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Meteorite Hunting
Meteorite hunting is the search for meteorites. A person engaged in the search for meteorites is known as a meteorite hunter. Meteorite hunters may be amateurs who search on the weekends and after work, or professionals who recover meteorites for a living. Both frequently use tools such as metal detectors or magnets to discover the meteorites. Searching If the meteorite is of the iron or stony iron variety a magnet (usually mounted at the end of a stick) will pick it up from the soil surface or a metal detector will often detect it through many inches of soil. Stony meteorites —which make up the large majority of meteorites that fall— may not have a high enough nickel iron content to set off a metal detector. Large and very sensitive metal detectors may be used as well as ground-penetrating radar, lidar, and even landmine detectors. Although meteorites fall uniformly across the globe they do not typically remain on the surface in areas with a large amount of yearly rain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sublimation (phase Transition)
Sublimation is the Phase transition, transition of a substance directly from the solid to the gas state, without passing through the liquid state. The verb form of sublimation is ''sublime'', or less preferably, ''sublimate''. ''Sublimate'' also refers to the product obtained by sublimation. The point at which sublimation occurs rapidly (for further details, see #False correspondence with vaporization, below) is called critical sublimation point, or simply sublimation point. Notable examples include sublimation of dry ice at room temperature and atmospheric pressure, and that of solid iodine with heating. The reverse process of sublimation is deposition (phase transition), ''deposition'' (also called ''desublimation''), in which a substance passes directly from a gas to a solid phase, without passing through the liquid state. Technically, all solids may sublime, though most sublime at extremely low rates that are hardly detectable under usual conditions. At standard condi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Meteoritics
This is a glossary of terms used in meteoritics, the science of meteorites. # * 2 Pallas – an asteroid from the asteroid belt and one of the likely parent bodies of the CR meteorites. * 4 Vesta – second-largest asteroid in the asteroid belt and likely source of the HED meteorites. * 221 Eos – an asteroid from the asteroid belt and one of the likely parent bodies of the CO meteorites. * 289 Nenetta – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * 3103 Eger – an asteroid from the asteroid belt and one of the likely parent bodies of the aubrites. * 3819 Robinson – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * IAB meteorite, IA meteorite – an iron meteorite group now part of the IAB group/complex. * IAB meteorite – an iron meteorite and primitive achondrite of the IAB group/complex. * IAB meteorite, IB meteorite – an iron meteorite group now part of the IAB group/complex. * IC me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite Men
''Meteorite Men'' is a documentary film, documentary reality television, reality television series featuring meteorite hunters Geoffrey Notkin, Geoff Notkin and Steve Arnold. The pilot episode premiered on May 10, 2009. The full first season began on January 20, 2010, on the Science Channel. The second season premiered November 2, 2010, and season three began November 28, 2011. Professors and scientists at prominent universities including UCLA, ASU, UA, Edmonton, and other institutions, including NASA's Johnson Space Center, are featured. Summary The show follows two meteorite hunters, Steve Arnold and Geoffrey Notkin, as they travel around the world scouring the Earth's surface for meteorites. Arnold's background lies primarily in business, while Geoffrey Notkin, Notkin is a passionate collector and science writer. In the pilot episode of ''Meteorite Men'', Notkin and Arnold travel to the farmlands of Brenham, Kansas, where Arnold located and recovered the largest oriented pallas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chelyabinsk Meteor
The Chelyabinsk meteor () was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately , near-Earth asteroid that entered the atmosphere at a shallow 18‐degree angle with a speed relative to Earth of . The light from the meteor was briefly brighter than the Sun, visible as far as away. It was observed in a wide area of the region and in neighbouring republics. Some eyewitnesses also reported feeling intense heat from the fireball. The object exploded in a meteor air burst over Chelyabinsk Oblast, at a height of about . The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to , and many surviving small fragmentary meteorites. Most of the object's energy was absorbed by the atmosphere, creating a large shock wave. The asteroid had a total kinetic energy before atmospheric impact equivalent to the blast yield of , est ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminal Velocity
Terminal velocity is the maximum speed attainable by an object as it falls through a fluid (air is the most common example). It is reached when the sum of the drag force (''Fd'') and the buoyancy is equal to the downward force of gravity (''FG'') acting on the object. Since the net force on the object is zero, the object has zero acceleration. For objects falling through air at normal pressure, the buoyant force is usually dismissed and not taken into account, as its effects are negligible. As the speed of an object increases, so does the drag force acting on it, which also depends on the substance it is passing through (for example air or water). At some speed, the drag or force of resistance will be equal to the gravitational pull on the object. At this point the object stops accelerating and continues falling at a constant speed called the terminal velocity (also called settling velocity). An object moving downward faster than the terminal velocity (for example because it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteor Air Burst
A meteor air burst is a type of air burst in which a meteoroid explodes after entering a planetary body's atmosphere. This fate leads them to be called fireballs or bolides, with the brightest air bursts known as superbolides. Such meteoroids were originally asteroids and comets of a few to several tens of meters in diameter. This separates them from the much smaller and far more common " shooting stars", that usually burn up quickly upon atmospheric entry. The most powerful meteor air burst in the modern era was the 1908 Tunguska event. During this event a stony meteoroid about in size exploded at an altitude of over a sparsely populated forest in Siberia. The resulting shock wave flattened an estimated 80 million trees over a area, and may have killed 3 people. Extremely bright fireballs traveling across the sky are often witnessed from a distance, such as the 1947 Sikhote-Alin meteor and the 2013 Chelyabinsk meteor, both over Russia. If the bolide is large enough ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allan Hills
The Allan Hills () are a group of hills, mainly ice free and about long, lying just north-west of the Coombs Hills near the heads of Mawson Glacier and Mackay Glacier in the Oates Land and Victoria Land regions of Antarctica. Exploration and naming The Allan Hills were mapped by the New Zealand party (1957–58) of the Commonwealth Trans-Antarctic Expedition and named for Professor Robin Allan, R. S. Allan of the University of Canterbury, New Zealand. Allan Hills is referred to as the ''Allan Nunatak'', and mapped north of Carapace Nunatak, in the memoirs of the Scott Base Leader Adrian Hayter. Both names are in the USGS listing. Location Allan Hills lie to the north of Odell Glacier, facing Coombs Hills to the south of the glacier. They are west of the Convoy Range, south of Battlements Nunatak and east of the Antarctic Plateau. Allan Hills are in the shape of the letter "Y", with the open end pointing roughly northwards, and encompassing the Shimmering Icefield. The southern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allan Hills 84001
Allan Hills 84001 (ALH84001) is a fragment of a Martian meteorite that was found in the Allan Hills in Antarctica on December 27, 1984, by a team of American meteorite hunters from the ANSMET project. Like other members of the shergottite– nakhlite– chassignite (SNC) group of meteorites, ALH84001 is thought to have originated on Mars. However, it does not fit into any of the previously discovered SNC groups. Its mass upon discovery was . In 1996, a group of scientists found features in the likeness of microscopic fossils of bacteria in the meteorite, suggesting that these organisms also originated on Mars. The claims immediately made headlines worldwide, culminating in U.S. president Bill Clinton giving a speech about the potential discovery. These claims were controversial from the beginning, and much of the scientific community ultimately rejected the hypothesis once all the unusual features in the meteorite had been explained without requiring life to be present. Despit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discover (magazine)
''Discover'' is an American general audience science magazine launched in October 1980 by Time Inc. It is currently owned by LabX Media Group. History Founding ''Discover'' was created primarily through the efforts of ''Time'' magazine editor Leon Jaroff. He noticed that magazine sales jumped every time the cover featured a science topic. Jaroff interpreted this as a considerable public interest in science, and in 1971, he began agitating for the creation of a science-oriented magazine. This was difficult, as a former colleague noted, because "Selling science to people who graduated to be managers was very difficult".Hevesi, Dennis"Leon Jaroff, Editor at Time and Discover Magazines, Dies at 85" ''The New York Times'', 21 October 2012 Jaroff's persistence finally paid off, and ''Discover'' magazine published its first edition in 1980. ''Discover'' was originally launched into a burgeoning market for science magazines aimed at educated non-professionals, intended to be eas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mary Roach
Mary Roach (born March 20, 1959) is an American author specializing in popular science and humor. She has published seven New York Times bestsellers: '' Stiff: The Curious Lives of Human Cadavers'' (2003), '' Spook: Science Tackles the Afterlife'' (2005), '' Bonk: The Curious Coupling of Science and Sex'' (2008), '' Packing for Mars: The Curious Science of Life in the Void'' (2010), '' Gulp: Adventures on the Alimentary Canal'' (2013), '' Grunt: The Curious Science of Humans at War'' (2016), and '' Fuzz: When Nature Breaks the Law'' (2021). Early life and education Mary Roach was born in Hanover, New Hampshire Her family moved to Etna, a village within the town of Hanover, and Roach attended Hanover High School and received a bachelor's degree in psychology from Wesleyan University in 1981. Career After college, Roach moved to San Francisco, California, and spent a few years working as a freelance copy editor. Her writing career began in the public affairs office of the San F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
