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Hraschina Meteorite
Hraschina is the official name of an iron meteorite that fell in 1751 near the Hrašćina village in Hrvatsko Zagorje, Croatia. This meteorite is important because it was the first fall of an iron meteorite viewed and reported by a significant number of witnesses, despite its low remaining total known weight. The Hraschina meteorite also proved that rocks really can "fall from the skies". History On 26 May 1751, at 18:00, a fireball was seen over Hrašćina and sounds like detonations were heard as far away as Varaždin, giving an estimate of nearly of area over which the meteorite's sound was audible. Many people taking their Sunday evening walk witnessed the event. Baltazar Adam Krčelić, a clergyman, historian, and a noted chronicler of daily events, who was spending time in the village of Biškupec, recorded the following: :"In Biškupec near Varaždin an unusual phenomenon like a small cloud was seen — although it was not a cloud — which became paler and paler, prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octahedrite
Octahedrites are the most common structural class of iron meteorites. The structures occur because the meteoric iron has a certain nickel concentration that leads to the exsolution of kamacite out of taenite while cooling. Structure Octahedrites derive their name from the crystal structure paralleling an octahedron. Opposite faces are parallel so, although an octahedron has 8 faces, there are only 4 sets of kamacite plates. Due to a long cooling time in the interior of the parent asteroids, these alloys have crystallized into intermixed millimeter-sized bands (from about 0.2 mm to 5 cm). When polished and acid etched the classic Widmanstätten patterns of intersecting lines of lamellar kamacite, are visible. In gaps between the kamacite and taenite lamellae, a fine-grained mixture called plessite is often found. An iron nickel phosphide, schreibersite, is present in most nickel-iron meteorites, as well as an iron-nickel-cobalt carbide, cohenite. Graphite and troili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naturhistorisches Museum Wien
The Natural History Museum Vienna (german: Naturhistorisches Museum Wien) is a large natural history museum located in Vienna, Austria. It is one of the most important natural history museums worldwide. The NHM Vienna is one of the largest museums and non-university research institutions in Austria and an important center of excellence for all matters relating to natural sciences. The museum's 39 exhibition rooms cover 8,460 square meters and present more than 100,000 objects. It is home to 30 million objects available to more than 60 scientists and numerous guest researchers who carry out basic research in a wide range of topics related to human sciences, earth sciences, and life sciences. The '' Index Herbariorum'' code assigned to this museum is W and it is used when citing housed herbarium specimens. History The history of the Natural History Museum Vienna is shaped by the passion for collecting of renowned monarchs, the endless thirst for knowledge of famous scientists, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium
Gallium is a chemical element with the symbol Ga and atomic number 31. Discovered by French chemist Paul-Émile Lecoq de Boisbaudran in 1875, Gallium is in group 13 of the periodic table and is similar to the other metals of the group (aluminium, indium, and thallium). Elemental gallium is a soft, silvery metal in standard temperature and pressure. In its liquid state, it becomes silvery white. If too much force is applied, the gallium may fracture conchoidally. Since its discovery in 1875, gallium has widely been used to make alloys with low melting points. It is also used in semiconductors, as a dopant in semiconductor substrates. The melting point of gallium is used as a temperature reference point. Gallium alloys are used in thermometers as a non-toxic and environmentally friendly alternative to mercury, and can withstand higher temperatures than mercury. An even lower melting point of , well below the freezing point of water, is claimed for the alloy galinstan (62– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid in the carbon group that is chemically similar to its group neighbors silicon and tin. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the discovery of the elements. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. In 1886, Clemens Winkler at Freiberg University found the new element, along with silver and sulfur, in the mineral argyrodite. Winkler named the element after his country, Germany. Germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classified as an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hraschina Meteorite, Natural History Museum, London , official name of a meteorite fallen in 1751 in Croatia near Hrašćina.
{{Disambig ...
Hraschina may refer to: * Hrašćina, a municipality in the Krapina-Zagorje County in Croatia. * Hraschina meteorite Hraschina is the official name of an iron meteorite that fell in 1751 near the Hrašćina village in Hrvatsko Zagorje, Croatia. This meteorite is important because it was the first fall of an iron meteorite viewed and reported by a significant n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Franz Anton Ritter Von Schreibers
Carl Franz Anton Ritter von Schreibers (15 August 1775 – 21 May 1852) was an Austrian naturalist who was a native of Pressburg, Hungary, Habsburg Empire (today Bratislava, Slovakia). In 1847, an uncommon iron-nickel-phosphide ((Fe,Ni)3P) mineral was named in his honor by Wilhelm Karl Ritter von Haidinger (1775–1871). The mineral is found in meteorites, and is known today as schreibersite. As a zoologist, he was the first to perform a comprehensive anatomical study of the olm, a cave-dwelling, aquatic amphibian. The plant genus ''Schreibersia'' (synonym '' Augusta'', family Rubiaceae) was named in his honor by Johann Baptist Emanuel Pohl. Biography He earned his medical doctorate from Vienna in 1798, but also studied botany, mineralogy and zoology at the university. For a brief period of time he assisted his uncle, Joseph Ludwig von Schreibers, with his medical practice in Vienna. As a young man, he also toured museums throughout Europe. In 1802 he was an assistant of natural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Society
The Geological Society of London, known commonly as the Geological Society, is a learned society based in the United Kingdom. It is the oldest national geological society in the world and the largest in Europe with more than 12,000 Fellows. Fellows are entitled to the postnominal FGS (Fellow of the Geological Society), over 2,000 of whom are Chartered Geologists (CGeol). The Society is a Registered Charity, No. 210161. It is also a member of the Science Council, and is licensed to award Chartered Scientist to qualifying members. The mission of the society is: "Making geologists acquainted with each other, stimulating their zeal, inducing them to adopt one nomenclature, facilitating the communication of new facts and ascertaining what is known in their science and what remains to be discovered". History The Society was founded on 13 November 1807 at the Freemasons' Tavern, Great Queen Street, in the Covent Garden district of London. It was partly the outcome of a previous club ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Widmanstätten Pattern
Widmanstätten patterns, also known as Thomson structures, are figures of long nickel–iron crystals, found in the octahedrite iron meteorites and some pallasites. They consist of a fine interleaving of kamacite and taenite bands or ribbons called ''lamellae''. Commonly, in gaps between the lamellae, a fine-grained mixture of kamacite and taenite called plessite can be found. Widmanstätten patterns describe features in modern steels, titanium, and zirconium alloys. Discovery In 1808, these figures were observed by Count Alois von Beckh Widmanstätten, the director of the Imperial Porcelain works in Vienna. While flame heating iron meteorites, Widmanstätten noticed color and luster zone differentiation as the various iron alloys oxidized at different rates. He did not publish his findings, claiming them only via oral communication with his colleagues. The discovery was acknowledged by Carl von Schreibers, director of the Vienna Mineral and Zoology Cabinet, who named the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Count Alois Von Beckh Widmanstätten
Count (feminine: countess) is a historical title of nobility in certain European countries, varying in relative status, generally of middling rank in the hierarchy of nobility. Pine, L. G. ''Titles: How the King Became His Majesty''. New York: Barnes & Noble, 1992. p. 73. . The etymologically related English term "county" denoted the territories associated with the countship. Definition The word ''count'' came into English from the French ''comte'', itself from Latin ''comes''—in its accusative ''comitem''—meaning “companion”, and later “companion of the emperor, delegate of the emperor”. The adjective form of the word is "comital". The British and Irish equivalent is an earl (whose wife is a "countess", for lack of an English term). In the late Roman Empire, the Latin title ''comes'' denoted the high rank of various courtiers and provincial officials, either military or administrative: before Anthemius became emperor in the West in 467, he was a military ''comes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Baptiste Biot
Jean-Baptiste Biot (; ; 21 April 1774 – 3 February 1862) was a French physicist, astronomer, and mathematician who co-discovered the Biot–Savart law of magnetostatics with Félix Savart, established the reality of meteorites, made an early balloon flight, and studied the polarization of light. The biot (a CGS unit of electrical current), the mineral biotite, and Cape Biot in eastern Greenland were named in his honour. Biography Jean-Baptiste Biot was born in Paris on 21 April 1774 the son of Joseph Biot, a treasury official. He was educated at Lyceum Louis-le-Grand and École Polytechnique in 1794. Biot served in the artillery before he was appointed professor of mathematics at Beauvais in 1797. He later went on to become a professor of physics at the Collège de France around 1800, and three years later was elected as a member of the French Academy of Sciences. In July 1804, Biot joined Joseph Louis Gay-Lussac for the first scientific hot-air balloon ride to measur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
