1 gram = 0.035 ounce 1 kilogram = 2.2 pounds 1 kilometer = 0.62 mile Orgueil (France) Classic rock NWA 482 (Morocco) Carbonaceous chondrite — 11g Tatahouine (Tunisia) Abee (Alberta) Lunar achondrite — 27.7g About 20 pieces of this stone Diogenite achondrite — 37g Nakhla (Egypt) Enstatite chondrite — A buyer purchased a 1,015- With almost no metals, stone meteorites 155 grams fell May 14, 1864. It was the This witnessed fall occurred Nakhlite (martian) — 13g gram stone in Alnif, Morocco, first meteorite found to contain June 27, 1931. More than 12 This witnessed fall occurred June 28, 1911, at are the most common in space but tough Witnesses saw this meteorite in 2001. NWA 482 is the only hydrated minerals — interstellar kilograms of small, perfect 9 A.M. Searches of the strewn field pro- ⁄⁄⁄ BY MICHAEL E. BAKICH fall June 9, 1953. They found oriented lunar meteorite water. This meteorite’s internal hypersthene crystals rained to find on Earth. duced more than 40 stones, one of a stone weighing nearly 107 found, meaning its passage makeup includes high carbon out of the sky in the early which allegedly killed a dog. So far, Recovery of most stone meteorites happens because peo- kilograms in a crater 2 meters through the atmo- content, 19.5-percent total morning. None showed fusion less than a kilogram of material ple see them fall. Stones are tough to identify — they look deep and 1 meter wide. The sphere melted iron, and at least two amino crust, indicating a low-speed, Abee stone meteorite is the meteorite’s has been recovered. like Earth rocks. Meteorite hunters are hard pressed to acids: beta-alanine low-altitude unusual because it exterior, form- and glycine. fragmenta- pick out a stone meteorite on most terrain. has a high total iron ing a pattern tion. Exceptions exist, however. The ice-covered deserts content — 32.5 of flow lines. percent. of Antarctica and the vast sand dunes of northwest Shalka (India) Africa make perfect hunting grounds because of STONE METEORITES STONE Diogenite achondrite — 41.2g the lack of rock. X Many people saw one stone — nearly a meter across MAP: NASA’S EARTH OBSERVATORY/FRANCIS REDDY/ASTRONOMY: ROEN KELLY — fall November 30, 1850, in West Bengal, India. METEORITE IMAGES: ROBERT HAAG, EXCEPT WHERE NOTED Unfortunately, only 3.6 kg of the original mate- rial is preserved. This stone is 100-percent orthopyroxene. Norton County (Kansas) Millbillillie (Australia) Aubrite achondrite — 889g Eucrite achondrite — 946g This witnessed fall occurred Witnesses saw this stone mete- February 18, 1948. More than 100 Pasamonte orite fall in October 1960. The rocks were recovered, with the larg- (New Mexico) dark fusion crust hides a light inner matrix of plagio- est single specimen weighing more Eucrite achondrite — 41g than a ton. This meteorite has a lightly clase and pyroxene crystals. colored fusion crust because of its low About 75 golf-ball-size stones fell iron content. March 24, 1933, from a fireball that outshone the Sun. This meteorite’s interior has a soft ash-like texture. Calcalong Creek Pena Blanca (Australia) Springs (Texas) Lunar achondrite Aubrite achon- — 7-carat slice drite — 11.5 kg Colony (Oklahoma) Meteorite dealer Ranch workers Carbonaceous chondrite — 164g Robert Haag of Tucson, Arizona, driving a truck heard A farmer recovered a single 3.9-kg, identified this specimen as this meteorite break up in the air. highly weathered stone in 1975 lunar when it arrived in a box of The ranch’s cook saw it plunge into a from the tines of his cotton cultivator. Millbillillie stones. Chemical tests murky pond 14.6 kilometers southeast confirmed his belief. In 1980, the great meteorite hunter Harvey H. Kapoeta (Sudan) of Marathon, Texas, August 2, 1946. Nininger identified the specimen as meteoritic. The men partially drained the pond Howardite achondrite and recovered a total of 70.4 kilo- — 114g grams of this meteorite. World War II British soldiers saw this fall April 22, 1942. A single Zagami Mayo Belwa (Nigeria) 11.3-kg stone landed in front of a (Nigeria) column of armored vehicles. Shergottite Aubrite achondrite D’Orbigny — 82g Murchison Allende (Mexico) (Argentina) (martian) — (Australia) 2.35 kg Carbonaceous chondrite Angrite Witnesses reported Carbonaceous chondrite La Criolla a bright fireball and — 17 kg (Argentina) achondrite — 88g In October 1962, — 965g an 18-kg stone thunderous noise Thousands of stones fell The witnessed fall of this stone Allan Hills 84001 Residents near Murchison L6 chondrite — 6.1 kg fell near a man August 3, 1974. The on and near Allende, Mexico, occurred in 1979 near Buenos (Antarctica) witnessed this fall September After a bright fireball and many deto- herding cows. result was a single February 8, 1969, at 1:50 A.M. Analysis Aires. One 16-kg stone was Orthopyroxenite (martian) 28, 1969. Scientists consider nations, several dozen pieces of this Chemical results 4.8-kg stone with no shows a 23.8-percent iron content. Calcium recovered but was not recog- — 1.93 kilograms this meteorite important stone fell over an 8-kilometer-long match rocks test- fusion crust. and aluminum inclusions date this meteor- nized as a meteorite until some Searchers found this specimen because it contains amino region east of La Criolla, Argentina. ed by the Viking ite 100 million years older than Earth. 20 years later. in 1984. It originated in Mars’ Eos Chasma acids, the first we’ve found of The pictured stone landed in the probe on Mars. region. Some scientists thought ALH 84001 extraterrestrial origin. mayor’s yard. contains microfossils. NASA © 2012 Kalmbach Publishing Co. This material may not be reproduced in any form without permission from the publisher. www.Astronomy.com 1 gram = 0.035 ounce 1 kilogram = 2.2 pounds 1 kilometer = 0.62 mile Landes (West Virginia) Steinbach Heavy metal Ungrouped octahedrite (Germany) Cape York (Greenland) — 337g Chemically anomalous Twannberg Woodbine (Illinois) Medium octahedrite — 45g (Switzerland) Iron meteorites make up less than 10 Fine octahedrite — 471grams Meteoriticists classify this — 37 kilograms Hexahedrite to coarsest Nantan (China) meteorite as chemically A single specimen of Medium octahedrite In 1894, Admiral Robert Peary octahedrite — 38g percent of space rocks but are easy to In the spring of 1953, farmer anomalous. It contains pyrox- this meteorite, measur- identified three pieces of Cape — 1.5 kg Henry Albrecht plowed up enes and 6.3-percent nickel. ing 16 inches (40 cm) A farmer found a single identify on Earth. ⁄⁄⁄BY MICHAEL E. BAKICH York as meteorites. The larg- Chinese inhabitants wit- a 106-pound (48.2 kg) iron A single 154-pound (70 kg) across, was found in 35-pound (16 kg) piece est — a 34-ton giant called nessed this meteorite fall meteorite about a mile west specimen was found in 1930, 1724. Silicate inclusions in a barley field after he’d When most people think of a meteorite, they visualize a Ahnighito (the “Tent”) — now in 1516. The largest speci- of Woodbine, Illinois. About but it wasn’t make up two-thirds of finished plowing. Note the chunk of iron, perhaps one they’ve seen displayed at a resides in New York’s American men recovered weighs 20 percent of the meteorite is recognized its mass, and the metal large schreibersite (an iron- museum or planetarium. On Earth, iron meteorites look Museum of Natural 4,400 pounds (2,000 kg). made up of silicate inclusions. as a meteor- is 9-percent nickel. nickel mixture containing out of place in regions with no iron-bearing minerals. The metallic portion contains ite until 1968. History. phosphorus) crystals snak- Nantan contains 6.8-per- With a metal detector, you can locate iron meteorites 10.6-percent ing through the rest of the cent nickel. Most speci- nickel. nickel-iron matrix. mens are weathered and that have lain dormant for centuries. In space, stone fracture easily because IRON METEORITESIRON meteoroids (which originate in asteroids’ rocky crusts) far This iron contains 5-percent nickel. of moisture they outnumber irons, which come from asteroid cores. X absorbed. MAP: NASA’S EARTH OBSERVATORY/FRANCIS REDDY/ASTRONOMY: ROEN KELLY ALL METEORITE IMAGES: ROBERT HAAG, EXCEPT WHERE NOTED Shingle Springs Sikhote-Alin (Russia) (California) Coarsest octahedrite — 117 kg Ungrouped ataxite At 10:38 A.M. local time on February — 456g 12, 1947, witnesses saw a fireball brighter Ataxites (from the Greek for “no Canyon than the Sun. About 4 miles up, this meteorite structure) are meteorites that show Diablo fragmented and scattered over a 1-square- no Widmanstätten lines when etched. (Arizona) kilometer area. High nickel content makes these Coarse octahedrite — 1.5 kg meteorites the most rust-resistant of the irons. The Shingle Springs ataxite The world’s most famous — and contains 17-percent nickel. best preserved — impact crater lies 3 miles west of Canyon Diablo, Henbury (Australia) Arizona. The crater measures Medium octahedrite — 30 kg three-quarters of a mile (1.65 kilo- The Henbury meteorite fell meters) across and 600 feet (183 roughly 5,000 years ago in Australia’s meters) deep. Northwest Territory. Since 1931, mete- Ocotillo orite hunters have recovered hundreds (California) of fragments and located at least 13 associ- Coarse octahedrite ated craters. Henbury is 7.5-percent nickel. — 738g Odessa (Texas) Coarse octahedrite — 29 kg A meteorite hunter found a 28.6 kilogram specimen 5 miles north of The first person to recognize the Tambo Quemado (Peru) Ocotillo. The iron contains 7-percent Odessa crater as meteoritic was Medium octahedrite — 3.85 kg nickel, 0.5-percent cobalt, and tiny Daniel Barringer, who also identified A single 310-pound (141 kg) Udei Station (Nigeria) Meteor Crater’s origin. The Odessa crater amounts of other metals, including specimen was found in 1950 in Medium octahedrite — 851g 1.65 parts-per-million of gold.