two or three million years in the formation of planetary bodies beyond the asteroid belt is crucial. This time difference could impact the theories about planet formation in the solar system. Researchers are stunned by the findings, but want to wait before regarding them as conclusions, as they are yet to be fully confident following their aging determination process.