astro.wikisort.org - Meteorite

The Yamato 691 (abbreviated Y-691) is the 4.5 billion year old chondrite meteorite discovered by members of the Japanese Antarctic Research Expedition[3] on the blue ice field of the Queen Fabiola Mountains (Yamato Mountains) in Antarctica, on December 21, 1969.[2]

Yamato 691
Type	Chondrite
Class	Enstatite chondrite
Composition	Pl(An32-75), En99.2Wo-0.3, tro., nini., oldh., perr., schr., metal(2.2-2.5%Ni, 0.16-0.22%Co)[1]
Country	Antarctica
Region	Queen Fabiola Mountains (Yamato Mountains)
Coordinates	71°50′S 36°15′E[2]
Observed fall	No
Fall date	4.5 billion years ago
Found date	December 21, 1969
TKW	715 grams (1.576 lb)

History

Yamato 691 was one among 9 meteorite specimens identified by the Japanese Expedition Team in 1969. It was later studied at the Max Planck Institute for Chemistry, Mainz, Germany.[4]

In April 2011, NASA and co-researchers from the United States, South Korea and Japan have found a new mineral named "Wassonite" in Yamato 691.[5]

Composition and classification

This meteorite is a stony enstatite chondrite. Minerals reported from the meteorite include:[6]

• Troilite
• Spinel
• Augite
• Diopside
• Enstatite
• Pigeonite
• Albite
• Nepheline
• Iron
• Olivine
• Wassonite - discovered in April, 2011

See also

• Glossary of meteoritics

References

External links

• Mindat.org
• Petrochemical study of the Yamato-691 enstatite chondrite (EH3) II: Descriptions and mineral compositions of unusual silicate-inclusions (1988)
• Trace element composition and distribution of Yamato-691, an unequilibrated enstatite chondrites (1988)

На других языках

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- [en] Yamato 691

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[ru] Ямато 691

Ямато 691 (англ. Yamato 691) — метеорит, обнаружен в 1969 году в Антарктике.

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