Sara Russell, Natural History Museum, London
Type 1 chondrites are meteorites (and asteroids) that have experienced extensive aqueous alteration, so that the ratio of phyllosilicates to total silicates is ≥0.9. Such lithologies are rare in our meteorite collections but can be found in multiple other environments, including as xenoliths in other meteorites, micrometeorites, interplanetary dust particles and a meteorite recovered from the Moon (Bench Crater). Notably, two recent sample return missions, Hayabusa2 and OSIRIS-REx, recovered Type 1 material from asteroids Ryugu and Bennu. The talk will review the mineralogy, petrology and oxygen isotopes of known Type 1 lithologies. Type 1 material comprises a significant component of the modern extraterrestrial flux to the Earth and is likely common throughout the Solar System. Their apparent rarity underlines the bias of our meteorite collections, since these samples are highly friable, challenging to identify, and they weather away quickly in a terrestrial environment.
About the presenter
Sara Russell is a Merit Researcher in Cosmic Mineralogy and Planetary Sciences at the Natural History Museum, London. Her research interests include Solar System formation processes and the origin and early evolution of the moons of the terrestrial planets. Currently, along with other members of her research team, she is actively investigating a range of planetary science-related topics, including the origin of water in the Solar System, transport of materials within the early protoplanetary disk, and geological processes in asteroids. The Natural History Museum’s extensive meteorite collection provides a major resource for her research work. Sara is a Science Team member of NASA's OSIRIS-REx mission, a member of the JAXA's Hayabusa2 Analysis Team, and an ESA representative on the International Science Board of JAXA's MMX mission. She edited "Chondrules and the Protoplanetary Disk" published by Cambridge University Press and is extremely proud of the fact that Asteroid 5497 Sararussell was named after her.