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πŸ”— The Cuckoo's Egg

πŸ”— Espionage πŸ”— Books πŸ”— Computer Security πŸ”— Computer Security/Computing

The Cuckoo's Egg: Tracking a Spy Through the Maze of Computer Espionage is a 1989 book written by Clifford Stoll. It is his first-person account of the hunt for a computer hacker who broke into a computer at the Lawrence Berkeley National Laboratory (LBNL).

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πŸ”— Wow signal

πŸ”— History πŸ”— Physics πŸ”— Telecommunications πŸ”— Skepticism πŸ”— Astronomy πŸ”— History of Science πŸ”— Physics/History πŸ”— Paranormal

The Wow! signal was a strong narrowband radio signal received on August 15, 1977, by Ohio State University's Big Ear radio telescope in the United States, then used to support the search for extraterrestrial intelligence. The signal appeared to come from the direction of the constellation Sagittarius and bore the expected hallmarks of extraterrestrial origin.

Astronomer Jerry R. Ehman discovered the anomaly a few days later while reviewing the recorded data. He was so impressed by the result that he circled the reading on the computer printout, "6EQUJ5", and wrote the comment "Wow!" on its side, leading to the event's widely used name.

The entire signal sequence lasted for the full 72-second window during which Big Ear was able to observe it, but has not been detected since, despite several subsequent attempts by Ehman and others. Many hypotheses have been advanced on the origin of the emission, including natural and human-made sources, but none of them adequately explains the signal.

Although the Wow! signal had no detectable modulationβ€”a technique used to transmit information over radio wavesβ€”it remains the strongest candidate for an alien radio transmission ever detected.

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πŸ”— Sex in Space

πŸ”— Spaceflight πŸ”— Sexology and sexuality

Sex in space is human sexual activity in the weightlessness of outer space. It presents difficulties for the performance of most sexual activities due to Newton's third law. According to the law, if the couple remain attached, their movements will counter each other. Consequently, their actions will not change their velocity unless they are affected by another, unattached, object. Some difficulty could occur due to drifting into other objects. If the couple have a combined velocity relative to other objects, collisions could occur. There have been suggestions that conception and pregnancy in off-Earth environments could be an issue.

As of 2009, with NASA planning long-term missions for lunar settlements with goals to explore and colonize space, the topic has taken a respected place in life sciences. Scientist Stephen Hawking publicly concluded in 2006 that possibly human survival itself will depend on successfully contending with the extreme environments of space.

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πŸ”— Erdstall

πŸ”— Europe πŸ”— Middle Ages πŸ”— Middle Ages/History

An erdstall is a type of tunnel found across Europe. They are of unknown origin but are believed to date from the Middle Ages. A variety of purposes have been theorized, including that they were used as escape routes or hiding places, but the most prominent theory is that they served a religious or spiritual purpose.

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πŸ”— Jonbar Hinge

πŸ”— Science Fiction πŸ”— Alternate History

In science-fiction criticism, a Jonbar hinge or Jonbar point is the fictional concept of a crucial point of divergence between two outcomes, especially in time-travel stories. It is sometimes referred to as a Jon Bar hinge or change-point.

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πŸ”— Accuracy and Precision

πŸ”— Mathematics πŸ”— Statistics πŸ”— Psychology

Accuracy and precision are two measures of observational error. Accuracy is how close a given set of measurements (observations or readings) are to their true value. Precision is how close the measurements are to each other.

The International Organization for Standardization (ISO) defines a related measure: trueness, "the closeness of agreement between the arithmetic mean of a large number of test results and the true or accepted reference value."

While precision is a description of random errors (a measure of statistical variability), accuracy has two different definitions:

  1. More commonly, a description of systematic errors (a measure of statistical bias of a given measure of central tendency, such as the mean). In this definition of "accuracy", the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, or neither. This concept corresponds to ISO's trueness.
  2. A combination of both precision and trueness, accounting for the two types of observational error (random and systematic), so that high accuracy requires both high precision and high trueness. This usage corresponds to ISO's definition of accuracy (trueness and precision).

πŸ”— The Mother of All Demos

πŸ”— California πŸ”— California/San Francisco Bay Area πŸ”— Computing πŸ”— Stanford University/SRI International πŸ”— Stanford University

"The Mother of All Demos" is a name retroactively applied to a landmark computer demonstration, given at the Association for Computing Machinery / Institute of Electrical and Electronics Engineers (ACM/IEEE)β€”Computer Society's Fall Joint Computer Conference in San Francisco, which was presented by Douglas Engelbart on December 9, 1968.

The live demonstration featured the introduction of a complete computer hardware and software system called the oN-Line System or, more commonly, NLS. The 90-minute presentation essentially demonstrated almost all the fundamental elements of modern personal computing: windows, hypertext, graphics, efficient navigation and command input, video conferencing, the computer mouse, word processing, dynamic file linking, revision control, and a collaborative real-time editor (collaborative work). Engelbart's presentation was the first to publicly demonstrate all of these elements in a single system. The demonstration was highly influential and spawned similar projects at Xerox PARC in the early 1970s. The underlying technologies influenced both the Apple Macintosh and Microsoft Windows graphical user interface operating systems in the 1980s and 1990s.

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πŸ”— Project Coldfeet

πŸ”— United States/U.S. Government πŸ”— United States

Project COLDFEET was a 1962 Central Intelligence Agency (CIA) operation to extract intelligence from an abandoned Soviet Arctic drifting ice station. Due to the nature of its abandonment as the result of unstable ice, the retrieval of the operatives used the Fulton surface-to-air recovery system.

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πŸ”— Sorcerer's Apprentice Syndrome

πŸ”— Computing πŸ”— Computing/Networking

Sorcerer's Apprentice Syndrome (SAS) is a network protocol flaw in the original versions of TFTP. It was named after Goethe's poem "Der Zauberlehrling" (popularized by the "Sorcerer's Apprentice" segment of the animated film Fantasia), because the details of its operation closely resemble the disaster that befalls the sorcerer's apprentice: the problem resulted in an ever-growing replication of every packet in the transfer.

The problem occurred because of a known failure mode of the internetwork which, through a mistake on the part of the TFTP protocol designers, was not taken into account when the protocol was designed; the failure mode interacted with several details of the mechanisms of TFTP to produce SAS.

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πŸ”— Wanderwort

πŸ”— Linguistics

A Wanderwort (German: [ˈvandɐˌvɔɐt], 'wandering word', plural WanderwΓΆrter; capitalized like all German nouns) is a word that has spread as a loanword among numerous languages and cultures, especially those that are far away from one another, usually in connection with trade. As such, WanderwΓΆrter are a curiosity in historical linguistics and sociolinguistics within a wider study of language contact. At a sufficient time depth, it can be very difficult to establish in which language or language family it originated and in which it was borrowed.

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