![]() For iron meteorites to exist, the parent bodies from where they originate are from shattered apart and no longer exist - and most have crystallized, which is a feature that is diagnostic in the identification of an iron meteorite. Iron meteorites originate from the small molten cores of these asteroids which explains why iron meteorites are far more rare. There are two types of stony meteorites: chondrites, which are those that have not experienced undue heat and pressure and possess chondrules (spherules that condensed out of the gaseous solar nebula from which our solar system was born), and achondrites, those without chondrules, which are far less common. Some even contain impact melt breccias of different rocks. Stony meteorites represent the crust and mantle of these former protoplanets, as this is the majority of an asteroid’s volume that’s why nearly 95% of all meteorites are stony. Many of these collisions were catastrophic resulting in the total shattering of many asteroids - and thus the source of the vast majority of future meteorites. In early solar system history repeated collisions between asteroids occurred it was a cosmic pinball gallery. The composition of the stone indicates that it most likely originated in the Lunar Highlands.First, there are three types of meteorites: stones, irons and stony-irons - and here’s why. The partially melted matrix is due to the high pressure of a meteorite impact on the Lunar surface, which ejected part of the surface regolith. Flecks of iron are plentiful and exist as remnants from previous iron meteorite impacts on the Moon. The present slice reveals the Night Sky Lunar meteorite's dark brecciated interior, indicating that it is composed mainly of rare Lunar regolith clasts embedded in a partially melted matrix. ![]() This fall would have lit the Saharan sky up before hurtling down to its site of discovery. Eventually, this mass intersected with the Earth's own orbit where its surface was flash-heated to 2,800 degrees Fahrenheit on entry, then rapidly cooled in the frigid temperatures of Earth's upper atmosphere, before slowing to approximately 200 miles per hour on its final descent. That initial strike had sufficient force to eject this and other rocks from the surface of the moon at escape velocity, leaving them to float freely in space. The meteorite would have started its journey to Earth as a result of a massive meteor strike on the moon's surface, likely creating one of the craters we see on the Moon today. Only the smaller 1800-gram piece has been sliced, whilst the larger 2550-gram piece has been kept fully intact as a museum specimen. It was discovered in two pieces in the Mauritanian Sahara Desert by nomads in 2020. The total known weight (TKW) of the Night Sky Lunar meteorite is only 4.35kg. The present stunning 63.14-grams slice was cut from its sister meteorite. Looking deeply into this slice is like staring into the Milky Way on a dark night. The soft edges of the large clasts are perfectly juxtaposed against the dark blue-grey matrix, which is scattered with flecks of iron. The Night Sky Lunar meteorite is unique and distinctive among Lunar meteorites. Also listed as one of the official main mass holders of this material. There are many silica grains in NWA 4734 that are about 100 m in size, and they contain small amounts of Al 2 O 3 (0.590.99 wt) and Na 2 O (0.210.26 wt. ![]() ISBN-10: 0521258723 Bill Cassidy led meteorite recovery expeditions in the Antarctic for fifteen years and his searches have resulted in the collection of thousands of meteorite specimens from the ice. Cassidy, University of Pittsburgh, 364 pages, 9 1/4 X 6 1/4, hardback. The authenticity of this specimen is guaranteed and certified by me, the Geologist J.A.Poblador, member of the Global Meteorite Association G0043 and International Meteorite Collectors Association IMCA 5681. Meteorites, Ice, and Antarctica A Personal Account. Meteoritical Bulletin Database: "NWA 13951" ![]()
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