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πŸ”— Electrodynamic Tether

πŸ”— Spaceflight πŸ”— Physics

Electrodynamic tethers (EDTs) are long conducting wires, such as one deployed from a tether satellite, which can operate on electromagnetic principles as generators, by converting their kinetic energy to electrical energy, or as motors, converting electrical energy to kinetic energy. Electric potential is generated across a conductive tether by its motion through a planet's magnetic field.

A number of missions have demonstrated electrodynamic tethers in space, most notably the TSS-1, TSS-1R, and Plasma Motor Generator (PMG) experiments.

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πŸ”— Datasaurus dozen – Different datasets with the same descriptive statistics

πŸ”— Mathematics πŸ”— Statistics

The Datasaurus dozen comprises thirteen data sets that have nearly identical simple descriptive statistics to two decimal places, yet have very different distributions and appear very different when graphed. It was inspired by the smaller Anscombe's quartet that was created in

πŸ”— I, Libertine

πŸ”— Novels

I, Libertine is a literary hoax novel that began as a practical joke by late-night radio raconteur Jean Shepherd who aimed to lampoon the process of determining best-selling books. After generating substantial attention for a novel that didn't actually exist, Shepherd approved a 1956 edition of the book written mainly by Theodore Sturgeon β€” which became an actual best-seller, with all profits donated to charity.

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πŸ”— Quantum vacuum plasma thruster

πŸ”— Spaceflight πŸ”— Physics πŸ”— Alternative Views

A quantum vacuum thruster (QVT or Q-thruster) is a theoretical system hypothesized to use the same principles and equations of motion that a conventional plasma thruster would use, namely magnetohydrodynamics (MHD), to make predictions about the behavior of the propellant. However, rather than using a conventional plasma as a propellant, a QVT would interact with quantum vacuum fluctuations of the zero-point field.

The concept is controversial and generally not considered physically possible. However, if QVT systems were possible they could eliminate the need to carry propellant, being limited only by the availability of energy.

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πŸ”— Rotary Rocket

πŸ”— Companies πŸ”— Aviation πŸ”— Spaceflight πŸ”— Aviation/aircraft πŸ”— Rocketry

Rotary Rocket Company was a rocketry company that developed the Roton concept in the late 1990s as a fully reusable single-stage-to-orbit (SSTO) crewed spacecraft. The design was initially conceived by Bevin McKinney, who shared it with Gary Hudson. In 1996, Rotary Rocket Company was formed to commercialize the concept. The Roton was intended to reduce costs of launching payloads into low earth orbit by a factor of ten.

The company gathered considerable venture capital from angel investors and opened a factory headquartered in a 45,000-square-foot (4,200Β m2) facility at Mojave Air and Space Port in Mojave, California. The fuselage for their vehicles was made by Scaled Composites, at the same airport, while the company developed the novel engine design and helicopter-like landing system. A full-scale test vehicle made three hover flights in 1999, but the company exhausted its funds and closed its doors in early 2001.

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πŸ”— Mercury-Redstone 1 - The four inch flight

πŸ”— Spaceflight

Mercury-Redstone 1 (MR-1) was the first Mercury-Redstone unmanned flight test in Project Mercury and the first attempt to launch a Mercury spacecraft with the Mercury-Redstone Launch Vehicle. Intended to be an unmanned sub-orbital spaceflight, it was launched on November 21, 1960 from Cape Canaveral Air Force Station, Florida. The launch failed in a peculiar fashion which has been referred to as the "four-inch flight".

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πŸ”— Daniel W. Dobberpuhl

πŸ”— Biography πŸ”— Computing πŸ”— Biography/science and academia

Daniel "Dan" William Dobberpuhl (March 25, 1945 – October 26, 2019) was an electrical engineer in the United States who led several teams of microprocessor designers.

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πŸ”— Coulomb explosion

πŸ”— Physics

Coulombic explosions are a mechanism for transforming energy in intense electromagnetic fields into atomic motion and are thus useful for controlled destruction of relatively robust molecules. The explosions are a prominent technique in laser-based machining, and appear naturally in certain high-energy reactions.

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πŸ”— Kwangmyong, the North-Korea-Wide-Web

πŸ”— Mass surveillance πŸ”— Computing πŸ”— Korea πŸ”— Korea/North Korea

Kwangmyong (literally β€œBright Light”) is a North Korean "walled garden" national intranet service opened in 2000.

The network uses domain names under the .kp top level domain that are not accessible from the global Internet. As of 2016 the network uses IPv4 addresses reserved for private networks in the 10.0.0.0/8 range. North Koreans often find it more convenient to access sites by their IP address rather than by URL using Latin characters. Like the global Internet, the network hosts content accessible with web browsers, and provides an internal web search engine. It also provides email services and news groups.

Only foreigners and a small number of government officials/scholars/elites are allowed to use the global Internet in North Korea, making Kwangmyong the only computer network available to most North Korean citizens. It is a free service for public use.

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