12/31/2023 0 Comments Lunar rock![]() Mare basalts come in three distinct series in direct relation to their titanium content: high-Ti basalts, low-Ti basalts, and Very Low-Ti (VLT) basalts.Īlmost all lunar rocks are depleted in volatiles and are completely lacking in hydrated minerals common in Earth rocks. Regolith breccias with similar protoliths are also common. The terrae consist dominantly of mafic plutonic rocks. Moon rocks fall into two main categories: those found in the lunar highlands (terrae), and those in the maria. Greenish color generally, it appears in a rounded shape. Maroon to black the grains appear more elongated in the maria and more square in the highlands. White to transparent gray usually as elongated grains. Main article: Geology of the Moon Common lunar minerals Mineral In contrast, the oldest ages of rocks from the Earth are between 3.8 and 4.28 billion years old. ![]() Based on the age-dating technique of "crater counting," the youngest basaltic eruptions are believed to have occurred about 1.2 billion years ago, but scientists do not possess samples of these lavas. They range in age from about 3.16 billion years old for the basaltic samples derived from the lunar maria, up to about 4.44 billion years old for rocks derived from the highlands. Rocks from the Moon have been measured by radiometric dating techniques. A Moon rock known as "NWA 12691", which weighs 13.5 kilograms (30 lb), was found in the Sahara Desert at the Algerian and Mauritanian borders in January 2017, and later went on sale for $2.5 million in 2020. Some were discovered by scientific teams (such as ANSMET) searching for meteorites in Antarctica, with most of the remainder discovered by collectors in the desert regions of northern Africa and Oman. More than 370 lunar meteorites have been collected on Earth, representing more than 30 different meteorite finds (no falls), with a total mass of over 190 kilograms (420 lb). Six Apollo missions collected 2,200 samples of material weighing 381 kilograms (840 lb), processed into more than 110,000 individually cataloged samples. Moon rocks on Earth come from four sources: those collected by six United States Apollo program crewed lunar landings from 1969 to 1972 those collected by three Soviet uncrewed Luna probes in the 1970s those collected by the Chinese Lunar Exploration Program's uncrewed probes and rocks that were ejected naturally from the lunar surface before falling to Earth as lunar meteorites.
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