#Cosmochemistry
The chemistry of the Solar System, read from the minerals, elements and isotopes in meteorites.
Cosmochemistry is the chemistry of the Solar System and beyond. Meteorites are its main source of evidence: real material from asteroids, the Moon and Mars that can be weighed, cut and analysed in a laboratory.
The rarest chondrites, called CI chondrites, have almost exactly the same mix of elements as the Sun, apart from the lightest gases. That makes them a reference recipe for the whole Solar System.
Ratios of isotopes, which are versions of the same element with different masses, act as fingerprints that show where a meteorite came from. Radioactive isotopes act as clocks, measured with methods such as uranium–lead, rubidium–strontium and samarium–neodymium dating.
Part of Meteorites across the sciences.
Lessons (1)
- Carbonaceous chondritesCarbonaceous chondrites are rare, often dark and crumbly, and scientifically priceless.
Courses (2)
- Chondrites and the birth of the Solar SystemChondrites are the least changed rocks we have. Their components formed in the disc around the young Sun and date the start of the Solar Sys
- The molecules of life from spaceSome meteorites contain amino acids, the building blocks of proteins, made without any living thing.
Famous meteorites (1)
- OrgueilA crumbly black meteorite from 1864 whose chemistry is the closest match on Earth to the Sun itself.
Meteorite types (1)
- CI chondritesThe chemically most primitive rocks known: their make-up matches the Sun's. CI chondrites, named after Ivuna in Tanzania, match the comp
Space missions (1)
- Hayabusa2Pieces of a carbon-rich asteroid that turned out to be the purest primitive rock ever studied. Hayabusa2 reached the asteroid Ryugu in June
Meteorite minerals (6)
- DolomiteA calcium magnesium carbonate common in CI chondrites and in the Ryugu and Bennu samples.
- EpsomiteEpsom salt, a magnesium sulphate that crystallises on CI chondrites in collections. Epsomite is magnesium sulphate with seven water molecule
- FerrihydriteA poorly crystalline iron oxyhydroxide found in the matrix of CI chondrites. Ferrihydrite is a hydrous iron oxide with very small, poorly or
- GypsumA calcium sulphate found in white veins in CI chondrites, partly grown after they reached Earth. Gypsum is a soft, water-bearing sulphate of
- SaponiteA swelling clay mineral intergrown with serpentine in CI chondrites and in samples from Ryugu and Bennu.
- SerpentineA water-bearing sheet silicate that makes up much of the matrix of CM and CI chondrites.
Glossary (7)
Questions and answers (1)
- Why do CI chondrites match the composition of the Sun?CI chondrites formed from material that never melted or lost most of its elements, so apart from gases, their chemistry closely matches the
People (1)
- Edward AndersThe Chicago cosmochemist whose table of Solar System element abundances became a standard, and whose team first found stardust older than th
Museums and collections (1)
- National Museum of Natural History, ParisFrance's national collection, rich in historic French falls such as L'Aigle, Chassigny and Orgueil.