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🔗 Military history 🔗 Military history/Maritime warfare 🔗 Ships 🔗 Military history/Russian, Soviet and CIS military history

K-219 was a Project 667A Navaga-class ballistic missile submarine (NATO reporting name Yankee I) of the Soviet Navy. It carried 16 R-27U liquid-fuel missiles powered by UDMH with nitrogen tetroxide (NTO), and equipped with either 32 or 48 nuclear warheads.K-219 was involved in what has become one of the most controversial submarine incidents during the Cold War on Friday 3 October 1986. The 15-year-old vessel, which was on an otherwise routine Cold War nuclear deterrence patrol in the North Atlantic 1,090 kilometres (680 mi) northeast of Bermuda, suffered an explosion and fire in a missile tube. While underway submerged the seal in a missile hatch cover failed, allowing high-pressure seawater to enter the missile tube and owing to the pressure differential rupture the missile fuel tanks, allowing missile's liquid fuel to mix and ultimately combust. Though there was no official announcement, the Soviet Union claimed the leak was caused by a collision with the submarine USS Augusta. Although Augusta was operating within the area, both the United States Navy and the commander of K-219, Captain Second Rank Igor Britanov, deny that a collision took place.

The incident was novelized in the book Hostile Waters, which reconstructed the incident from descriptions by the survivors, ships' logs, the official investigations, and participants both ashore and afloat from the Soviet and the American sides.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Cold War

Blue Peacock, renamed from Blue Bunny and originally Brown Bunny, was a British tactical nuclear weapon project in the 1950s.

The project's goal was to store a number of ten-kiloton nuclear mines in Germany, to be placed on the North German Plain and, in the event of Soviet invasion from the east, detonated by wire or an eight-day timer to:

... not only destroy facilities and installations over a large area, but ... deny occupation of the area to an enemy for an appreciable time due to contamination ...

🔗 Skepticism 🔗 Alternative Views 🔗 Archaeology 🔗 Paranormal

An out-of-place artifact (OOPArt) is an artifact of historical, archaeological, or paleontological interest found in an unusual context, which challenges conventional historical chronology by its presence in that context. Such artifacts may appear "too advanced" for the technology known to have existed at the time, or may suggest human presence at a time before humans are known to have existed. Other examples may suggest contact between different cultures that is hard to account for with conventional historical understanding.

The term is used in fringe science such as cryptozoology, as well as by proponents of ancient astronaut theories, young Earth creationists, and paranormal enthusiasts. It can describe a wide variety of objects, from anomalies studied by mainstream science to pseudoarchaeology far outside the mainstream to objects that have been shown to be hoaxes or to have mundane explanations.

Critics argue that most purported OOPArts which are not hoaxes are the result of mistaken interpretation and wishful thinking, such as a mistaken belief that a particular culture could not have created an artifact or technology due to a lack of knowledge or materials. In some cases, the uncertainty results from inaccurate descriptions. For example, the Wolfsegg Iron was said to be a perfect cube, but in fact it is not; the Klerksdorp spheres were said to be perfect spheres, but they are not. The Iron pillar of Delhi was said to be "rust proof", but it has some rust near its base; its relative resistance to corrosion is due to slag inclusions left over from the manufacturing conditions and environmental factors.

Supporters regard OOPArts as evidence that mainstream science is overlooking huge areas of knowledge, either willfully or through ignorance. Many writers or researchers who question conventional views of human history have used purported OOPArts in attempts to bolster their arguments. Creation science often relies on allegedly anomalous finds in the archaeological record to challenge scientific chronologies and models of human evolution. Claimed OOPArts have been used to support religious descriptions of prehistory, ancient astronaut theories, and the notion of vanished civilizations that possessed knowledge or technology more advanced than that known in modern times.

🔗 Chess

The mutilated chessboard problem is a tiling puzzle proposed by philosopher Max Black in his book Critical Thinking (1946). It was later discussed by Solomon W. Golomb (1954), Gamow & Stern (1958) and by Martin Gardner in his Scientific American column "Mathematical Games". The problem is as follows:

Suppose a standard 8×8 chessboard has two diagonally opposite corners removed, leaving 62 squares. Is it possible to place 31 dominoes of size 2×1 so as to cover all of these squares?

Most considerations of this problem in literature provide solutions "in the conceptual sense" without proofs. John McCarthy proposed it as a hard problem for automated proof systems. In fact, its solution using the resolution system of inference is exponentially hard.

🔗 Physics 🔗 Geology

A fossil natural nuclear fission reactor is a uranium deposit where self-sustaining nuclear chain reactions have occurred. This can be examined by analysis of isotope ratios. The conditions under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kazuo Kuroda. The phenomenon was discovered in 1972 in Oklo, Gabon by French physicist Francis Perrin under conditions very similar to what was predicted.

Oklo is the only known location for this in the world and consists of 16 sites at which self-sustaining nuclear fission reactions are thought to have taken place approximately 1.7 billion years ago, and ran for a few hundred thousand years, averaging probably less than 100 kW of thermal power during that time.

🔗 Computing 🔗 Computing/Computer science

In computer programming, a rope, or cord, is a data structure composed of smaller strings that is used to efficiently store and manipulate a very long string. For example, a text editing program may use a rope to represent the text being edited, so that operations such as insertion, deletion, and random access can be done efficiently.

🔗 International relations 🔗 Espionage 🔗 Soviet Union 🔗 Russia 🔗 Russia/history of Russia 🔗 English Language

In political jargon, a useful idiot is a derogatory term for a person perceived as propagandizing for a cause without fully comprehending the cause's goals, and who is cynically used by the cause's leaders. The term was originally used during the Cold War to describe non-communists regarded as susceptible to communist propaganda and manipulation. The term has often been attributed to Vladimir Lenin, but this attribution is unsubstantiated.

🔗 Physics

The Large Electron–Positron Collider (LEP) was one of the largest particle accelerators ever constructed.

It was built at CERN, a multi-national centre for research in nuclear and particle physics near Geneva, Switzerland. LEP collided electrons with positrons at energies that reached 209 GeV. It was a circular collider with a circumference of 27 kilometres built in a tunnel roughly 100 m (300 ft) underground and passing through Switzerland and France. LEP was used from 1989 until 2000. Around 2001 it was dismantled to make way for the Large Hadron Collider, which re-used the LEP tunnel. To date, LEP is the most powerful accelerator of leptons ever built.

🔗 United States 🔗 Internet 🔗 Law 🔗 Freedom of speech 🔗 Law Enforcement 🔗 United States/FBI

A warrant canary is a method by which a communications service provider aims to inform its users that the provider has been served with a government subpoena despite legal prohibitions on revealing the existence of the subpoena. The warrant canary typically informs users that there has not been a court-issued subpoena as of a particular date. If the canary is not updated for the period specified by the host or if the warning is removed, users are to assume that the host has been served with such a subpoena. The intention is to allow the provider to warn users of the existence of a subpoena passively, without technically violating the court order not to do so.

Some subpoenas, such as those covered under 18 U.S.C. §2709(c) of the USA Patriot Act, provide criminal penalties for disclosing the existence of the subpoena to any third party, including the service provider's users.

National Security Letters (NSL) originated in the 1986 Electronic Communications Privacy Act and originally targeted those suspected of being agents of a foreign power. Targeting agents of a foreign power was revised in 2001 under the Patriot Act to allow NSLs to target those who may have information deemed relevant to both counterintelligence activities directed against the United States and terrorism. The idea of using negative pronouncements to thwart the nondisclosure requirements of court orders and served secret warrants was first proposed by Steven Schear on the cypherpunks mailing list, mainly to uncover targeted individuals at ISPs. It was also suggested for and used by public libraries in 2002 in response to the USA Patriot Act, which could have forced librarians to disclose the circulation history of library patrons.