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Articles in Whitish Appearance, Whereas the Ites

Articles in Whitish Appearance, Whereas the Ites

By Gregory T. Shanos with heat-altered, barely visible mateur astronomers enjoy is a 6. For example, observing objects in the an H3 is high- with universe from afar, holding well-preserved chondrules, and Anightly vigils at the telescope, an LL6 is a low-low-iron collecting ethereal photons chondrite with thermally altered exhibit a crystal pattern called a matrix. consist of with our eyes or with CCD chondrules. The ordinary H, L, Widmanstätten pattern when broken, angular fragments of cameras. Unbeknownst to many, and LL are also sliced, polished, and etched with mantle rock and -iron that there is also a way to collect sometimes called -bronzite nitric acid. show have been fused together by “rock solid” representatives of the chondrites, olivine-hypersthene thin, parallel impact. Solar System, in the form of chondrites, and amphoterites, when etched. show no All —except meteorites. Starting a respectively. Widmanstätten pattern or interior pieces of those that collection is a rewarding and appear to have Neumann lines, because of their broke apart after passing educational pursuit. The following been chondritic before being high nickel content. through the Earth’s atmo- essay is a compilation of over 30 altered by heat or impact. The Iron meteorites are subdivided sphere—exhibit fusion crust on years of experience that I have HED (, , and according to a chemical their exteriors. Fusion crust is gained in the art of collecting ) achondrites are classification system using nickel a black, melted outer coating, meteorites. confirmed to have originated from and the trace elements gallium, which is evidence of atmospheric There are three basic types of the (4) Vesta (Figure 2). germanium, and iridium to define entry (Figure 3). Meteorites are meteorites: stones, and Other classes of achondrites distinct chemical groups. These designated as falls or finds. A fall stony-irons (Figure 1). Stone include acupulcoites, , groups are named IAB, IC, IIAB, is a meteorite that was actually meteorites comprise 92 percent , , , IIC, IID, IIE, IIF, IIG, IIIAB, IIICD, seen to fall and was picked up of all known meteorites. Stones , and . These IIIE, IIIF, IVA, IVB, and immediately after impact. Falls represent the crustal surface of other classes are very rare and ungrouped irons. are the most scientifically an asteroid and are divided into best collected after some Stony-irons comprise only 2 valuable meteorites since they two broad categories: chondrites experience in the study of percent of meteorites and are are pristine, unaltered samples and achondrites. Chondrites meteorites. divided into two categories: of extraterrestrial material. contain chondrules, which are Iron meteorites comprise 6 and mesosiderites. Finds are meteorites that were small spherical bodies formed by percent of the meteorites in Stony-irons contain pieces of an not seen to fall and are usually the re-melting of mineral grains museum collections. Irons are asteroid’s “stony” silicate mantle found accidentally. Finds have in the solar nebula. Chondrites pieces of the metallic core of an and its nickel-iron core. The been “terrestrialized”— are subdivided into ordinary asteroid. Iron meteorites are origin of pallasites is controver- weathered and chemically chondrites and enstatite chon- divided into three broad catego- sial: they were once widely altered—after being on Earth for drites, and can be further ries based on their nickel content: thought to represent the core- an extended period of time. subdivided into three basic types: , hexahedrites and mantle boundary of an asteroid, Finds will exhibit weathered H (high-iron), L (low-iron), and ataxites. Hexahedrites contain but now seem more likely to fusion crust, which will not be as LL (low-low-iron). This letter the least nickel, 4.5 to 5.8 result from large impacts in the jet-black as the crust on a fall. designation is followed by a percent; octahedrites contain 4.5 early Solar System. Pallasites are Make sure the fusion crust is number, usually from 3 to 6. A to 6.5 percent nickel; and ataxites arguably the most beautiful still visible and not totally meteorite with well-defined, have the greatest nickel content, meteorites, containing gem-grade weathered away: the presence of unaltered chondrules is a 3; one 16 to 30 percent. Octahedrites olivine (peridot) in a nickel-iron fusion crust on a meteorite adds Figure 1: The three basic types of meteorites—stones, irons, and stony-irons. Left: Parnallee LL3 chondrite, which fell in the Madura district, Tamil Nadu, India, on February 28, 1857. Note the exquisite preservation of the chondrules, which were formed during the condensation of the solar nebula. Specimen is a partial slice weighting 5.5 grams and measuring 42 mm x 26 mm x 3 mm. Center: The Odessa IA coarse iron was found in 1922 in Ector County, Texas. Note the Widmanstätten pattern typical of octahedrites. Specimen is an endpiece weighing 192.9 grams and measuring 65 mm x 60 mm x 15 mm. Rght: Stony-iron pallasites consist of gem-grade peridot (olivine) in a nickel-iron matrix and are the most stunningly beautiful of all the meteorites. Pictured is the found in 1822 in the Atacama Desert, Chile. Specimen is a partial slice weighting 64.4 grams and measuring 84 mm x 58 mm x 3 mm.

16 REFLECTOR ✶ D ECEMBER 2016 The aesthetics of a meteorite is Association). The IMCA ensures also a consideration when that members are experienced purchasing a meteorite. A full meteorite dealers and sell only slice of a stone, iron, or stony- authentic meteorites. iron is preferable to a partial Ensure that the meteorite market value to the specimen. mass of the specimen to obtain slice. Does the partial slice have comes with proper documenta- Meteorites are named after the the cost per gram. For example, a a natural edge with fusion crust? I tion. An undocumented meteorite locality from which they were $50 specimen weighing 10 grams personally do not like a perfectly is almost worthless to a collector! collected. The Meteoritical costs $5 per gram. Shop around, square or rectangular sliced All you know is that it is some Society has a nomenclature since dealer prices per gram of a meteorite. This particular cut type of stone or iron. But from committee, which assigns every meteoritic specimen can vary looks very synthetic and unap- where? What is the locality? What authenticated meteorite an tremendously. Ordinary chon- pealing to me. Iron meteorites is its classification? Is it a fall or official name (Table 1). drites typically average from $1 typically exhibit regmaglypts— a find? What is the official name? Meteorites are sold as to $5 up to $10 per gram. Falls depressions that look like Proper labeling is therefore individuals, endpieces, and slices. typically cost more than finds thumbprints—on their crusts, essential. When purchasing a An individual is a complete, uncut since fallen meteorites are in which adds aesthetic appeal. meteorite look for the specimen’s meteorite. An endpiece is an more pristine condition. Irons are Regmaglypts are the result of official name, classification, fall individual that has been cut in less expensive, typically averag- ablation from atmospheric entry. or find, fusion crust present, total half or in quarters. A slice is a ing $0.10 to $0.50 up to several Dealers will charge more for a known weight, cost per gram, cross-section of an individual. dollars per gram for individuals. meteorite that is aesthetically surface area (size), rarity, and Slices can be further cut in half Slices are typically priced at $1 pleasing. Most of the time, this is overall aesthetic appeal of the or in quarters and are then or more per gram. Pallasites are well worth the money. meteorite. A detailed label will referred to as partial slices. A pricey, up to $30 per gram. Table 1 lists several websites always be provided with a thinly cut slice will have a larger Mesosiderites are more afford- that are invaluable to the meteorite sold from an IMCA surface area than a thick slice of able at $5 to $10 per gram. meteorite collector. When member. the same weight or mass, and Lunar and martian meteorites are purchasing a meteorite, the buyer Recent finds in the Sahara therefore a thin slice will give you typically priced at several should be aware of some basics. Desert in Africa have flooded the the largest size for your money. thousand dollars per gram! I The online auction site eBay is a meteorite market. This is a good The is also would stay away from the rarer good place to start. When thing, since most of these a consideration when purchasing types of meteorites when first deciding to purchase a meteorite, meteorites are rather affordable a meteorite, because the total starting out. Once a collector has make sure the dealer is a for many people. Referred to as known weight will affect a obtained the more commonly member of the IMCA (Interna- NWA (northwest Africa) followed meteorite’s price. For example, available specimens and is more tional Meteorite Collectors by a number, they have been was there only a single stone that knowledgeable in the field of fell, or many individuals? Do the , then it’s time to known individuals total only a few acquire the rarer specimens. As a pounds or kilograms, or over a collectable, meteorites appreciate ton? For example, the martian in value over time. However, meteorite Zagami fell on October conventional holdings like stocks, 3, 1962, in Nigeria. Only a single bonds, and mutual funds are stone weighing 40 pounds (18 kg) probably a much better long-term exists on the entire planet Earth! investment strategy. Allende, a rare kind of meteorite Meteorite falls, especially called a , historic falls, have the highest fell on February 8, 1969, in market value. An historic Chihuahua, specimen is a witnessed fall Mexico. Many associated with an interesting individuals story. For example, a bright have been super- visible in the sky Figure 2: Telescopic reflectance spectrum of asteroid (4) Vesta (open squares) and collected, over Russia on February 15, laboratory bidirectional reflectance spectra of ground, powdered HED (howardite, totaling over 2013, caused a series of shock eucrite, diogenite) meteorites (solid lines). The two vertical lines around 0.93 and 1.97 two tons! waves that shattered windows, micrometers indicate the centers of two major absorption bands for pyroxene in the Meteorites damaged thousands of buildings, spectra of Vesta and the laboratory spectra of HED meteorites. The Dawn mission, which orbited asteroid Vesta in 2011–2012, has confirmed these findings. The HED classes are are usually and left some 1,500 people illustrated by the Juvinas eucrite, Johnstown diogenite, and NWA 982 howardite, all sold by the injured. Fortunately, no one died from the author’s personal collection. Juvinas fell in Juvinas, Ardèche, France, on June gram. When from this incredible meteorite 15, 1821; partial slice weighing 7.3 grams and measuring 44 mm x 27 mm x 3 mm. purchasing a impact. The meteorite was named Johnstown fell in Weld County, Colorado, on July 6, 1924. Partial slice weighing 20.4 meteorite, Chelyabinsk and classified as an grams and measuring 33 mm x 33 mm x 8 mm. NWA 982 was found in Morocco-Algeria; partial slice weighing 2.0 grams and measuring 24 mm x 21 mm x 2 mm. Graph credit: take the cost LL5 with a Hiroi, T., Pieters, C.L., and Takeda, H., 1994, Grain size of the surface regolith of asteroid and divide it total known weight of over a ton 4 Vesta estimated from its reflectance spectrum in comparison with HED meteorites, by the total (Figure 3). Meteoritics & Planetary Science 29(3), 394–396.

T HE ASTRONOMICAL LEAGUE 17 formation of our Solar System. fullerenes. The diamonds are Their scientific significance also only nanometer-sized and formed adds value to a meteorite for the in the vacuum of space. The collector. For example, a special fullerenes or buckyballs occur as type of stony chondrite called a hollow C60 and C70 with carbonaceous chondrite is of entrapped extraterrestrial noble special interest to science. The gases. Allende also contains Allende CV3 carbonaceous organic , which is carbon chondrite (C stands for carbon- bonded to hydrogen, , aceous; V for Vigarano, the type and oxygen. Polyaromatic specimen of this meteorite; and hydrocarbons, essentially tar 3 indicates well-preserved and formaldehyde (embalming chondrules) fell on February 8, fluid), have been detected in this 1969, at 1:05 p.m. local time in extraordinary meteorite. Chihuahua, Mexico (Figure 4). Entrapped stardust in the form Over two tons of this rare type of of indicates that a Figure 3: The Chelyabinsk LL5 ordinary chondrite fell on February 15, 2013, in Chelyabinsk Oblast, Russia. Note the jet-black fusion crust of these individual meteorites. The price per meteorite have been recovered. nearby supernova began the gram has been steadily decreasing, so now is a good time to purchase this historically Fortunately, Allende is readily formation of our Solar System important meteorite. Note: if a better specimen comes along, go for it! The IMCA dealer I available to collectors at $15 to 4.6 billion years ago. All this in purchased these specimens from actually went to Chelyabinsk and obtained glass that was $25 dollars a gram. This is a one very aesthetically pleasing shattered by the shock wave as the meteorite entered the atmosphere. The glass fragment meteorite that should be in every meteorite! weighs 8.27 grams and measures 50 mm x 27 mm x 4 mm and was from the garden shed window of Chelyabinsk resident Denis Karpukhin. I cannot over-emphasize the importance amateur astronomer’s collection. Another must-have carbon- of documentation when it comes to collecting meteorites. The largest central individual A 10-gram thinly sliced speci- aceous chondrite is the weights 20.8 grams and measures 30 mm x 27 mm x 20 mm. men will measure an inch by an Murchison CM2 (C for carbon- collected by nomads in the LL5, and LL6). Intermediary inch (25 mm by 25 mm) or more. aceous; M for Mighei, the type desert. The NWAs first appeared types also exist, such as H4–5. Allende contains white calcium- specimen; and 2 for well- on the meteorite market in the The NWAs are a great way to fill aluminum inclusions (CAI). preserved chondrules). The early 2000s. Most lunar and in the gaps in one’s collection. For These CAIs were the first silicate fell on martian meteorites are NWAs. example, I had a difficult time materials to have formed in the September 28, 1969 in A typical meteorite enthusiast obtaining an LL4 amphoterite for solar nebula. As the name Victoria, Australia (Figure 5). is a “type” collector, meaning they my personal collection. With the implies, carbonaceous chon- Only 220 pounds (100 kg) has collect at least one meteorite discovery of the NWAs, I was then drites contain a higher propor- been collected. The findings are from each classification. For able to obtain several LL4 tion of carbon than ordinary similar to Allende with regard example, the ordinary chondrites meteorites. chondrites. The carbon in to carbon in the form of consist of 12 main types (H3, H4, Meteorites preserve valuable Allende is mostly in the form of graphite, nanodiamonds, and H5, H6, L3, L4, L5, L6, LL3, LL4, information regarding the graphite, diamond, and fullerenes. Silicon carbide has

Figure 4: The Allende CV3 carbonaceous chondrite fell on February 8, Figure 5: The Murchison CM2 carbonaceous chondrite fell on September 1969, in Chihuahua, Mexico. Note the calcium-aluminum inclusions, which 28, 1969, in Victoria, Australia. Note the chondrules, calcium-aluminum were the first silicate materials to have formed in the solar nebula. Carbon inclusions, and black phyllosilicate matrix. The matrix of Murchison contains in Allende is bonded to itself in the form of graphite, nanodiamonds, and approximately 12 percent water and contains organic carbon in the form of fullerenes. Allende also contains organic carbon and polyaromatic amino acids, fatty acids, sugars, and nucleotides. The carbon in this hydrocarbons. Silicon carbide grains suggest that a possible nearby meteorite has yielded a wealth of information regarding the possible supernova began the formation of our Solar System. All this in one origins of life on Earth. Specimen is a 20-gram wedge-shaped endpiece incredible meteorite! Complete slice weighing 32.7 grams and measuring measuring 33 mm x 29 mm x 14 mm. 57 mm x 52 mm x 4 mm.

18 REFLECTOR ✶ D ECEMBER 2016 also been detected in meteorite typically sells for Table 1: Starting a Meteorite Collection Murchison. The most incredible $150 to $300 per gram (for Internet Sources finding of the Murchison comparison, pure gold was eBay is a good start (but let the buyer beware!): www.ebay.com meteorite is that the organic selling for $43 per gram as of International Meteorite Collectors Association (IMCA): www.imca.cc Meteorite Collector: www.meteoritecollector.org carbon is in the form of August 2016). Murchison is The Meteorite Exchange: www.meteorite.com biologically important com- becoming more difficult to Meteorite Information: www.meteorite-information.com pounds, such as amino acids, obtain, so I recommend Academic Online, free meteorite magazine: www.meteorite-times.com fatty acids, sugars, and purchasing up to a gram for Meteorite Studies: www.meteoritestudies.com nucleotides. Amino acids form your collection. Fortunately, Meteoritic Society: www.lpi.usra.edu/meteor the fundamental building blocks this meteorite has a low SAO/NASA Astrophysics Data System: adsbit.harvard.edu Lunar of . Over 78 amino density (is rather light) and a Meteorites: meteorites.wustl.edu/lunar/moon_meteorites_list_alumina.htm acids have been confirmed in gram fragment will be a Martian Meteorites: www2.jpl..gov/snc/ and www.imca.cc/mars/mar- the Murchison carbonaceous tian-meteorites.htm quarter an inch (6 mm) in size Supplies chondrite, of which 13 are of or so depending on the cut. Aluminum Labels: www.meteoritelabels.com biological importance. Fatty Obtain a specimen that has Hoppe’s No. 9 lubricating oil (product number 1003): www.amazon.com acids form the basis of Eva-Dry E-333 Renewable Mini Dehumidifier: www.amazon.com fusion crust present, because Membrane boxes: www.membranebox.com membranes. Sugars provide its presence adds value to a energy for biological systems. meteorite. Murchison will cost hobby and have the financial with a Riker mount, membrane Nucleotides (adenine, guanine, you the equivalent of a high- means to invest in lunar and box, and label (Figure 6). cytosine, thymine, and ) end eyepiece or another martian real estate. Membrane boxes contain a thin form the bases of the DNA and telescopic accessory. Note that The preservation of meteorites membrane that suspends a RNA molecules. In short, the Allende and Murchison are also is an important aspect of specimen, exhibiting both sides of Murchison carbonaceous considered historic falls. collecting. The air on Earth, rich a meteoritic slice. Reserve chondrite contains many of the The year 1969 was a signifi- in oxygen and water vapor, is a membrane boxes for small, rarer fundamental building blocks cant one in the world of science. hostile environment for meteor- meteorites. I do not recommend utilized by all living organisms On February 8, 1969, the ites. The metal flakes in ordinary starting a collection of micro- on Earth. Meteorites like the Allende CV3 carbonaceous chondrites readily rust over time. mounted meteorites that fit into Murchison may have “jump- chondrite fell in Mexico; we I recommend keeping stony 39 mm x 39 mm x 18 mm started” life on Earth! Given its landed on the moon on July 21, meteorites in a plastic bag with membrane boxes. One will pay scientific significance and low 1969; and on September 28, Eva-Dry E-333 renewable mini- more per gram for the meteorite! total known weight, Murchison 1969, the Murchison CM2 dehumidifier. This keeps the For example, if you purchase a does not come cheap. This meteorite fell in Australia. humidity low and delays the small one-gram micro-specimen Sandwiched between all these inevitable rusting of sliced stony of Allende, you can pay up to $50 events was the Woodstock music meteorites. for the specimen. That is $50 per festival in New York, August 15– Iron meteorites are best gram. Typically, $50 worth of 17, 1969. Peace, man! preserved using Hoppe’s No. 9 Allende will give you 3.3 grams of The holy grail for meteorite lubricating oil (product number meteorite at $15 per gram. It is collectors have been the lunar 1003). This oil is colorless and always preferable to have the and martian meteorites. Most of odorless and will not discolor or largest specimen you can afford. these meteorites have been found gum over time. Apply the oil to an A good size to shoot for is a in the Sahara Desert and the , then place it in a meteoritic slice that fits in the Middle East. Lunar and martian plastic Ziploc bag. Double bag it palm of your hand. meteorites typically start at a to prevent leakage of the oil. In Finally, beware of meteorite- thousand or more dollars per time, the oil finds its way out, so related material being passed off gram. Fortunately, most are one must change the oil every six as an authentic meteorite—for partial slices that are sliced very to twelve months. Use the same example, tektite-meteorite, thin (less than 0.1 inch, 1 to 2 technique for stony-iron -meteorite, or shatter mm) and are therefore more pallasites and mesosiderites. The cone–meteorite. These are not affordable to the collector. Lunar oil will not harm the pallasitic meteorites themselves but Figure 6: Smaller, rarer specimens meteorites are of two basic types: olivine crystals. meteorite-related materials that are best preserved and displayed anorthositic highland Meteorites are best displayed Continued on page 27 using membrane boxes in Riker and lowland volcanic basalts. Gregory T. Shanos, Pharm.D., is a pharmacist by profession and NASA mounts that are properly labeled. Martian meteorites are referred Solar System Ambassador by passion. He is a member of the Museum This Riker mount measures 11 cm x to as SNCs (pronounced “snicks”). Astronomical Resource Society (MARS), Local Group of Deep Sky 80 cm x 20 cm. 400 is a Observers (LGDSO), and the St. Petersburg Astronomy Club (SPAC) in lunar anorthositic . The SNC stands for shergottite, Florida. Dr. Shanos became an amateur astronomer in 1985 with the white clasts are composed of the , and chassignite, after apparition of Halley’s . His passion for meteorites began a year mineral anorthosite, which is the type specimen in each of the later when Sky & Telescope advertised authentic meteorites for sale. After purchasing three iron meteorites for a total of $60, he was predominant in the lunar highlands. three classes of martian meteor- Anorthosite gives the Moon its hooked for life! Dr. Shanos has also published over 30 review articles in whitish appearance, whereas the ites. I recommend collecting Meteorite magazine regarding organic compounds in meteorites. Note: All the featured meteorites are from the author’s personal basalts comprising the maria are a these meteorites only when you collection. Photos by the author. darker gray. have a solid foundation in the

T HE ASTRONOMICAL LEAGUE 19 Collecting Meteorites/from page 19 are the direct result of meteorites hitting the Earth. Meteorite collectors typically have a side collection of these specimens. Tektites are a natural glass formed when terrestrial debris is ejected into the atmosphere during an impact. The debris cools into droplets that harden into a black, shiny glass. The most common tektites are called indochinites and occur in Southeast Asia. They are only about 610,000 years old. Moldavites are green translucent tektites found only in Czechoslova- kia. Their source has been identified as the Nördlinger Ries impact crater in Germany. Shatter cones are rare geological features that only form in the bedrock beneath meteorite impact craters. They are evidence that the rock has been subjected to shock with very high pressures from an extraterrestrial impact. An impactite is a glassy object produced by the fusion of rock and meteorite fragments by the heat developed from the impact of a meteorite on the Earth’s surface. The Ries crater contains a substantial amount of impactite. When first starting a collection, I would begin with the most reasonably priced, commonly available meteorites. These include stones such as Allende CV3, Millbillillie (eucrite), Tatahouine (diogenite), and numerous NWA meteorites (howardite); irons such as (IA), Sikhote-Alin (IIB), Canyon Diablo (IA), Odessa (IA), (IVA), and Nantan (IIICD); and stony-irons, such as , Imilac, , and Vaca Muerta. The addition of authentic meteorites to an amateur astronomer’s arsenal of equipment would be of great benefit to their understand- On August 21, 2017, at 10:16 a.m., PDT, the moon’s shadow comes ashore just south of ing of the universe. Cloudy nights could be Astoria, Oregon, races across the United States and moves out to sea near Charleston, spent contemplating, curating, and learning South Carolina, at 2:47 p.m. Do you have the equipment to safely view the eclipse and the about the wonders of these alien extraterres- ? These glasses are ideal for viewing large sunspots on the Sun’s face and partial, trials we call meteorites. Astronomical League annual, and phases of total solar eclipses throughout the continental United States. members now have the fundamental knowl- edge to begin their own collection of meteor- ites—so let’s get started! 8 Radio Astronomy Observing Program Tired of observing with just your eyes? How about looking (or listening) to the skies with an entirely different view not possible with human senses? The Radio Astronomy Observing Program has levels for observing with radio frequencies for the beginner, the initiated, and those who are exploring their capabilities in depth. Explore different methods with simple or complex equipment—it’s your choice. Ham operators find this a unique way to further enjoy their hobby. Design your own equipment, buy something off the shelf, or adapt designs from others. Any way you choose, radio astronomy can be an adventure to meteors, planets, the Sun, space weather, or even our galaxy and beyond in the radio spectrum.

T HE ASTRONOMICAL LEAGUE 27

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