Main Page

An electron is a subatomic particle that carries a negative electric charge. It has no known substructure and is believed to be a point particle. An electron has a mass that is approximately 1/1836 that of the proton. The intrinsic angular momentum (spin) of the electron is a half integer value of ¹⁄₂, which means that it is a fermion. Electrons, which belong to the first generation of the lepton particle family, participate in gravitational, electromagnetic and weak interactions. Electrons have quantum mechanical properties of both a particle and a wave, so they can collide with other particles and be diffracted like light. Since an electron is a fermion, no two electrons can occupy the same quantum state, a property known as the Pauli exclusion principle. The electron was identified as a particle in 1897 by J. J. Thomson and his team of British physicists. In many physical phenomena, such as electricity, magnetism, and thermal conductivity, electrons play an essential role. An electron generates a magnetic field while moving, and it is deflected by external magnetic fields. The exchange or sharing of the electrons between two or more atoms is the main cause of chemical bonding. Electrons have many applications, including welding, cathode ray tubes, electron microscopes, radiation therapy, lasers and particle accelerators. (more...)

Recently featured: Han Dynasty – Death Valley National Park – Wind

From Wikipedia's newest articles:

• ... that actor Greg Kinnear (pictured) fills in for Jesus in Leonardo da Vinci's The Last Supper in the Parks and Recreation episode, "The Camel"?
• ... that in 1902, the Boveri-Sutton Chromosome Theory unified the genetic laws of Mendelian inheritance with the physical structures of chromosomes observed in cells?
• ... that after World War II, US General Douglas MacArthur placed Sankichi Takahashi on the list of the 59 most wanted Japanese?
• ... that the Joint Professional Military Education was established following greater awareness during WWII of a need for effective cooperation between the branches of the United States armed forces?
• ... that in spite of the Canadian telecommunications industry being gripped by "Telidon fever" in 1982, most attempts to commercialize the videotex system had ended by 1985?
• ... that Maryland politician William S. James served in all three branches of state government, as a trial magistrate, Senate President, and State Treasurer?
• ... that Trillium reliquum is an endangered species that exists at only 21 sites in Alabama, Georgia and South Carolina?
• ... that San Antonio's Sporting District, one of the largest red-light districts in the U.S. in the early 1900s, was so large that a tourist guide was published for visitors?
  
  Archive – Start a new article – Nominate an article

• Belgian Prime Minister Herman Van Rompuy (pictured) is chosen as the first permanent President of the European Council
• British politician Catherine Ashton is selected as the first High Representative of the European Union for Foreign Affairs and Security Policy.
• A United States district court finds the Army Corps of Engineers was negligent in maintaining New Orleans levees that contributed to flooding during Hurricane Katrina.
• The discovery of ancient crocodile genera Kaprosuchus and Laganosuchus is announced.
• The Original of Laura, a novel by Russian writer Vladimir Nabokov, is published posthumously despite his wish that its manuscript be burned.
  Wikinews – Recent deaths – More current events...

November 21: World Hello Day; World Television Day; Armed Forces Day in Bangladesh

• 1783 – The first successful untethered flight by humans in a hot air balloon was made by Jean-François Pilâtre de Rozier and François Laurent d'Arlandes in Paris.
• 1920 – Irish War of Independence: On Bloody Sunday in Dublin, the Irish Republican Army killed more than a dozen British intelligence officers known as the Cairo Gang, and the Auxiliaries of the Royal Irish Constabulary opened fire on players and spectators at a Gaelic football match in Croke Park.
• 1964 – The Verrazano-Narrows Bridge (pictured), a suspension bridge connecting Staten Island and Brooklyn in New York City at the Narrows, opened to traffic, becoming the largest suspension bridge in the world at the time.
• 1974 – Explosives placed in two central pubs in Birmingham, England, killed 21 people and injured 182 others, and eventually led to the arrest and imprisonment of six people that became known as the Birmingham Six.
• 1977 – "God Defend New Zealand" became New Zealand's second national anthem, on equal standing with "God Save the Queen", which had been the traditional one since 1840.

More anniversaries: November 20 – November 21 – November 22