4/25/2023 0 Comments Chondrite meteoriteAnother indication of their age is the fact that the abundance of non- volatile elements in chondrites is similar to that found in the atmosphere of the Sun and other stars in our galaxy. Dating using 206Pb/ 204Pb gives an estimated age of 4,566.6 ± 1.0 Ma, matching ages for other chronometers. These asteroid parent bodies of chondrites are (or were) small to medium-sized asteroids that were never part of any body large enough to undergo melting and planetary differentiation. An instance of the latter occurred in the Holbrook fall of 1912, in which an estimated 14,000 stones grounded in northern Arizona.Ĭhondrites were formed by the accretion of particles of dust and grit present in the primitive Solar System which gave rise to asteroids over 4.54 billion years ago. Chondrite falls range from single stones to extraordinary showers consisting of thousands of individual stones. The largest individual stone ever recovered, weighing 1770 kg, was part of the Jilin meteorite shower of 1976. There are currently over 27,000 chondrites in the world's collections. Other non-metallic meteorites, achondrites, which lack chondrules, were formed more recently. Ĭhondrites can be differentiated from iron meteorites due to their low iron and nickel content. One of their characteristics is the presence of chondrules (from the Ancient Greek χόνδρος chondros, grain), which are round grains formed as molten, or partially molten droplets, in the space by distinct minerals, that normally constitute between 20% and 80% of a chondrite by volume. Their study provides important clues for understanding the origin and age of the Solar System, the synthesis of organic compounds, the origin of life and the presence of water on Earth. ![]() Estimates for their contribution to the total meteorite population vary between 85.7% and 86.2%. ![]() Some such bodies that are captured in the planet's gravity well become the most common type of meteorite by (whether quickly, or after many orbits) arriving on a trajectory toward the planet's surface. They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids. Small to medium asteroids that were never part of a body large enough to undergo melting and planetary differentiation.Ī chondrite / ˈ k ɒ n d r aɪ t/ is a stony (non- metallic) meteorite that has not been modified, by either melting or differentiation of the parent body. A specimen of the NWA 869 chondrite (type L4–6), showing chondrules and metal flakes
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |