72: Classification and Dating of Meteorites 3. Cosmochemist Greg Brennecka details meteorite classifications, emphasizing chondrites—primitive, unmelted samples representing the early molecular cloud

Classification and Dating of Meteorites 3.  Cosmochemist Greg Brennecka details meteorite classifications, emphasizing chondrites—primitive, unmelted samples representing the early molecular cloud and serving as the "baby book" of the solar system—whereas acondrites have been melted and often come from differentiated or disrupted planets. Brennecka specializes in Calcium Aluminum-rich Inclusions (CAIs) found within chondrites, which are used as a precise clock to date the solar system at 4.567 billion years old, and another stunning type is the pallasite, believed to originate from the core-mantle boundary of a planet and featuring spectacular olivine crystals in an iron matrix. Modern cosmochemistry relies on techniques like solution chemistry, where samples are dissolved in acid to precisely measure isotopes and elements. 1958