Kaidun is a
meteorite
A meteorite is a rock (geology), rock that originated in outer space and has fallen to the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical ...
that fell on 3 December 1980 on a
Soviet
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
military base near what is now
Al-Khuraybah
Al-Khuraybah () is a village in east-central Yemen. It is located in the Hadhramaut Governorate
Hadhramaut Governorate () is a governorate of Yemen. Lying within the large historical region of Hadhramaut, it is the country's largest governorate. ...
in
Hadhramaut
Hadhramaut ( ; ) is a geographic region in the southern part of the Arabian Peninsula which includes the Yemeni governorates of Hadhramaut, Shabwah and Mahrah, Dhofar in southwestern Oman, and Sharurah in the Najran Province of Saudi A ...
,
Yemen
Yemen, officially the Republic of Yemen, is a country in West Asia. Located in South Arabia, southern Arabia, it borders Saudi Arabia to Saudi Arabia–Yemen border, the north, Oman to Oman–Yemen border, the northeast, the south-eastern part ...
. 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
Carbonaceous chondrites or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites. The C chondrites represent only a small propo ...
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
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 symbols, such as pare ...
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
In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The ...
-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 b ...
visible in the meteorite, each of which entered the rock at different times. This suggests that the
parent body
A parent body in meteoritics is the celestial body from which originates a meteorite or a class of meteorites.
Identification
It is easiest to correlate a meteorite with a parent body when the parent body still exists. This is the case for Lun ...
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
Deimos, a Greek word for ''dread'', may refer to:
In general
* Deimos (deity), one of the sons of Ares and Aphrodite in Greek mythology
* Deimos (moon), the smaller and outermost of Mars' two natural satellites
Fictional characters
* Deimos (comi ...
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 bel ...
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
{{DEFAULTSORT:Kaidun Meteorite
Phobos (moon)
1980s in Yemen
1980 in Asia
1980 in science
Meteorites found in Yemen