A lunar meteorite is a meteorite that is known to have originated on the Moon. A meteorite hitting the Moon is normally classified as a transient lunar phenomenon.
Transfer to Earth
Most lunar meteorites are launched from the Moon by impacts making lunar craters of a few kilometers in diameter or less.[6] No source crater of lunar meteorites has been positively identified, although there is speculation that the highly anomalous lunar meteorite Sayh al Uhaymir 169 derives from the Lalande impact crater on the lunar nearside.
Cosmic-ray exposure history established with noble-gas measurements have shown that all lunar meteorites were ejected from the Moon in the past 20 million years. Most left the Moon in the past 100,000 years. After leaving the Moon, most lunar meteoroids go into orbit around Earth and eventually succumb to Earth's gravity. Some meteoroids ejected from the Moon get launched into orbits around the Sun. These meteoroids remain in space longer, but eventually intersect the Earth's orbit and land.[9]
Lahmada 020 Basic information
Name: Lahmada 020 This is an OFFICIAL meteorite name.
Abbreviation:There is no official abbreviation for this meteorite.
Observed fall:No
Year found:2018
Country:Western Sahara
Mass:12.17 kg
Classification history:Recommended: Lunar (feldsp. breccia)
This is 1 of 182 approved meteorites classified as Lunar (feldsp. breccia).
Search for other: Lunar meteorites
Comments:Approved 9 Feb 2019 Writeup
Writeup from MB 108: Lahmada 020 27.411°N, 9.845°W Saguia el Hamra, Western Sahara Find: 2018 Nov Classification: Lunar meteorite (feldspathic breccia) History: Found at a location north of Jdiriya, Morocco, near Oued Skikima, in November 2018. Material was obtained by Ahmad Bouragaa and Aziz Habibi, and some was purchased by Mark Lyon and Mendy Ouzillou in November 2018. Physical characteristics: Multiple pieces (total 12.168 kg) of the same distinctive very fine grained, dark gray microvesicular material with sparse, irregularly distributed small milky clasts. Petrography: (A. Irving and S. Kuehner, UWS) Sparse, very small mineral class of anorthite, olivine, pigeonite and augite occur within a dominant extremely fine grained, microvesicular matrix containing accessory kamacite, troilite and minor barite. Geochemistry: Olivine (Fa34.0-35.8, FeO/MnO = 86-94, N = 2), pigeonite (Fs22.7-28.6Wo8.2-8.8, FeO/MnO = 49-59, N = 2), augite (Fs17.1-17.4Wo38.5-36.6, FeO/MnO = 51-54, N = 2), anorthite (An95.8-96.9Wo0.4-0.2, N = 2). Classification: Lunar (feldspathic regolith melt breccia). Specimens: 20.62 g including a polished slice and one polished thin section at UWB; remainder with A. Bouragaa, A. Habibi, M. Lyon and M. Ouzillou.
Data from:
MB108
Table 0
Line 0:
State/Prov/County:Saguia el HamraPlace of purchase:AgadirDate:2018 NovLatitude:27.411°NLongitude:9.845°WMass (g):12168Pieces:severalClass:Lunar (feldsp. breccia)Shock stage:highWeathering grade:lowFayalite (mol%):34.9-35.8Ferrosilite (mol%):22.7-28.6; 17.1-17.4Wollastonite (mol%):8.2-8.8; 38.5-36.5Classifier:A. Irving and S. Kuehner, UWSType spec mass (g):20.62Type spec location:UWBMain mass:A. Bouragaa/A. Habibi/M. Lyon/M. OuzillouComments:Work names AB18-69, Lyon18-1; submitted by A. Irving
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