Kaidun is a
meteorite that fell on 3 December 1980 on a
Soviet
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nation ...
military base near what is now
Al-Khuraybah in
Yemen
Yemen (; ar, ٱلْيَمَن, al-Yaman), officially the Republic of Yemen,, ) is a country in Western Asia. It is situated on the southern end of the Arabian Peninsula, and borders Saudi Arabia to the Saudi Arabia–Yemen border, north and ...
. A fireball was observed travelling from the northwest to the southeast, and a single stone weighing about was recovered from a small impact pit.
It has been suggested that Kaidun originated from the Martian moon of
Phobos, but this is disputed.
Composition
It contains a uniquely wide variety of minerals, causing debate about its origin. It is largely
carbonaceous chondrite material of type CR2, but also contains fragments of other types, such as C1, CM1, and C3. Of the nearly 60 minerals found in the meteorite, several have not been found elsewhere in nature, such as
florenskyite, which has the
chemical formula
In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbol ...
Fe Ti P.
Origin
In March 2004 it was suggested that the meteorite originated from the
Martian moon Phobos. The reason
Phobos has been suggested is the existence of two extremely rare
alkaline-rich
clasts
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks ...
visible in the meteorite, each of which entered the rock at different times. This suggests that the
parent body
In meteoritics, a parent body is the celestial body from which originates a meteorite or a class of meteorites.
Identification
The easiest way to correlate a meteorite with a parent body is when the parent body still exists. This is the case fo ...
would have been near a source of an alkaline-rich rock, which is almost wholly produced by
deep differentiation. This points to Mars and one of its moons, and Phobos is more likely than
Deimos because it is closer to Mars.
However, mineralogical and noble gas work do not tie the lithic fragments to Mars, as they have other proven Martian meteorites, and this hypothesized link is tenuous at best.
In support of the Phobos hypothesis, in 2017 two scientists at the Western University found that meteorites originating from Phobos (and even Deimos) can travel to Earth.
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 ...
References
External links
Kaidun: A Meteorite with Everything but the Kitchen Sink written by Linda M. V. Martel, Hawai‘i Institute of Geophysics and Planetology
Phobos (moon)
1980s in Yemen
1980 in Asia
1980 in science
Meteorites found in Yemen
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