Sayh al Uhaymir 169 (SaU 169) is a 206 grams
lunar meteorite found in the Sayh al Uhaymir region of the
Sultanate of Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of t ...
in January 2002.
This stone is an
impact-melt breccia
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix.
The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of ...
with exceedingly high concentrations of
thorium
Thorium is a weakly radioactive metallic chemical element with the symbol Th and atomic number 90. Thorium is silvery and tarnishes black when it is exposed to air, forming thorium dioxide; it is moderately soft and malleable and has a high ...
and other
incompatible element In petrology and geochemistry, an incompatible element is one that is unsuitable in size and/or charge to the cation sites of the minerals of which it is included. It is defined by the partition coefficient between rock-forming minerals and melt b ...
s;
phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...
,
rare-earth element
The rare-earth elements (REE), also called the rare-earth metals or (in context) rare-earth oxides or sometimes the lanthanides ( yttrium and scandium are usually included as rare earths), are a set of 17 nearly-indistinguishable lustrous silv ...
s, and the three most important naturally occurring
radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consi ...
elements,
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...
, thorium, and
uranium
Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...
have been segregated in the liquid phase when the lunar
mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...
s
crystallized. The impact that eventually sent this stone to the Earth is dated at 3.9 billion years and could be the
Imbrium impact. It collided with the Earth less than 9,700 years ago.
It is complete, a light gray-greenish rounded stone, dimensions and mass , found on January 16, 2002, in the central desert of Oman at 20° 34.391' N and 57° 19.400' E.
According to geologist
Edwin Gnos and coworkers, the meteorite's origin can be pinpointed to the vicinity of the
Lalande impact crater; isotopic analysis shows a complex history of four distinct lunar impacts:
"Crystallization of the impact melt occurred at 3909 ± 13 Ma, followed by exhumation by a second impact at 2800 Ma, which raised the sample to a regolith position at unconstrained depth. A third impact at 200 Ma moved the material closer to the lunar surface, where it mixed with solar-wind–containing regolith. It was launched into space by a fourth impact at <0.34 Ma".
[Gnos, Edwin, et al., 2004]
Pinpointing the Source of a Lunar Meteorite: Implications for the Evolution of the Moon
Science
Science is a systematic endeavor that Scientific method, builds and organizes knowledge in the form of Testability, testable explanations and predictions about the universe.
Science may be as old as the human species, and some of the earli ...
30 July 2004: Vol. 305 no. 5684 pp. 657–659. .
See also
*
Glossary of meteoritics
This is a glossary of terms used in meteoritics, the science of meteorites.
#
* 2 Pallas – an asteroid from the asteroid belt and one of the likely parent bodies of the CR meteorites.
* 4 Vesta – second-largest asteroid in the asteroid b ...
*
List of lunar meteorites
External links
*https://archive.today/20030604170334/http://epsc.wustl.edu/admin/resources/meteorites/sau169.html
*http://illite.unibe.ch/sau169/
*http://www.ilexikon.com/Sayh_al_Uhaymir_169.html
*http://www.zeit.de/2004/33/3_Fragen
References
{{Meteorites by name
Meteorites found in Oman
Lunar meteorites
2002 in Oman
2002 in science
January 2002 events in Asia