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.
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. [1]
Although meteorites fall uniformly across the globe they do not typically remain on the surface in areas with a large amount of yearly rainfall. If a newly fallen meteorite is not recovered within a few months it is likely to be buried with alluvium or covered by plant growth. Some arctic and desert regions have proven to be well-suited to preserving meteorites, and can provide excellent surfaces for hunting visually.
Meteorites can be very valuable to scientists studying planetary science and to collectors. Individual stones may weigh mere grams or hundreds of kilograms. Their values vary widely based on rarity and composition, as well as the conditions in which they are found.
In the United States, most state laws state that a meteorite find belongs to the landowner of the land upon which the meteorite was found. [2] This doctrine contrasts with the once-predominant rule in state courts on the finding of treasure trove, where buried gold or silver coinage (or paper money representing the same) is deemed to belong to the finder.
Many state courts have interpreted their laws as granting the state sole title to any meteorite recovered on state-owned lands.
United States laws and enforcement of laws regarding recovery of meteorites on federally owned public lands is unsettled. With respect to large meteorites, the federal government has asserted title to all such meteorites if proven to be found on federal land, because: [3]
This policy derives from cases as far back as 1944, when the federal government supposedly seized the Drum Mountain Meteorite in Utah from a group of interned Japanese-American U. S. citizens. In reality, the meteorite was purchased for $700 by the US National Museum (NMNH). [4] The federal government has sometimes agreed to negotiate a small finders fee for large meteorites, as with the interned Japanese-Americans, but has never agreed to pay anything resembling full market value of the meteorite to the discoverer.
In the case of small meteorites, ownership of meteorites found on federal land is not covered in the Code of Federal Regulations, and in the past hobbyists have been able to remove small quantities of rock for non-commercial use. [5] However, in recent years the U.S. Bureau of Land Management (BLM) has asserted that it owns all meteorites recovered on BLM land, apparently arguing that BLM stands in the same position as a private landowner under state law. [6] The BLM further asserts that under the 1906 Antiquities Act, all meteorites on BLM land belong to the Smithsonian Institution. [7] A BLM memorandum of September 10, 2012, reaffirms that meteorites found on public land belong to the Federal Government. [8] Permits can be acquired for systematic search for meteorites on public land undertaken for scientific, educational, or commercial purposes; casual, limited meteorite hunting does not require a permit.
Antarctic prospecting is very expensive and therefore can only be carried on by well funded organizations. Approximately half of the meteorites found in Antarctica have been recovered by ANSMET (Antarctic Search for Meteorite program). The ANSMET program is a major source of the extraterrestrial material that is available for scientific investigation. Japanese finds make up the majority of the remainder, and China has recently begun exploration. [9]
A popular geological feature employed by Antarctic meteorite hunters is an area where a natural downsloped plain meets an uprising ridge, such as where the East Antarctic Ice Sheet, creeping to the sea at about three metres (10 feet) per year, meets the Transantarctic Mountains. The downslope-mountain ridge combination allows the creeping gravity-driven icesheet to start rising sharply upwards. As it does so, the exposed snow and ice are removed by fierce winds and sublimation, effectively harvesting the embedded meteorites and leaving them to lie on the surface along the length of the mountain ridge. [10]
The famed 1.93 kilograms (4.3 lb) Allan Hills 84001 meteorite, commonly abbreviated as ALH 84001 and believed to be from Mars, [11] was found at Allan Hills, Antarctica in 1984. In 1996 NASA scientists announced that it might contain evidence for microscopic fossils of Martian bacteria based on the carbonate globules it contained. [12]
In the aftermath of a meteor air burst, a large number of small meteorites can fall to the ground, generally at terminal velocity, such as occurred with the 2013 Chelyabinsk meteor. [13] When that occurs local residents and schoolchildren will often seek to locate and pick up the fragments due to their potential value. In the case of the Chelyabinsk meteor, many were located in snowdrifts by following a visible hole that had been left in the outer surface of the snow. [13]
Meteorite Men is a U.S. television series following two atypical meteorite hunters.
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a fireball, also known as a shooting star; astronomers call the brightest examples "bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater.
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. As of September 2020, 277 meteorites had been classified as Martian, less than half a percent of the 72,000 meteorites that have been classified. The largest complete, uncut Martian meteorite, Taoudenni 002, was recovered in Mali in early 2021. It weighs 14.5 kilograms and is on display at the Maine Mineral & Gem Museum.
A metal detector is an instrument that detects the nearby presence of metal. Metal detectors are useful for finding metal objects on the surface, underground, and under water. The unit itself consists of a control box, and an adjustable shaft, which holds a pickup coil, which can vary in shape and size. If the pickup coil comes near a piece of metal, the control box will register its presence by a changing tone, a flashing light, and or by a needle moving on an indicator. Usually the device gives some indication of distance; the closer the metal is, the higher the tone in the earphone or the higher the needle goes. Another common type are stationary "walk through" metal detectors used at access points in prisons, courthouses, airports and psychiatric hospitals to detect concealed metal weapons on a person's body.
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 1.93 kilograms (4.3 lb).
A lunar meteorite is a meteorite that is known to have originated on the Moon. A meteorite hitting the Moon is normally classified as a transient lunar phenomenon.
The Morasko meteorite nature reserve is located in Morasko, on the northern edge of the city of Poznań, Poland. It contains seven meteor craters. The reserve has an area of 55 hectares and was established in 1976.
A micrometeorite is a micrometeoroid that has survived entry through the Earth's atmosphere. Usually found on Earth's surface, micrometeorites differ from meteorites in that they are smaller in size, more abundant, and different in composition. The IAU officially defines meteoroids as 30 micrometers to 1 meter; micrometeorites are the small end of the range (~submillimeter). They are a subset of cosmic dust, which also includes the smaller interplanetary dust particles (IDPs).
ANSMET is a program funded by the Office of Polar Programs of the National Science Foundation that looks for meteorites in the Transantarctic Mountains. This geographical area serves as a collection point for meteorites that have originally fallen on the extensive high-altitude ice fields throughout Antarctica. Such meteorites are quickly covered by subsequent snowfall and begin a centuries-long journey traveling "downhill" across the Antarctic continent while embedded in a vast sheet of flowing ice. Portions of such flowing ice can be halted by natural barriers such as the Transantarctic Mountains. Subsequent wind erosion of the motionless ice brings trapped meteorites back to the surface once more where they may be collected. This process concentrates meteorites in a few specific areas to much higher concentrations than they are normally found everywhere else. The contrast of the dark meteorites against the white snow, and lack of terrestrial rocks on the ice, makes such meteorites relatively easy to find. However, the vast majority of such ice-embedded meteorites eventually slide undiscovered into the ocean.
The pallasites are a class of stony–iron meteorite. They are relatively rare, and can be distinguished by the presence of large olivine crystal inclusions in the ferro-nickel matrix.
Treasure hunting is the physical search for treasure. For example, treasure hunters try to find sunken shipwrecks and retrieve artifacts with market value. This industry is generally fueled by the market for antiquities. The practice of treasure-hunting can be controversial, as locations such as sunken wrecks or cultural sites may be protected by national or international law concerned with property ownership, marine salvage, sovereign or state vessels, commercial diving regulations, protection of cultural heritage and trade controls.
Antarctica is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of 14,200,000 km2 (5,500,000 sq mi). Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of 1.9 km (1.2 mi).
Neuschwanstein was an enstatite chondrite meteorite that fell to Earth on 6 April 2002 at 22:20:18 GMT near Neuschwanstein Castle, Bavaria, at the Germany–Austria border.
Meteorite Men is a documentary reality television series featuring meteorite hunters 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.
The Sutter's Mill meteorite is a carbonaceous chondrite which entered the Earth's atmosphere and broke up at about 07:51 Pacific Time on April 22, 2012, with fragments landing in the United States. The name comes from Sutter's Mill, a California Gold Rush site, near which some pieces were recovered. Meteor astronomer Peter Jenniskens assigned Sutter's Mill (SM) numbers to each meteorite, with the documented find location preserving information about where a given meteorite was located in the impacting meteoroid. As of May 2014, 79 fragments had been publicly documented with a find location. The largest (SM53) weighs 205 grams (7.2 oz), and the second largest (SM50) weighs 42 grams (1.5 oz).
This is a glossary of terms used in meteoritics, the science of meteorites.
Patriot Hills is a line of rock hills 5 nautical miles (9 km) long, located 3 nautical miles (6 km) east of the north end of Independence Hills in Horseshoe Valley, Heritage Range, Western Antarctica.
The King Baudouin Ice Shelf in Dronning Maud Land, East Antarctica, is within the Norwegian part of Antarctica. It is named after King Baudouin of Belgium (1930-1993).
Catherine Margaret Corrigan, often known as Cari Corrigan, is an American scientist best known as a curator of the meteorite collection at the Smithsonian Institution. She is a scientist in the Department of Mineral Science at the National Museum of Natural History.
A blue-ice area is an ice-covered area of Antarctica where wind-driven snow transport and sublimation result in net mass loss from the ice surface in the absence of melting, forming a blue surface that contrasts with the more common white Antarctic surface. Such blue-ice areas typically form when the movement of both air and ice are obstructed by topographic obstacles such as mountains that emerge from the ice sheet, generating particular climatic conditions where the net snow accumulation is exceeded by wind-driven sublimation and snow transports.
Katherine Helen Joy is a Professor in Earth Sciences at the University of Manchester. Joy has studied lunar samples from the Apollo program as part of her research on meteorites and lunar science.
