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🔗 Computing 🔗 Computing/Software

The syntax of the Python programming language is the set of rules that defines how a Python program will be written and interpreted (by both the runtime system and by human readers). The Python language has many similarities to Perl, C, and Java. However, there are some definite differences between the languages.

🔗 Environment 🔗 Occupational Safety and Health 🔗 Brazil 🔗 Brazil/History of Brazil 🔗 Science Policy

The Goiânia accident [ɡojˈjɐniɐ] was a radioactive contamination accident that occurred on September 13, 1987, in Goiânia, in the Brazilian state of Goiás, after a forgotten radiotherapy source was taken from an abandoned hospital site in the city. It was subsequently handled by many people, resulting in four deaths. About 112,000 people were examined for radioactive contamination and 249 of them were found to have been contaminated.

In the cleanup operation, topsoil had to be removed from several sites, and several hundred houses were demolished. All the objects from within those houses, including personal possessions, were seized and incinerated. Time magazine has identified the accident as one of the world's "worst nuclear disasters" and the International Atomic Energy Agency called it "one of the world's worst radiological incidents".

🔗 Computing 🔗 Computing/Software

NeWS (Network extensible Window System) is a discontinued windowing system developed by Sun Microsystems in the mid-1980s. Originally known as "SunDew", its primary authors were James Gosling and David S. H. Rosenthal. The NeWS interpreter was based on PostScript (as was the later Display PostScript, although the two projects were otherwise unrelated) extending it to allow interaction and multiple "contexts" to support windows. Like PostScript, NeWS could be used as a complete programming language, but unlike PostScript, NeWS could be used to make complete interactive programs with mouse support and a GUI.

🔗 United States 🔗 Spaceflight 🔗 Philately 🔗 Guild of Copy Editors

The Apollo 15 postal covers incident, a 1972 NASA scandal, involved the astronauts of Apollo 15, who carried about 400 unauthorized postal covers into space and to the Moon's surface on the Lunar Module Falcon. Some of the envelopes were sold at high prices by West German stamp dealer Hermann Sieger, and are known as "Sieger covers". The crew of Apollo 15, David Scott, Alfred Worden and James Irwin, agreed to take payments for carrying the covers; though they returned the money, they were reprimanded by NASA. Amid much press coverage of the incident, the astronauts were called before a closed session of a Senate committee and never flew in space again.

The three astronauts and an acquaintance, Horst Eiermann, had agreed to have the covers made and taken into space. Each astronaut was to receive about $7,000. Scott arranged to have the covers postmarked on the morning of the Apollo 15 launch on July 26, 1971. They were packaged for space and brought to him as he prepared for liftoff. Due to an error, they were not included on the list of the personal items he was taking into space. The covers spent July 30 to August 2 on the Moon inside Falcon. On August 7, the date of splashdown, the covers were postmarked again on the recovery carrier USS Okinawa. One hundred were sent to Eiermann (and passed on to Sieger); the remaining covers were divided among the astronauts.

Worden had agreed to carry 144 additional covers, largely for an acquaintance, F. Herrick Herrick; these had been approved for travel to space. Apollo 15 carried a total of approximately 641 covers. In late 1971, when NASA learned that the Herrick covers were being sold, the astronauts' supervisor, Deke Slayton, warned Worden to avoid further commercialization of what he had been allowed to take into space. After Slayton heard of the Sieger arrangement, he removed the three as backup crew members for Apollo 17, though the astronauts had by then refused compensation from Sieger and Eiermann. The Sieger matter became generally known in the newspapers in June 1972. There was widespread coverage; some said astronauts should not be allowed to reap personal profits from NASA missions.

By 1977, all three former astronauts had left NASA. In 1983, Worden sued, and the covers were returned to them. One of the postal covers given to Sieger sold for over $50,000 in 2014.

🔗 Germany 🔗 Skepticism 🔗 Paranormal

An April 1561 broadsheet by Hans Glaser described a mass sighting of celestial phenomena or unidentified flying objects (UFO) above Nuremberg (then a Free Imperial City of the Holy Roman Empire). Ufologists have speculated that these phenomena may have been extraterrestrial spacecraft. Skeptics assert that the phenomenon was likely to have been another atmospheric phenomenon, such as a sun dog, although the print doesn't fit the usual classic description of the phenomena.

🔗 Military history/Early Muslim military history 🔗 Games

The two envelopes problem, also known as the exchange paradox, is a brain teaser, puzzle, or paradox in logic, probability, and recreational mathematics. It is of special interest in decision theory, and for the Bayesian interpretation of probability theory. Historically, it arose as a variant of the necktie paradox. The problem typically is introduced by formulating a hypothetical challenge of the following type:

It seems obvious that there is no point in switching envelopes as the situation is symmetric. However, because you stand to gain twice as much money if you switch while risking only a loss of half of what you currently have, it is possible to argue that it is more beneficial to switch. The problem is to show what is wrong with this argument.

🔗 Aviation 🔗 Disaster management 🔗 Aviation/Aviation accident 🔗 Lists

This list of missing aircraft includes all of the aircraft that have disappeared in flight for reasons that have never been definitely determined. According to Annex 13 of the International Civil Aviation Organization, an aircraft is considered to be missing "when the official search has been terminated and the wreckage has not been located". However, there still remains a "grey area" on how much wreckage needs to be found for a plane to be declared "recovered". This list does not include every aviator, or air passenger that has ever gone missing as these are separate categories.

In the tables below, each missing aircraft is defined (in the Aircraft column) using one or more identifying features. If the aircraft was known by a custom or personalized name (e.g. Pathfinder), that name is presented first (in italics) followed by the aircraft type (in parentheses). The make of aircraft, although not necessarily a unique identifier, is also provided where appropriate. Aircraft registrations began to be used in the early 20th century for individual identification, so this is also included in the later tables (in parentheses).

🔗 Internet 🔗 Internet culture 🔗 Linguistics 🔗 Linguistics/Applied Linguistics

Usenet () is a worldwide distributed discussion system available on computers. It was developed from the general-purpose Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Ellis conceived the idea in 1979, and it was established in 1980. Users read and post messages (called articles or posts, and collectively termed news) to one or more categories, known as newsgroups. Usenet resembles a bulletin board system (BBS) in many respects and is the precursor to Internet forums that are widely used today. Discussions are threaded, as with web forums and BBSs, though posts are stored on the server sequentially. The name comes from the term "users network".

A major difference between a BBS or web forum and Usenet is the absence of a central server and dedicated administrator. Usenet is distributed among a large, constantly changing conglomeration of servers that store and forward messages to one another via "news feeds". Individual users may read messages from and post messages to a local server, which may be operated by anyone.

Usenet is culturally and historically significant in the networked world, having given rise to, or popularized, many widely recognized concepts and terms such as "FAQ", "flame", sockpuppet, and "spam". In the 1990s, before access to the Internet became commonly affordable, Usenet connections via Fidonet's dial-up BBS networks made long-distance or worldwide discussions and other communication widespread, not needing a server, just (local) telephone service.

Digital Radio Frequency Memory (DRFM) is an electronic method for digitally capturing and retransmitting RF signals. DRFM systems are typically used in radar jamming, although applications in cellular communications are becoming more common.

🔗 Technology 🔗 Linguistics 🔗 Japan 🔗 Japan/Science and technology 🔗 Japan/CJKV

Mojibake (Japanese: 文字化け; IPA: [mod͡ʑibake]) is the garbled text that is the result of text being decoded using an unintended character encoding. The result is a systematic replacement of symbols with completely unrelated ones, often from a different writing system.

This display may include the generic replacement character ("�") in places where the binary representation is considered invalid. A replacement can also involve multiple consecutive symbols, as viewed in one encoding, when the same binary code constitutes one symbol in the other encoding. This is either because of differing constant length encoding (as in Asian 16-bit encodings vs European 8-bit encodings), or the use of variable length encodings (notably UTF-8 and UTF-16).

Failed rendering of glyphs due to either missing fonts or missing glyphs in a font is a different issue that is not to be confused with mojibake. Symptoms of this failed rendering include blocks with the code point displayed in hexadecimal or using the generic replacement character. Importantly, these replacements are valid and are the result of correct error handling by the software.