Aarushhh/wikipedia-simple-splitted huggingface dataset:
Both use the same radio frequency range, but their modulation techniques are different. Both have been developed to replace cabling. Bluetooth wanted to get rid of the peripheral equipment cables, WLANs wanted to get rid of the cables needed to set up a LAN.

Bluetooth devices 

Bluetooth exists in many products, such as telephones, the Wii or PlayStation 3. It has recently been built into some electronic watches, modems and headsets. The technology is useful when transferring information between two or more devices that are near each other in low-bandwidth situations. Bluetooth is commonly used to transfer sound data with telephones (i.e. with a Bluetooth headset) or byte data with hand-held computers (transferring files).
Bluetooth uses protocols that make it easy to discover devices that are nearby, and to set up a connection between these devices. Bluetooth devices can advertise all the services they offer. Using services becomes easier; a lot of the setup related to security, networking or permissions is automatic.

Wireless LAN 
WLANs are more like traditional LANs. More configuration is needed to set up the network, and to make resources accessible by other devices in the network. WLAN devices also consume more power than Bluetooth ones. 
Sometimes WLANs are called wireless Ethernet. WLAN needs more resources to be set up, but it also offers faster transfer speeds. The security is also better than that offered by Bluetooth.

References

Computer protocols
Computer networking
Noraduz (or Noratus) is a site in the region of Gegharkunik in Armenia near Lake Sevan. It was formed a church dedicated to Sainte-mère-de-Dieu (built in the ninth century), and an exceptional site of medieval tombs. The tombstones are called Khachkars. Noraduz is the most important place for Khachkars in Armenia.

Related pages
Noraduz cemetery
Khachkar

References

Other websites 

Noraduz - Khachkars Field 
Noraduz Village

History of Armenia
The New York Yankees during 1921 (the 1921 season) was the 19th season for the Yankees in New York, and overall it was their 21st season. The season ended in the team having a record (the number of wins and losses) of 98-55 (98 wins, 55 losses). This was the first pennant won in Yankees history. They won the American League game pennant, replacing the previous winners, Cleveland Indians. The manager of their team was Miller Huggins. The Yankees home games were played on the Polo Grounds.

Season standings

Schedule

World Series

References
1921 New York Yankees team page at www.baseball-almanac.com

Other websites
Yankees game log courtesy baseball-almanac.com
1921 New York Yankees

New York Yankees
New York Yankees
Sports in New York City
1920s in New York (state)
20th century in New York City
The hominids are members of the biological family Hominidae (the great apes). This family includes humans, chimpanzees, gorillas and orangutans. "Great ape" is a common name rather than a taxonomic label, and people use it in different ways. Sometimes people mean to include humans in the category of “great apes,” and sometimes they mean non-human apes. Homo sapiens is definitely a hominid, as judged by all modern reference works.

Hominids range in weight from 48 kg to 270 kg. Males are larger than females. Hominids are primates with no tails, strong bodies, and well-developed forearms. Their thumbs (and big toes, except in humans) oppose the fingers, and form a grip. All digits have flattened nails.

At present, the family Hominidae includes four genera and eight species. However, if fossil hominids were included, all of the Australopithecines and the genus Homo would be members of the Hominidae family. Today, nonhuman great apes live only in the rainforests of equatorial Africa, Sumatra and Borneo.
The first hominid fossils are from the Miocene period. Archaeologists found these in Asia and Europe. Also in Asia, they found fossils of a huge version of the orangutan called Gigantopithecus, which is now extinct. Fossils also show that Neanderthals were in Europe and western Asia for at least half a million years before modern humans appeared.

Classification
Scholars do not agree on exactly how to classify the family Hominidae.

Past versions
In the past, the family Hominidae have been classified this way:
Family Hominidae: Great apes
 Subfamily Ponginae
 Genus Pongo  orangutans
 Subfamily Homininae
 Genus Gorilla – gorillas
 Genus Pan – chimpanzees
 Australopithecus† and other extinct relatives
 Genus Homo – humans

Modern version
A more recent classification shows humans and the Australopithecines as distinct from the rainforest apes. Two major reference works have supported this approach.
Superfamily Hominoidea
Family Hylobatidae
Genus Hylobates
Family Hominidae
Subfamily Ponginae
Genus Pongo
Subfamily Gorillinae
Genus Gorilla
Subfamily Homininae
Tribe Panini
Genus Pan
Tribe Hominini
Subtribe Australopithecina/Hominina
Genus Ardipithecus
Genus Australopithecus
Genus Kenyanthropus
Genus Sahelanthropus
Genus Orrorin
Genus Paranthropus
Genus Homo

Related pages
 Human timeline
 Human evolution

References

Hominids
The Acropolis of Athens is  the most famous acropolis. It is a large hill in the center of Athens, on which the Parthenon and other Greek buildings were built. It is often known as The Acropolis.
 The Acropolis is a group of ancient temples that were built on a high, rocky hill in Athens, Greece. The word acropolis even means 'high city' in Greek. Other cities have an acropolis, too, but the one in Athens is the most well-known.
The Acropolis of Athens is the most striking and complete ancient Greek monumental complex still existing in our times. It is situated on a hill of average height (156m) that rises in the basin of Athens. Its overall dimensions are approximately 170 by 350m.
 The buildings were a citadel where people could escape to if the city was attacked. The Acropolis was mostly destroyed by 580 B.C. The people of Athens weren't going to rebuild it. However, a hundred years later, Themistocles and Pericles persuaded them to build it again.
 Over the centuries, the Acropolis was many things: a home to kings, a citadel, a mythical home of the gods, a religious center and a tourist attraction. It has withstood bombardment, massive earthquakes and vandalism yet still stands as a reminder of the rich history of Greece.

Buildings and structures in Ancient Athens
1st millennium BC buildings and structures
Toki Pona (in Toki Pona it means good language or simple language) is a constructed (made-up) language. Sonja Lang (in past time Sonja Elen Kisa), a Canadian translator and linguist, made the language. It is based on simple ideas that are known to all cultures. It is not created to be an international auxiliary language (a language for communication between people speaking different languages). It is meant to test ideas about minimalism and pidgins. It is influenced by Taoist ideas. It has only 120 root words, although there is over 50,000 different possible combinations. Toki Pona relies very heavily on expressing ideas by using root words together. For example, jan pona means friend in Toki Pona (literally it means: good person).
Normally Toki Pona uses the Latin alphabet, but many Toki Pona speakers create other systems of writing for this language. Sonja Lang has made her own writing system for Toki Pona called sitelen pona (in English it means good writing or simple writing). It is based on pictograms (small drawings based off of how things look).

Example of text 
Lord's Prayer (translated by Pije/Jopi):

mama pi mi mute o, sina lon sewi kon.
nimi sina li sewi.
ma sina o kama.
jan o pali e wile sina lon sewi kon en lon ma.
o pana e moku pi tenpo suno ni tawa mi mute.
o weka e pali ike mi. sama la mi weka e pali ike pi jan ante.
o lawa ala e mi tawa ike.
o lawa e mi tan ike.
tenpo ali la sina jo e ma e wawa e pona.
Amen.

References

Other websites
Toki Pona official website
Toki pona lessons

Constructed languages
The Canadian Hurricane Centre (CHC) is a Canadian agency that is responsible for monitoring and tracking tropical cyclones that come near or affects Canadian territory. The agency warns people about on-coming tropical cyclones and makes hurricane advisories when needed. Its headquarters are in Dartmouth, Nova Scotia.

CHC usually works together with its United States counterpart, the National Hurricane Center in Miami, to coordinate the tracks and positions of all storms that show a possible threat to Canada.

While Atlantic hurricanes are normally uncommon in Canada, they do approach or strike from time to time. Among recent events are Hurricane Bob, which struck New Brunswick, in 1991, Hurricane Luis which struck Newfoundland in September 1995, Hurricane Hortense which struck Nova Scotia in September 1996, Hurricane Michael which struck Newfoundland in October 2000, and Hurricane Juan, which struck Nova Scotia in September 2003.
Other websites
CHC website
Official Canadian Weather Warnings 
Hurricane Bulletins for your wireless device 

Government agencies of Canada
V-type asteroids or Vestoids are asteroids that are similar to 4 Vesta. It is the largest asteroid in this class. This is where the name "V-type" comes from.

Asteroids
Vulcans are a humanoid species in the fictional Star Trek universe who hail from the planet Vulcan, and are noted for their attempt to live by reason and logic with no interference from emotion. (In One Epsiode of Star Trek The Next Generation Android Data and Spock work together to solve a Romulian cypher-Spock remarks that Data has acheived the perfect Vulcan state of Pure Logic without emotion; Data remarks that SPock despite his efforts  still feels emotion which Data is trying to acheive) They were the first extraterrestrial species encountered by Humans, and later became one of the founding members of the United Federation of Planets. Vulcans are featured in all six Star Trek series, four of which featured a Vulcan as a main character.

Related pages
 Vulcan, Alberta - a town in Canada that has incorporated Star Trek themes due to its name.
 Stoicism
Bibliography
 Star Trek: The Magazine v3#10 (February 2003 - "Romulan Propulsion Historical Overview" by Rick Sternbach & Tim Earls)
 Spock's World Diane Duane Pg. 359 Pocket Books, a division of Simon & Schuster Inc.  1230 Avenue of the Americas, NY, 10020 Paperback Edition 1989.

Fictional races
Star Trek
The W. M. Keck Observatory is a pair of two large, ground-based telescopes located at Mauna Kea, Hawaii. Sitting four km (more than two miles) above sea level, the paired telescopes are used to examine light from distant stars in great detail. The primary mirrors of each of the two telescopes are 10 meters (33 feet) across, making them slightly smaller than the Gran Telescopio Canarias primary mirrors.

However, all of the light collected by the Keck Observatory primary mirrors (75.76m2) is sent to the secondary mirror and the instruments, compared to GTC's primary mirror, which has an effective light-collection area of 73.4m2, or 25.4 square feet less than each of the Keck Observatory primary mirrors. Because of this fundamental difference in design, Keck Observatory's telescopes arguably remain the largest steerable, optical/infrared telescopes on Earth.

Related pages
 La Silla Observatory
 Very Large Telescope
Other websites 
 W.M. Keck Observatory (official site)
 The Mauna Kea Observatory (official site)

Observatories in the United States
Buildings and structures in Hawaii
Vulcan could mean:

Mythology
Vulcan (mythology), the blacksmith god of fire and volcanoes in Roman mythology
Hephaestus, the Greek god of smiths identified with Vulcan.

Fiction 
 Vulcan (Star Trek), a race in the fictional Star Trek universe
 Vulcan (Star Trek planet), home of the Vulcans
 Vulcan!, a 1978 Star Trek novel by Kathleen Sky
 Vulcan (DC Comics), a character from DC Comics
 Vulcan (comic), Ipc Comic produced in England from 1975-1976
 Vulcan (Marvel Comics), a character in the Marvel Comics universe
 Black Vulcan, a fictional African American superhero on the animated series Super Friends
 Vulcan, a fictional planet featured in the Doctor Who serial The Power of the Daleks
 Vulcan Raven, a character in Metal Gear Solid
Places 
 Vulcan, Alberta, Canada
 Vulcan Airport
 Vulcan, Romania, in Hunedoara County in the Jiu Valley
 Vulcan, Braşov, also in Romania in Braşov County
 Vulcan, Michigan, United States
 Vulcan, Missouri, United States
 Vulcan (volcano), a volcano in Papua New Guinea
 Vulcano, a small volcanic island  in the Tyrrhenian Sea
Companies 
 Vulcanair, an Italian based manufacturer of light twin-engined aircraft that took over Partenavia
 Vulcan (cars), a Southport, England based car manufacturer
 Vulcan Corporation, a materials manufacturing company in Clarksville, Tennessee
 Vulcan Foundry, a former British locomotive builder
 Vulcan Iron Works, a former United States locomotive builder
 Vulcan Materials Company, a construction materials company headquartered in Birmingham, Alabama
 Vulcan Inc., an investment company formed by Microsoft cofounder Paul Allen
 Stettiner Vulcan AG, a former shipyard in Hamburg, Germany
 Vulcan (shipyard) (1857–1944), the shipyard in Szczecin, Poland
 Vulcan Media, an educational software company from Poland
 Vulcan Software, a British computer game company
 Vulcan Stoves, a maker of commercial ranges, ovens, steam equipment, fryers griddles and broilers
Vehicles 
 Avro Vulcan, British delta-wing subsonic bomber aircraft
 Vickers Vulcan, a single engined biplane of the 1920s
 Ford Vulcan engine, a 3.0L V6 automobile engine
 Kawasaki Vulcan, a cruiser-type motorcycle
 Kawasaki Vulcan 400 Classic
 Kawasaki Vulcan 800 Drifter
 M167 Vulcan, a towed short-range air defense gun
 M163 VADS (Vulcan Air Defense System), a self-propelled anti-aircraft gun
 Vulcan (1874-1892), one of the ten South Devon Railway Buffalo class steam locomotives
 Vulcan (1951-1967), one of the BR 'Britannia' Class locomotives
Vulcan Railcars are a type of railcar found in preservation in New Zealand.
 HMS Vulcan, either one of two Royal Navy ships, or a Royal Navy shore establishment at Dounreay, Scotland, dedicated to the development of nuclear power
Science 
 Vulcan (hypothetical planet), a hypothetical planet between Mercury and the Sun, and Vulcanoid asteroids, hypothetical minor planets in the same place
 Vulcanization, a chemical process to improve the strength and durability of rubber
 Vulcan laser, the most intensely focused in the world, based at the Rutherford Appleton Laboratory in Chilton, Oxfordshire.

Computing 
 Vulcan processor, a type of central processing unit
 VULCAN (operating system), an operating system for some 24-bit Datacraft/Harris Corporation minicomputers
 Vulcan (programming language), a programming language, now known as dBase
Other uses 
 The "Vulcans" are the nickname of California University of Pennsylvania's sports teams.
 Vulcan statue, the largest cast iron statue in the world and the symbol of Birmingham, Alabama
 Vulcan of the alchemists, the patron deity associated with Paracelsian alchemy
 Birmingham Vulcans, a 1975 World Football League team
 M61 Vulcan, a 20mm six-barreled gatling gun
 Vulcan M-11-9, a semi-automatic, closed bolt pistol manufactured by Vulcan Armament
 The Vulcans, an informal name of George W. Bush's foreign policy advisory team for the 2000 U.S. presidential election
 The Vulcan, an occasional magazine from various organizations within the Young Fine Gael, the youth wing of the Irish Fine Gael political party
 Vulcan, the title of an EP and a song by the rock band Snake River Conspiracy
 Operation Vulcan, Allied action in Tunisia during World War II

Related pages 
 Vulcana - Welsh female bodybuilder
 Volcano
The HED meteorites are a group of achondrite meteorite types:
 Howardites
 Eucrites
 Diogenites
 
These are all thought to have come from the crust of the asteroid 4 Vesta. Their differences are due to different geologic histories of the parent rock. Their crystallization ages are between 4.43 and 4.55 billion years ago, by their radioisotope ratios.

References

Meteorites
A metamorphic rock is a type of rock which has been changed by extreme heat and pressure. Its name is from 'morph' (meaning form), and 'meta' (meaning change).

The original rock gets heated (temperatures greater than 150 to 200 °C) and pressured (1500 bars). This causes profound physical and/or chemical change. The original rock may be sedimentary rock, igneous rock or another older metamorphic rock.

There is always more pressure and higher temperature under the Earth's surface. In the root of a mountain chain or a volcano these forces will be enough to change shape of the strata and the minerals it is made of. Sedimentary rock which has been near such forces often looks as if a giant had twisted it and heated it over a fire. Examples of metamorphic rock:
 Marble is a metamorphic rock formed from limestone.
 Slate is a metamorphic mudstone or shale.
 Quartzite is a metamorphic sandstone.
The recrystallisation of minerals after heating generally causes the destruction of any fossils the rocks might have contained. These rocks are formed when igneous or sedimentary rocks are subjected to extreme heat and pressure. As a result, they undergo a complete change in their form and characteristics. Rocks who have been changed in this way are called metamorphic rocks.

Types of metamorphism

Regional metamorphism

Regional metamorphism, or dynamic metamorphism, occurs in great masses of rock. Rocks can be metamorphosed just by being at great depths below the Earth's surface. There they get high temperatures and the great weight of the rock layers above.
Much of the lower continental crust is metamorphic, except for recent igneous intrusions. Horizontal tectonic movements such as the collision of continents create orogenic belts. High temperature, pressures and deformation occurs along these belts. If the metamorphosed rocks are later uplifted and exposed by erosion, they are seen as long belts or other large areas at the surface.

Contact metamorphism

Contact metamorphism occurs when magma is injected into the surrounding solid rock (country rock). The changes that occur are greatest where the magma comes into contact with the rock. The temperatures were highest there and decreased with distance from it.

Metamorphic minerals 
Every mineral is stable only within certain limits. When certain minerals appear in metamorphic rocks this shows the approximate temperatures and pressures the rock experienced. These minerals are known as index minerals. Sillimanite, kyanite, staurolite, andalusite, and some garnet are examples.
Other minerals, such as olivines, pyroxenes, amphiboles, micas, feldspars, and quartz may be found in metamorphic rocks. These minerals formed during the crystallization of igneous rocks. They are stable at high temperatures and pressures and may remain chemically unchanged during the metamorphic process.

Related pages 
 List of rocks
 Igneous rock
 Sedimentary rock
 List of minerals

References

Other websites 

 Metamorphic textures - Middle East Technical University 
 Metamorphism - U. of Alabama 
 Types of metamorphism - Tulane U.
 Contact metamorphism example 

Metamorphic rocks
Extrusive means to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out (extrudes) onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. This is opposed to intrusive rock formation, in which magma does not reach the surface.

Extruded when talking about an artificial material like soft metals like aluminium, plastic or glass means that it is pushed out of a nozzle when the material is in a soft state. The shape of the nozzle will vary depending on the shape required in the finished product

Geology
An intrusion is magma (melted rock) which cools and becomes solid under the Earth's surface.  It occurs when there are lines of weakness such as faults, joints, or bedding planes in the crust. Then magma enters these lines of weakness.  By contrast, an extrusion is magma which cools into rock above the surface of the crust. Both intrusive and extrusive rocks are classed as igneous rocks.

The process of forming intrusive rocks may take millions of years. As the rock slowly cools into a solid, the different parts of the magma crystallize into minerals. The crystals are usually larger than in extrusive rocks. Many mountain ranges, such as the Sierra Nevada in California, are formed mostly by intrusive rock. Often they are huge granite (or related rock) formations.
Intrusions vary widely, from mountain range sized batholiths to thin vein-like fracture fillings. When exposed by erosion, these cores called batholiths may occupy huge areas of Earth's surface. Large bodies of magma that solidify underground before they reach the surface of the crust are called plutons.

Intrusive structures may go between bedding planes of earlier 'country' rock. A sill is an intrusion which makes a table along bedding planes. A dyke is an intrusion which moves up, crossing older strata.

Related pages 
Volcanic plug

Geology
Igneous rocks
Radiation pressure is the pressure exerted upon any surface exposed to electromagnetic radiation. If absorbed, the pressure is the energy flux density divided by the speed of light. If the radiation is totally reflected, the radiation pressure is doubled.  This happens because the waves that make up electromagnetic radiation carry momentum with them and pass that momentum on when they reach a surface.

A Crookes radiometer appears to demonstrate the pressure of light, but instead it demonstrate the energy that light brings to a surface.  The black side of each paddle absorbs most of the light's energy an causes the air near that surface to have a higher pressure.  So, while a Crookes radiometer turns because of pressure, it is air pressure caused by the heat energy that light brings to the device.
Solar radiation at Earth
The solar radiation at Earth's distance from the Sun has an energy flux density of 1370 W/m2, and more than half of this energy reaches surface.  A calculation shows that this value of the flux would cause on an absorbing surface to experience 4.6 µPa of radiation pressure.  A convenient way to compare the Sun's energy flux and radiation pressure is to imagine the pressure and energy deposited on one square meter:

Power =  (or about 1.4 kilowatts.) 
Force = 

To understand how small a micro-newton is, convert calculate how much mass you need on Earth to get that force using :
Mass =  (or about ½ milligram.)

The difference between the energy flux and the pressure is like the difference between the heat coming through a large window and the weight of a very small mosquito.

References

Further reading
 Demir, Dilek,"A table-top demonstration of radiation pressure",2011, Diplomathesis, E-Theses univie (http://othes.univie.ac.at/16381/)

electromagnetism
Kirkwood gaps are areas of the asteroid belt where asteroids are unusually scarce, as seen in the graph on the right. They are caused by orbital resonances with Jupiter.

The gaps were first noticed in 1857 by Daniel Kirkwood, who also correctly explained their origin in the orbital resonances with Jupiter while a professor at Jefferson College in Canonsburg, Pennsylvania.

References

Other websites 
 Article on Kirkwood gaps at Wolfram's scienceworld
 A method to create a short-term simulation .

Asteroids
Jupiter
Ca-Al-rich inclusions (CAIs) are inclusions found in  carbonaceous chondrites. These inclusions are about  long. They are light-colored and made of calcium and aluminum. High-temperature minerals are often found in CAIs. These objects are among the first solid objects to be created by the cooling  of a protoplanetary disk. CAIs are formed at much higher temperatures than the associated chondrules. They may have survived many high-temperature events while most chondrules are created in a single melting event.

The isotopic anomalies of CAIs give important information about the creation of the solar system. The studying of them suggests that the solar nebula collapsed soon after a nearby supernova. Radiometric dating shows that the CAIs formed about 2 million years before the chondrules formed.
References
 Gilmour J. 2002. The Solar System's first clocks Science 297, 1658-1659. 
 Amelin Y. et al. 2002. Lead isotopic ages of chondrules and calcium-aluminum-rich inclusions Science, 297, 1678-1683.
 Krot A.N. 2002.  Dating the earliest solids in our Solar System. Planetary science research discoveries. http://www.psrd.hawaii.edu/Sept02/isotopicAges.html
 Shukolyukov A. & Lugmair G.W. 2002. Chronology of asteroid accretion and differentiation 687-695, in Bottke W.F. et al. (eds) Asteroids III. University of Arizona Press. 

Meteorites
Eucrites are achondritic stony meteorites that originate from the surface of the asteroid 4 Vesta, and as such are part of the HED meteorite group. They are the most common achondrite group with well over 100 distinct finds at present.

Eucrites consist of basaltic rock from the crust of 4 Vesta. They are mostly made up of Ca-poor pyroxene, pigeonite, and Ca-rich plagioclase (anorthite).

Eucrites are named from a Greek word meaning "easily distinguished".

Other websites 
 HED Group - Meteorites from Vesta

Meteorites
Comet 81P/Wild, also known as Wild 2, is a comet named after Swiss astronomer Paul Wild (pronounced Vilt), who discovered it in 1978.

It is believed that for most of its 4.5 billion-year lifetime, Wild 2 had a more distant and circular orbit. In 1974, it passed within only about one million kilometers of the planet Jupiter, whose strong gravitational pull altered the comet's orbit and brought it into the inner solar system. Its orbital period changed from 40 years to about 6 years, and its perihelion is now about 1.59 AU (astronomical unit).

Gallery

Other websites 
 NASA Team Analyzes Stardust Particle Capture  January 18, 2006
 NASA/JPL homepage for Stardust project
 Stardust@Home Volunteer Particle Analysis Project 
 IAU Ephemerides page for 81P
 Catalogue of all 72 raw images of Wild 2 

Comets
A barrel is a part of a gun. It is a long metal tube that the bullet or projectile goes through after it is fired. Guns can have many different sizes of barrels. Usually, longer barrels make it easier for the bullet to hit the target more often. Barrels usually have spiral grooves on the inside called rifling. Barrels with grooves spin the projectile around faster as it exits the gun. This makes the projectile more stable in flight and more accurate.

References 

Firearm components
A shell is a type of projectile used in weapons. It is filled with explosive or other things such as an incendiary device. It is similar to a bomb but is made to be shot out of a gun. Shells are usually large caliber projectiles fired by artillery, armored vehicles (including tanks), and warships. A fuze detonates the explosive or releases whatever else the shell may be carrying.

Anti-tank guns fire thick shells without much explosive inside. Shells usually have the shape of a cylinder but taper towards the front end to form a point. However, special shells may use other shapes.

Artillery
An ion thruster is a type of spacecraft thruster. It works by using static electricity or magnetism to push ions (atoms that have an electric charge) out of the back of the spacecraft. It takes a very long time for the spacecraft to speed up, but the fuel is used very efficiently. A thruster that has very high efficiency is said to have a high specific impulse.

It has to be carried into outer space by a regular rocket, because the ions don't push hard enough for it to escape the Earth's atmosphere, but after it gets to outer space it can travel a very long way. An ion thruster needs lots of electricity to work, so the spacecraft needs a very good way of producing electricity, such as solar panels or a nuclear reactor.
Ion thrusters are good for travelling between things in space that are very far away from each other. One example of this is interplanetary travel. Ion thrusters are good for this because they are efficient and can thrust for very long times. Chemical rocket thrusters ("regular" rocket thrusters) can only burn for short times, because they use fuel quickly and not efficiently. Because of this, chemical rockets only thrust for short times at important places during the journey. Ion thrusters use fuel very slowly and very efficiently. This means that ion thrusters can thrust continuously for the entire journey. In a slightly surprising way, this makes spacecraft that use ion thrusters faster than spacecraft that use chemical rockets.

Ion thrusters have been used on small space probes. In 2011 the NASA space probe called Dawn used an ion thruster to get to the asteroid named Vesta. In 2015 the thruster brought Dawn to the dwarf planet named Ceres.

References 

Rockets
A pistol  is a handgun. The word may be used broadly to mean any handgun, or narrowly to mean only a magazine pistol, as distinct from a revolver. 

In a magazine pistol, the cartridges are in a magazine, which is a metal or plastic box. The magazine is usually inside the handle of the pistol. When the pistol is fired, the empty cartridge pops out, and the next one comes up into position. The magazine is spring-loaded so it pushes the next bullet into place as the empty cartridge is ejected. For that reason pistols are sometimes called "semi-automatic". When the magazine runs out of cartridges, it can be reloaded by inserting more cartridges. 

The term has long been variously used. For example, in the American Old West revolvers were used but were then (and even today by some) called pistols. The word "pistol" entered English before 1600, from the French. At that time it usually meant a single-shot handgun.

Gun safety
Gun safety 

One of the most important rules of gun safety is to keep guns out of the hands of children. Guns should be locked up and kept away from children and others who do not appreciate how deadly they are. Pistols like all guns should always be handled carefully. Always keep the gun pointed in a safe direction. A shooter should keep their fingers away from the trigger until the moment they intend to shoot. Always respect guns as a tool that can cause harm if used incorrectly. Always assume a gun is loaded until you are certain it is not.
Pros and cons of pistols 
 
The advantage of pistols over revolvers lies in the somewhat faster reloading of magazines that carry more bullets that a revolver's five or six rounds. This is why most police and military organizations use pistols. Also, pistols are often thinner and can be worn concealed better than revolvers. 
 
Pistols have a few disadvantages when compared to revolvers. They are more complicated and have more moving parts. A pistol may use heavier springs that younger and elderly shooters may find difficult to use.

Modern pistols usually only fire one shot every time you pull the trigger. Some special pistols, called machine pistols, can fire more than one shot at a time. Some famous pistols are the Colt M1911 and the Beretta 92. 

Pistols were not often used in the western United States during the 1800s. They used revolvers. The first  successful pistol being used then was the Borchardt C-93. It was designed in 1893, and became available in 1894.
Related pages
 Air gun
 Revolver
 Gun safety
 Second Amendment to the United States Constitution

References

Other websites 
 Gun Law in the UK
 Gun laws around the world. Huffington Post
 Gun Control: What We Can Learn From Other Advanced Countries. Newsweek
 Strict local gun laws limit servicemembers’ ownership on overseas bases. Stars and Stripes
A submachine gun is a type of gun that shoots many bullets, usually pistol bullets, when one holds down the trigger. A submachine gun is smaller than a machine gun and can easily be carried by one person. They are often used where people need to defend themselves in small areas, or people need to fire many bullets quickly. The first submachine guns were invented in the early 1900s. They are often used by the police and counter-terrorism units .

History
In the early 20th century, experiments were made by converting  pistols from semi to fully automatic firearms. Automatic weapons with gunstock and firing pistol rounds were developed around the same time during World War I, by Italy, Germany, and the United States. The first dedicated designs were developed in the latter stages of World War I both as improvements on earlier stocked pistols, and to offer an advantage in trench warfare.
They were popularized in the 1920s and '30s as weapon of choice of American gangsters and police, in the form of the famous Thompson submachine gun, commonly referred to as the "Tommy Gun". Submachine guns rose to prominence as a frontline close-quarters combat weapon and commando firearm during World War II. They are now widely used by police SWAT, military commando, paramilitary, and counter-terror team members for a variety of situations. 

Submachine guns are highly effective in close quarters; their lower-powered pistol cartridges make them generally more controllable in fully-automatic fire compared to assault rifles, while their small size and light weight grant maneuverability.  However, pistol bullets often are stopped by body armor or cover, and are short-ranged compared to intermediate and rifle cartridges.
World War II developments 
World War II developments were many and interesting. In Germany the development of machine carbines (Maschinenkarabiner) was notable.  From 1939 onwards the German Army analyzed combat conditions and developed new tactics and equipment requirements. The existing 7.92x57mm rifle cartridge was more powerful and long ranged than needed. Most combat took place at ranges less than 400 m (440 yards). A less powerful round (bullet) could be used. This meant a soldier could carry more ammunition, the weapon could be shorter, lighter and with less recoil. The gun could be an automatic.

Achieving this took time. Work in 1941 and 1942 led at last to a reliable weapon, the StG 44 (Sturmgewehr 44) "assault rifle 44". This was then produced in large numbers (over 600,000). It came too late to effect the Second World War, but was later adapted as the Soviet AK 47.

References

Other websites 
 WW2-era Small Arms
 Submachine gun -Citizendium
Elena Vladimirovna Pitjeva is a Russian theoretical physicist at the Institute of Applied Astronomy, Russian Academy of Sciences, St. Petersburg. She is noted for her work on ephemerides and is currently head of the Laboratory of Ephemeris Astronomy at the Institute of Applied Astronomy. Pitjeva is a member of the International Astronomical Union Commission 4: Ephemerides.

Education
Pitjeva earned her undergraduate degree from the Faculty of Mathematics and Mechanics at A. A. Zhdanov Leningrad State University in 1972 in the specialty of astronomy. She earned an M.A. in theoretical physics in 1994 and a Ph.D. in theoretical physics in 2005. She was a student of Professor G.A. Krasinski.

Publications (selection)

References

Other websites
Laboratory of Ephemeris Astronomy, Institute of Applied Astronomy 

Russian astronomers
Living people
Year of birth missing (living people)
The Socialist Reich Party of Germany (German: Sozialistische Reichspartei Deutschlands) was a political party in West Germany. It was formed in 1949.

It was openly Neo-Nazi and admired Hitler. It split from the German Empire Party. Leaders included Otto Ernst Remer, a former Major General, and Fritz Dorls.

The SRP claimed West Germany's first Chancellor, Konrad Adenauer only did what the United States told, and that Karl Dönitz was the last legal of Germany.

The SRP also said that the Holocaust never happened, and that the ovens of the Dachau concentration camp were built by the United States after 1945. The SRP also wanted Europe to be led by a reunited German Reich, and that it would not be capitalist or communist.
The SRP never criticised the Soviet Union because the Russians funded the SRP because it was anti-American. The only other party modern in postwar Germany was the Communist Party of Germany. It did not get Soviet funds because the Russians thought it was useless. SRP leader Remer once said that if the USSR ever did invade Germany, he would "show the Russians the way to the Rhine".

The SRP had its own paramilitary organisation, the Reichsfront.

The SRP had about ten thousand members and it won 16 seats in the Lower Saxony Landtag election, and 8 seats Bremen.

It was banned in 1952 by the Federal Constitutional Court of Germany, the only court with the power to do so.

Notes

Other websites 
 Germany's New Nazis 1951 pamphlet about the SRP and other neo--nazi groups

Former political parties in Germany
Neo-Nazism
West Germany
1949 establishments in Germany
1950s disestablishments in Germany
The International Fight League was an American mixed martial arts (MMA) league and is the world's first MMA league. It was founded on January 7, 2006 and closed on July 31, 2008.

Instead of the established norm for MMA events, where matchups are strictly one-on-one affairs, each IFL card was a showdown between two teams of five fighters, each fighter fighting one match against another on the opposing team. The IFL was shown in the United States on Fox Sports Net and MyNetworkTV.

Other websites 
IFL - Official Website

Mixed martial arts organizations
2006 establishments in the United States
2008 disestablishments in the United States
Anton Pavlovich Chekhov (January 29, 1860 - July 15, 1904) was a Russian writer who wrote short stories and plays.

Early life 
Anton Chekhov was born in Taganrog, which is a city in Russia. His father, Pavel, was the owner of a grocery store. His mother, Yevgeniya, sometimes told Anton stories about her childhood.

In 1876, Chekhov's father went bankrupt. From then on, Chekhov's family was very poor. Anton Chekhov had to pay for his own education. He paid for it by tutoring (teaching) other students, catching birds and selling them, and writing short stories for newspapers. When he had extra money, he sent it to his family. While he was at school, he read many books by famous authors, for example Miguel de Cervantes and Arthur Schopenhauer.

In 1879, Chekhov went to Moscow University.

Writing career
Writing career 

While he was at Moscow University, Chekhov wrote many short stories to pay for his schooling and to help his family. In 1886, one of the most famous newspapers in Russia, New Times, asked him to write stories for them. Soon, his stories started to get famous, and other writers read his work and liked it. He wrote a book of stories called At Dusk that won the Pushkin Prize, an award for good writing.

In 1887, Chekhov wrote a play called Ivanov. Chekhov did not like the play, but critics loved it.

In 1890, Chekhov went to Sakhalin Island, a penal colony (prison). He talked to many prisoners and found out that they were treated very badly. The prisoners were often beaten. There were also children there. He was angry, and wrote about it in a book called The Island Of Sakhalin and in a short story called The Murder.
In 1892, he bought a house and some land near Moscow called Melikhovo. While he was there, he helped the people who lived nearby. He brought them food and clothing, and medicine when they were sick. Since he was trained as a doctor, he knew how to take care of them.

While at Melikhovo, he started to write a play called The Seagull. When it was first performed, it went very badly, and the audience did not like it. Later, it was performed at another theater, the Moscow Art Theater, where the performances went better. Soon after this, he had another play performed, called Uncle Vanya. He later wrote two more great plays: Three Sisters and The Cherry Orchard. All four plays are still often performed today.

Marriage, sickness, and death
In 1897, he became sick. Doctors told him that he had tuberculosis, a lung disease, and that he should change his life to be healthier. He moved to Yalta and bought a house there. In 1901 he married a woman named Olga Knipper. At Yalta, he wrote some of his most famous stories, including a story called The Lady With The Dog.

By 1904, Chekhov was very sick. He died on the 15th of July in Germany. Thousands of people were very sad when he died. He was buried in Novodevichy Cemetery.

Influence 

Chekhov influenced many important writers, including George Bernard Shaw, James Joyce, and Virginia Woolf. His short stories are still read by many people around the world.

Related pages
List of Russian-language novelists

Other websites
Other websites 

 . All Constance Garnett's translations of the short stories and letters are available, plus the edition of the Note-book translated by S.S. Koteliansky and Leonard Woolf (see the "References" section for print publication details of all of these). The site also has translations of all the plays.
 Антон Павлович Чехов Texts of Chekhov's works in the original Russian. Retrieved 16 February 2007.
 Web page A.P. Chekhov  on a site of the Taganrog Central Public Library named after A. P. Chekhov

1860 births
1904 deaths
Deaths from tuberculosis
Disease-related deaths in Germany
Russian writers
Labour and Social Justice – The Electoral Alternative ( or WASG) was a German political party founded in 2005 by people who did not like the Social Democratic–Green government.

On 16 June 2007, it merged with The Left Party.PDS to form the a party The Left (Die Linke) party. At the time of its merger with The Left Party.PDS about 11,600 people were members.

2005 establishments in Germany
2007 disestablishments in Europe
Former political parties in Germany
The Left (Germany)
2000s disestablishments in Germany
The Deutsche Reichspartei (DRP) (German Reich Party, German Imperial Party or German Empire Party) was a nationalist political party in West Germany. It was a merger of the German Conservative Party - Deutsche Right Party (DKP-DRP) and the old Hessian Nationaldemokratischen Partei (NDP).

Some of the DRP's founders were: Alexander Andrae, Oskar Lutz, Hans Bernd von Grünberg, Wilhelm Meinberg, Otto Heß, Hans Schikora, Heinrich Kunstmann, Adolf von Thadden.

In 1949 the Sozialistische Reichspartei (SRP) split from the DRP. This was because the Empire Party was not neo-Nazi, and did not want to be associated with Adolf Hitler.  Instead the party preferred to say how good the Second German Empire (1870-1919) was. 

The Deutsche Reichspartei did become more national socialist after 1952. This is when the Sozialistische Reichspartei was banned by the Federal Constitutional Court of Germany and a lot of its members re-joined the Empire Party.
The party was not very successful in the 1950s, but seemed to be getting more popular after the state elections of 1959. But the success did not last, and the party held its final conference in 1964 when it was dissolved. It was quickly replaced by the new Nationaldemokratische Partei Deutschlands.

Other websites 
 Germany's New Nazis 1951 pamphlet about the DRP and other neo--nazi groups

Former political parties in Germany
Neo-Nazism
West Germany
1964 disestablishments
is a prefecture in the Kyūshū region of Japan on the island of Kyūshū. The capital city is Fukuoka.

History 
The area of Fukuoka Prefecture includes the old provinces of Chikugo, Chikuzen, and Buzen.

Timeline
 November 19, 1274 (Bun'ei 11, 20th day of the 10th month): Battle of Bun'ei
 August 15, 1281 (Kōan 4, 30th day of the 7th month): Battle of Kōan

Geography 
Fukuoka Prefecture faces the sea on three sides.  The prefecture borders Saga, Ōita, and Kumamoto prefectures.  Fukuoka is near Yamaguchi Prefecture across the Kanmon Straits.

Fukuoka includes the two largest cities on Kyūshū, Fukuoka and Kitakyūshū. Small islands are near the north coast of the prefecture.

Cities
There are 28 cities in the prefecture:

Towns and villages
These are the towns and villages in each district of the prefecture

National Parks
National Parks are established in about 18% of the total land area of the prefecture.
Shrines and Temples
Kōra taisha, Sumiyoshi-jinja, Hakosagi-gū and Usa-jinjū are the chief Shinto shrines (ichinomiya) in the prefecture.

Related pages
 Provinces of Japan
 Prefectures of Japan
 List of regions of Japan
 List of islands of Japan
 Kyushu National Museum
 Giravanz Kitakyushu
 Fukuoka Art Museum
 Kyushu National Museum
 Dazaifu

References

Other websites 

 Fukuoka Prefecture website ;  
 http://www.kyushu.com/fukuoka/ 
 http://diddlefinger.com/m/fukuokaken/
Evening Prayer (often called Evensong), in the Anglican Church, is the traditional service when people come to church to worship in the late afternoon or early evening.  In cathedrals in Britain and in some of the old university chapels it is a service that is sung by a choir nearly every day of the week (there is usually one day of the week when there is no choir and everything is spoken).  In cathedrals it is usually just the choir and the priests who sing, while the congregation listen.  There is sometimes one hymn at the end in which the congregation can join in.  Evensong in churches will have more singing for the congregation to join in.

Development and meaning of Evensong
The form of Evensong used today was developed by Thomas Cranmer in the 16th century.  There were two kinds of services, called "vespers" and "compline" that used to be sung every day by monks in monasteries.  Cranmer took some of the words that were used in both these services and made today's form of Evening Prayer (Evensong).
The main idea in Evensong is the celebration of the incarnation of Christ: this is the story about Christ coming to the world in the form of a person and living among people.  The words of the Magnificat and the Nunc Dimittis are always used in the service.  The Magnificat is the song that Mary sang when she was told that she was going to have a baby who would be God’s son.  The Nunc Dimittis is the song that was sung by the priest Simeon who had been promised by God that he would live long enough to see Jesus.  Both these sets of words are from the New Testament.

Many churches now use the words from Common Worship or some other modern prayer book for their services.  However, when Evensong is sung by a choir the words used are usually from the old traditional  Book of Common Prayer (1662).  This is because, for more than four centuries, so much great music has been composed that uses these words.
Because there is no communion at evensong, the service can be led by a layperson (someone who is not a “qualified” priest).

Parts of the Evensong service
An evensong service will consist of the following:

Prayers: a confession, an absolution (if a priest is present) and the Lord's Prayer.
 responsory prayers (sung alternately by priest and choir).
one or two psalms.
Two lessons (readings) from the Bible.  The first is usually taken from the Old Testament and the second from the New Testament.  Each lesson is followed by (one of):
Two canticles, usually the Magnificat and Nunc Dimittis.
The Apostles' Creed.
Several prayers and responses, including the Kyrie eleison and the Lord's Prayer.
An anthem
More prayers and a blessing

The organist usually plays some organ music before and after the service.  On Sundays there may be a sermon.

Music
Music

In churches the Magnificat and the Nunc dimittis (canticles), like the psalm, are often sung to a chant.  This is a tune which repeats itself for every verse or every two verses and is sung to the natural rhythm in which it would be spoken.  In cathedrals, or in churches with a good choir, the two canticles are sung to special music (like an anthem) composed by some well-known composer.  There is usually an organ accompaniment.