Wandering Star Meteorites
Ivuna Meteorite
The Ivuna meteorite fell to Earth in Tanzania on December 16, 1938 as one stone weighing 705g.
Classified as a rare CI1, Ivuna is an extremely rare kind of meteorite. Its chemical make-up matches that of the sun, and it is considered to represent the raw materials from which the solar system formed.Only 9 out of the approximate 35,000 meteorites (0.03%) known to science have this solar composition.
In June 2008, the largest specimen of the Ivuna meteorite was bought by the Natural History Museum (NHM) in London from a private collector in the US. Most of the remaining material is held by private collectors or by the Tanzanian government.
CI chondrites, only a handful of which are known, are named for the Ivuna meteorite. They have very few chondrules and are composed mostly of crumbly, fine-grained material that has been changed a lot by exposure to water on the parent asteroid. As a result of this aqueous alteration, CI chondrites contain up to 20% water in addition to various minerals altered in the presence of water, such as clay-like hydrous phyllosilicates and iron oxide in the form of magnetite. They also harbor organic matter, including polycyclic aromatic hydrocarbons (PAHs) and amino acids,
They thus have the most primitive compositions of any meteorites and are often used as a standard for gauging how much chemical fractionation has been experienced by materials formed throughout the solar system.
Five CI chondrites have been observed to fall: Ivuna, Origuel, Alais, Tonk and Revelstoke. Several others have been found by Japanese field parties in Antarctica. In general, the extreme fragility of CI chondrites causes them to be highly susceptible to terrestrial weathering, and they do not survive on Earth's surface for long after they fall.
Ivuna Meteorite
