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🔗 United States 🔗 Spaceflight 🔗 Telecommunications

The Iridium satellite constellation provides L-band voice and data information coverage to satellite phones, pagers and integrated transceivers over the entire Earth surface. Iridium Communications owns and operates the constellation, additionally selling equipment and access to its services. It was originally conceived by Bary Bertiger, Raymond J. Leopold and Ken Peterson in late 1987 (in 1988 protected by patents Motorola filed in their names) and then developed by Motorola on a fixed-price contract from July 29, 1993, to November 1, 1998, when the system became operational and commercially available.

The constellation consists of 66 active satellites in orbit, required for global coverage, and additional spare satellites to serve in case of failure. Satellites are in low Earth orbit at a height of approximately 781 km (485 mi) and inclination of 86.4°. Orbital velocity of the satellites is approximately 27,000 km/h (17,000 mph). Satellites communicate with neighboring satellites via K_a band inter-satellite links. Each satellite can have four inter-satellite links: one each to neighbors fore and aft in the same orbital plane, and one each to satellites in neighboring planes to either side. The satellites orbit from pole to same pole with an orbital period of roughly 100 minutes. This design means that there is excellent satellite visibility and service coverage especially at the North and South poles. The over-the-pole orbital design produces "seams" where satellites in counter-rotating planes next to one another are traveling in opposite directions. Cross-seam inter-satellite link hand-offs would have to happen very rapidly and cope with large Doppler shifts; therefore, Iridium supports inter-satellite links only between satellites orbiting in the same direction. The constellation of 66 active satellites has six orbital planes spaced 30° apart, with 11 satellites in each plane (not counting spares). The original concept was to have 77 satellites, which is where the name Iridium came from, being the element with the atomic number 77 and the satellites evoking the Bohr model image of electrons orbiting around the Earth as its nucleus. This reduced set of six planes is sufficient to cover the entire Earth surface at every moment.

Because of the shape of the original Iridium satellites' reflective antennas, the first generation satellites focus sunlight on a small area of the Earth surface in an incidental manner. This results in an effect called Iridium flares, where the satellite momentarily appears as one of the brightest objects in the night sky and can be seen even during daylight. Newer Iridium satellites do not produce flares.

🔗 Mass surveillance 🔗 Novels 🔗 Books 🔗 Novels/Science fiction 🔗 Science Fiction 🔗 Freedom of speech 🔗 Politics 🔗 Socialism

Nineteen Eighty-Four: A Novel, often published as 1984, is a dystopian novel by English novelist George Orwell. It was published in June 1949 by Secker & Warburg as Orwell's ninth and final book completed in his lifetime. The story was mostly written at Barnhill, a farmhouse on the Scottish island of Jura, at times while Orwell suffered from severe tuberculosis. Thematically, Nineteen Eighty-Four centres on the consequences of government over-reach, totalitarianism, mass surveillance, and repressive regimentation of all persons and behaviours within society.

The story takes place in an imagined future, the year 1984, when much of the world has fallen victim to perpetual war, omnipresent government surveillance, historical negationism, and propaganda. Great Britain, known as Airstrip One, has become a province of a superstate named Oceania that is ruled by the Party who employ the Thought Police to persecute individuality and independent thinking. Big Brother, the leader of the Party, enjoys an intense cult of personality despite the fact that he may not exist. The protagonist, Winston Smith, is a diligent and skillful rank-and-file worker and Party member who secretly hates the Party and dreams of rebellion. He enters a forbidden relationship with a co-worker, Julia.

Nineteen Eighty-Four has become a classic literary example of political and dystopian fiction. Many terms used in the novel have entered common usage, including Big Brother, doublethink, thoughtcrime, Newspeak, Room 101, telescreen, 2 + 2 = 5, prole, and memory hole. Nineteen Eighty-Four also popularised the adjective "Orwellian", connoting things such as official deception, secret surveillance, brazenly misleading terminology, and manipulation of recorded history by a totalitarian or authoritarian state. Time included it on its 100 best English-language novels from 1923 to 2005. It was placed on the Modern Library's 100 Best Novels, reaching No. 13 on the editors' list and No. 6 on the readers' list. In 2003, the novel was listed at No. 8 on The Big Read survey by the BBC. Parallels have been drawn between the novel's subject matter and real life instances of totalitarianism, mass surveillance, and violations of freedom of expression among other themes.

🔗 Extinction

An endling is the last known individual of a species or subspecies. Once the endling dies, the species becomes extinct. The word was coined in correspondence in the scientific journal Nature. Alternative names put forth for the last individual of its kind include ender and terminarch.

The word relict may also be used, but usually refers to a population, rather than an individual, that is the last of a species.

🔗 Computing 🔗 Computing/Early computers

The TX-0, for Transistorized Experimental computer zero, but affectionately referred to as tixo (pronounced "tix oh"), was an early fully transistorized computer and contained a then-huge 64K of 18-bit words of magnetic core memory. Construction of the TX-0 began in 1955 and ended in 1956. It was used continually through the 1960s at MIT. The TX-0 incorporated around 3600 Philco high-frequency surface-barrier transistors, the first transistor suitable for high-speed computers. The TX-0 and its direct descendant, the original PDP-1, were platforms for pioneering computer research and the development of what would later be called computer "hacker" culture.

🔗 Economics 🔗 Systems 🔗 Business 🔗 Sociology 🔗 Organizations 🔗 Engineering 🔗 Systems/Project management

Parkinson's law is the adage that "work expands so as to fill the time available for its completion". It is sometimes applied to the growth of bureaucracy in an organization.

🔗 Transport 🔗 Trains

The Cosmopolitan Railway was a proposed global railroad network advocated by William Gilpin, formerly the first territorial governor of Colorado (1861–62), in his 1890 treatise Cosmopolitan Railway: Compacting and Fusing Together All the World's Continents. Gilpin named his capital city of Denver as the "railroad centre of the West".

🔗 United States 🔗 Biography 🔗 Biography/arts and entertainment 🔗 United States/Massachusetts

Timothy Dexter (January 22, 1747 – October 23, 1806) was an American businessman noted for his writing and eccentricity.

🔗 United States 🔗 Media 🔗 Popular Culture 🔗 Georgia (U.S. state) 🔗 United States/United States Presidents 🔗 Animals in media

The Jimmy Carter rabbit incident, sensationalized as the "killer rabbit attack" by the press, involved a swamp rabbit (Sylvilagus aquaticus) that swam toward then-U.S. President Jimmy Carter's fishing boat on April 20, 1979. The incident caught the imagination of the media after Carter's press secretary, Jody Powell, mentioned the event to a correspondent months later.

Political opponents argued that the incident was symbolic of Carter's purported weakness. According to Powell, anti-Carter political commentators went so far as to blame it for the Soviet invasion of Afghanistan and the Iran hostage crisis.

🔗 Mathematics 🔗 Economics 🔗 Game theory

A Vickrey auction or sealed-bid second-price auction (SBSPA) is a type of sealed-bid auction. Bidders submit written bids without knowing the bid of the other people in the auction. The highest bidder wins but the price paid is the second-highest bid. This type of auction is strategically similar to an English auction and gives bidders an incentive to bid their true value. The auction was first described academically by Columbia University professor William Vickrey in 1961 though it had been used by stamp collectors since 1893. In 1797 Johann Wolfgang von Goethe sold a manuscript using a sealed-bid, second-price auction.

Vickrey's original paper mainly considered auctions where only a single, indivisible good is being sold. The terms Vickrey auction and second-price sealed-bid auction are, in this case only, equivalent and used interchangeably. In the case of multiple identical goods, the bidders submit inverse demand curves and pay the opportunity cost.

Vickrey auctions are much studied in economic literature but uncommon in practice. Generalized variants of the Vickrey auction for multiunit auctions exist, such as the generalized second-price auction used in Google's and Yahoo!'s online advertisement programmes (not incentive compatible) and the Vickrey–Clarke–Groves auction (incentive compatible).

🔗 United States 🔗 Video games 🔗 Computing 🔗 Film 🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Film/American cinema 🔗 United States/Film - American cinema 🔗 Science Fiction 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Military history/Cold War 🔗 Cold War 🔗 United States/Washington - Seattle 🔗 United States/Washington 🔗 Film/War films 🔗 Military history/War films

WarGames is a 1983 American science fiction techno-thriller film written by Lawrence Lasker and Walter F. Parkes and directed by John Badham. The film, which stars Matthew Broderick, Dabney Coleman, John Wood, and Ally Sheedy, follows David Lightman (Broderick), a young hacker who unwittingly accesses a United States military supercomputer programmed to simulate, predict and execute nuclear war against the Soviet Union.

WarGames was a critical and commercial success, grossing $125 million worldwide against a $12 million budget. The film was nominated for three Academy Awards.