Oxygen isotopes in meteorites trace early Solar System organics

Harvard researchers analyzed carbonaceous chondrite meteorites using three oxygen isotopes and found that their organic matter retains pristine signatures from the birth of the Solar System. The isotope marks stayed largely unchanged for 4.5 billion years, suggesting the molecules formed in the cold outer protoplanetary disk.

• Organic matter in the meteorites matches the Carbonaceous Chondrite Anhydrous Mineral (CCAM) line
• Isotope signatures were minimally altered by parent-body processes
• Samples included CI, CM and CR groups plus Bells and Tarda
• Organics formed 4.5 billion years ago in the outer disk