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π Nuclear Engine for Rocket Vehicle Application (Nerva)
The Nuclear Engine for Rocket Vehicle Application (NERVA) was a nuclear thermal rocket engine development program that ran for roughly two decades. Its principal objective was to "establish a technology base for nuclear rocket engine systems to be utilized in the design and development of propulsion systems for space mission application". It was a joint effort of the Atomic Energy Commission (AEC) and the National Aeronautics and Space Administration (NASA), and was managed by the Space Nuclear Propulsion Office (SNPO) until the program ended in January 1973. SNPO was led by NASA's Harold Finger and AEC's Milton Klein.
NERVA had its origins in Project Rover, an AEC research project at the Los Alamos Scientific Laboratory (LASL) with the initial aim of providing a nuclear-powered upper stage for the United States Air Force intercontinental ballistic missiles. Nuclear thermal rocket engines promised to be more efficient than chemical ones. After the formation of NASA in 1958, Project Rover was continued as a civilian project and was reoriented to producing a nuclear powered upper stage for NASA's Saturn V Moon rocket. Reactors were tested at very low power before being shipped to Jackass Flats in the Nevada Test Site. While LASL concentrated on reactor development, NASA built and tested complete rocket engines.
The AEC, SNPO, and NASA considered NERVA a highly successful program in that it met or exceeded its program goals. It demonstrated that nuclear thermal rocket engines were a feasible and reliable tool for space exploration, and at the end of 1968 SNPO deemed that the latest NERVA engine, the XE, met the requirements for a human mission to Mars. It had strong political support from Senators Clinton P. Anderson and Margaret Chase Smith but was cancelled by President Richard Nixon in 1973. Although NERVA engines were built and tested as much as possible with flight-certified components and the engine was deemed ready for integration into a spacecraft, they never flew in space.
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- "Nuclear Engine for Rocket Vehicle Application (Nerva)" | 2023-09-28 | 28 Upvotes 9 Comments
π Panspermia
Panspermia (from Ancient Greek ΟαΎΆΞ½ (pan), meaning 'all', and ΟΟΞΟΞΌΞ± (sperma), meaning 'seed') is the hypothesis that life exists throughout the Universe, distributed by space dust, meteoroids, asteroids, comets, planetoids, and also by spacecraft carrying unintended contamination by microorganisms. Distribution may have occurred spanning galaxies, and so may not be restricted to the limited scale of solar systems.
Panspermia hypotheses propose (for example) that microscopic life-forms that can survive the effects of space (such as extremophiles) can become trapped in debris ejected into space after collisions between planets and small Solar System bodies that harbor life. Some organisms may travel dormant for an extended amount of time before colliding randomly with other planets or intermingling with protoplanetary disks. Under certain ideal impact circumstances (into a body of water, for example), and ideal conditions on a new planet's surfaces, it is possible that the surviving organisms could become active and begin to colonize their new environment. At least one report finds that endospores from a type of Bacillus bacteria found in Morocco can survive being heated to 420Β Β°C (788Β Β°F), making the argument for Panspermia even stronger. Panspermia studies concentrate not on how life began, but on methods that may distribute it in the Universe.
Pseudo-panspermia (sometimes called "soft panspermia" or "molecular panspermia") argues that the pre-biotic organic building-blocks of life originated in space, became incorporated in the solar nebula from which planets condensed, and were furtherβand continuouslyβdistributed to planetary surfaces where life then emerged (abiogenesis). From the early 1970s, it started to become evident that interstellar dust included a large component of organic molecules. Interstellar molecules are formed by chemical reactions within very sparse interstellar or circumstellar clouds of dust and gas. The dust plays a critical role in shielding the molecules from the ionizing effect of ultraviolet radiation emitted by stars.
The chemistry leading to life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10 to 17 million years old. Though the presence of life is confirmed only on the Earth, some scientists think that extraterrestrial life is not only plausible, but probable or inevitable. Probes and instruments have started examining other planets and moons in the Solar System and in other planetary systems for evidence of having once supported simple life, and projects such as SETI attempt to detect radio transmissions from possible extraterrestrial civilizations.
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- "Panspermia" | 2018-10-13 | 73 Upvotes 44 Comments
π Electrochemical RAM
Electrochemical Random-Access Memory (ECRAM) is a type of non-volatile memory (NVM) with multiple levels per cell (MLC) designed for deep learning analog acceleration. An ECRAM cell is a three-terminal device composed of a conductive channel, an insulating electrolyte, an ionic reservoir, and metal contacts. The resistance of the channel is modulated by ionic exchange at the interface between the channel and the electrolyte upon application of an electric field. The charge-transfer process allows both for state retention in the absence of applied power, and for programming of multiple distinct levels, both differentiating ECRAM operation from that of a field-effect transistor (FET). The write operation is deterministic and can result in symmetrical potentiation and depression, making ECRAM arrays attractive for acting as artificial synaptic weights in physical implementations of artificial neural networks (ANN). The technological challenges include open circuit potential (OCP) and semiconductor foundry compatibility associated with energy materials. Universities, government laboratories, and corporate research teams have contributed to the development of ECRAM for analog computing. Notably, Sandia National Laboratories designed a lithium-based cell inspired by solid-state battery materials, Stanford University built an organic proton-based cell, and International Business Machines (IBM) demonstrated in-memory selector-free parallel programming for a logistic regression task in an array of metal-oxide ECRAM designed for insertion in the back end of line (BEOL). In 2022, researchers at Massachusetts Institute of Technology built an inorganic, CMOS-compatible protonic technology that achieved near-ideal modulation characteristics using nanosecond fast pulses
π Democracy Distribution of the World
The Democracy Index is an index compiled by the Economist Intelligence Unit (EIU), a UK-based company. It intends to measure the state of democracy in 167 countries, of which 166 are sovereign states and 164 are UN member states.
The index was first published in 2006, with updates for 2008, 2010 and later years. The index is based on 60 indicators grouped in five different categories, measuring pluralism, civil liberties and political culture. In addition to a numeric score and a ranking, the index categorises each country in one of four regime types: full democracies, flawed democracies, hybrid regimes and authoritarian regimes.
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- "Democracy Distribution of the World" | 2011-05-15 | 31 Upvotes 20 Comments
π Evercookie
Evercookie is a JavaScript-based application created by Samy Kamkar that produces zombie cookies in a web browser that are intentionally difficult to delete. In 2013, a top-secret NSA document was leaked by Edward Snowden, citing Evercookie as a method of tracking Tor users.
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- "Evercookie" | 2011-04-05 | 75 Upvotes 17 Comments
π List of photographs considered the most important
This is a list of photographs considered the most important in surveys where authoritative sources review the history of the medium not limited by time period, region, genre, topic, or other specific criteria. These images may be referred to as the most important, most iconic, or most influentialβbut they are all considered key images in the history of photography.
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- "List of photographs considered the most important" | 2023-09-12 | 11 Upvotes 3 Comments
π Energy Slave
An energy slave is that quantity of energy (ability to do work) which, when used to construct and drive non-human infrastructure (machines, roads, power grids, fuel, draft animals, wind-driven pumps, etc.) replaces a unit of human labor (actual work). An energy slave does the work of a person, through the consumption of energy in the non-human infrastructure.
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- "Energy Slave" | 2020-06-12 | 11 Upvotes 5 Comments
π Stu Ungar
Stuart Errol Ungar (September 8, 1953 β November 22, 1998) was an American professional poker, blackjack, and gin rummy player, widely regarded to have been the greatest Texas hold 'em and gin player of all time.
He is one of two people in poker history to have won the World Series of Poker Main Event three times. He is the only person to win Amarillo Slim's Super Bowl of Poker three times, the world's second most prestigious poker title during its time. He is one of four players in poker history to win consecutive titles in the WSOP Main Event, along with Johnny Moss, Doyle Brunson and Johnny Chan.
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- "Stu Ungar" | 2019-09-30 | 76 Upvotes 44 Comments
π Manosphere
The manosphere is a varied collection of websites, blogs, and online forums promoting masculinity, misogyny, and opposition to feminism. Communities within the manosphere include men's rights activists (MRAs), incels (involuntary celibates), Men Going Their Own Way (MGTOW), pick-up artists (PUA), and fathers' rights groups. While the specifics of each group's beliefs sometimes conflict, they are generally united in the belief that society is biased against men due to the influence of feminism, and that feminists promote misandry (hatred of men). Acceptance of these ideas is described as "taking the red pill", a metaphor borrowed from the film The Matrix.
The manosphere overlaps with the far-right and alt-right communities. It has also been associated with online harassment and has been implicated in radicalizing men into misogynist beliefs and the glorification of violence against women. Some sources have associated manosphere-based radicalization with mass shootings motivated by misogyny. The manosphere received significant media coverage following the 2014 Isla Vista killings in California, the 2015 Umpqua Community College shooting in Oregon, and the 2018 Toronto van attack, as well as the online harassment campaign against women in the video game industry known as GamerGate.
Major figures within the movement include various social media influencers, including Andrew Tate, Amrou "Myron Gaines" Fudl, Adin Ross, Roosh V, Carl Benjamin and Jordan Peterson.
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- "Manosphere" | 2025-06-01 | 12 Upvotes 1 Comments
π StretchText
StretchText is a hypertext feature that has not gained mass adoption in systems like the World Wide Web, but gives more control to the reader in determining what level of detail to read at. Authors write content to several levels of detail in a work.
StretchText is similar to outlining, however instead of drilling down lists to greater detail, the current node is replaced with a newer node. This βstretchingβ to increase the amount of writing, or contracting to decrease it gives the feature its name. This is analogous to zooming in to get more detail.
Ted Nelson coined the term c.β1967.
Conceptually, StretchText is similar to existing hypertexts system where a link provides a more descriptive or exhaustive explanation of something, but there is a key difference between a link and a piece of StretchText. A link completely replaces the current piece of hypertext with the destination, whereas StretchText expands or contracts the content in place. Thus, the existing hypertext serves as context.
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- "StretchText" | 2022-07-23 | 111 Upvotes 38 Comments