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🔗 Moose: Man Out of Space Easiest

🔗 Spaceflight

MOOSE, originally an acronym for Man Out Of Space Easiest but later changed to the more professional-sounding Manned Orbital Operations Safety Equipment, was a proposed emergency "bail-out" system capable of bringing a single astronaut safely down from Earth orbit to the planet's surface. The design was proposed by General Electric in the early 1960s. The system was quite compact, weighing 200 lb (91 kg) and fitting inside a suitcase-sized container. It consisted of a small twin-nozzle rocket motor sufficient to deorbit the astronaut, a PET film bag 6 ft (1.8 m) long with a flexible 0.25 in (6.4 mm) ablative heat shield on the back, two pressurized canisters to fill it with polyurethane foam, a parachute, radio equipment and a survival kit.

The astronaut would leave the vehicle in a space suit, climb inside the plastic bag, and then fill it with foam. The bag had the shape of a blunt cone, with the astronaut embedded in its base facing the apex of the cone. The rocket pack would protrude from the bag and be used to slow the astronaut's orbital speed enough so that he would reenter Earth's atmosphere, and the foam-filled bag would act as insulation during the subsequent aerobraking. Finally, once the astronaut had descended to 30,000 ft (9.1 km) where the air was sufficiently dense, the parachute would automatically deploy and slow the astronaut's fall to 17 mph (7.6 m/s). The foam heat shield would serve a final role as cushioning when the astronaut touched down and as a flotation device should they land on water. The radio beacon would guide rescuers.

General Electric performed preliminary testing on some of the components of the MOOSE system, including flying samples of heat shield material on a Mercury mission, inflating a foam-filled bag with a human subject embedded inside, and test-dropping dummies and a human subject in MOOSE foam shields short distances. U.S. Air Force Capt. Joe Kittinger's historic freefall from a balloon at 103,000 ft (31,000 m) in August 1960 also helped demonstrate the feasibility of such extreme parachuting. However, the MOOSE system was nonetheless always intended as an extreme emergency measure when no other option for returning an astronaut to Earth existed; falling from orbit protected by nothing more than a spacesuit and a bag of foam was unlikely to ever become a particularly safe—or enticing—maneuver.

Neither NASA nor the U.S. Air Force expressed an interest in the MOOSE system, and so by the end of the 1960s the program had been quietly shelved.

Discussed on

🔗 The Tanenbaum – Torvalds Debate

🔗 Computing 🔗 Linux

The Tanenbaum–Torvalds debate was a written debate between Andrew S. Tanenbaum and Linus Torvalds, regarding the Linux kernel and kernel architecture in general. Tanenbaum, the creator of Minix, began the debate in 1992 on the Usenet discussion group comp.os.minix, arguing that microkernels are superior to monolithic kernels and therefore Linux was, even in 1992, obsolete.

The debate has sometimes been considered a flame war.

Discussed on

🔗 Naumachia

🔗 Military history 🔗 Classical Greece and Rome 🔗 Military history/Roman and Byzantine military history 🔗 Theatre 🔗 Martial arts

The naumachia (in Latin naumachia, from the Ancient Greek ναυμαχία/naumachía, literally "naval combat") in the Ancient Roman world referred to both the staging of naval battles as mass entertainment, and the basin or building in which this took place.

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🔗 Duenos Inscription

🔗 Classical Greece and Rome 🔗 Latin 🔗 Rome

The Duenos inscription is one of the earliest known Old Latin texts, variously dated from the 7th to the 5th century BC. It is inscribed on the sides of a kernos, in this case a trio of small globular vases adjoined by three clay struts. It was found by Heinrich Dressel in 1880 on the Quirinal Hill in Rome. The kernos is part of the collection of the Staatliche Museen in Berlin (inventory no. 30894,3).

The inscription is written right to left in three units, without spaces to separate words. It is difficult to translate, as some letters are hard to distinguish, particularly since they cannot always be deduced by context. The absence of spaces causes additional difficulty in assigning the letters to the respective words.

Discussed on

🔗 Ship's cat

🔗 Cats 🔗 Ships 🔗 Rodents

The ship's cat has been a common feature on many trading, exploration, and naval ships dating to ancient times. Cats have been carried on ships for many reasons, most importantly to control rodents. Vermin aboard a ship can cause damage to ropes, woodwork, and more recently, electrical wiring. Also, rodents threaten ships' stores, devour crews' foodstuff, and could cause economic damage to ships' cargo such as grain. They are also a source of disease, which is dangerous for ships that are at sea for long periods of time. Rat fleas are carriers of plague, and rats on ships were believed to be a primary vector of the Black Death.

Cats naturally attack and kill rodents, and their natural ability to adapt to new surroundings made them suitable for service on a ship. In addition, they offer companionship and a sense of home, security and camaraderie to sailors away from home.

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🔗 774–775 carbon-14 spike

🔗 Environment 🔗 Meteorology 🔗 Astronomy 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Geology 🔗 Glaciers 🔗 Solar System

The 774–775 carbon-14 spike is an observed increase of 1.2% in the concentration of carbon-14 isotope in tree rings dated to 774 or 775, which is about 20 times as high as the normal background rate of variation. It was discovered during a study of Japanese cedar trees, with the year of occurrence determined through dendrochronology. A surge in beryllium isotope 10
Be
, detected in Antarctic ice cores, has also been associated with the 774–775 event. It is known as the Miyake event or the Charlemagne event and it produced the largest and most rapid rise in carbon-14 ever recorded.

The event appears to have been global, with the same carbon-14 signal found in tree rings from Germany, Russia, the United States, Finland and New Zealand.

The signal exhibits a sharp increase of around 1.2% followed by a slow decline (see Figure 1), which is typical for an instant production of carbon-14 in the atmosphere, indicating that the event was short in duration. The globally averaged production of carbon-14 for this event is calculated as Q = 1.3×108 ± 0.2×108 atoms/cm2.

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🔗 Reply of the Zaporozhian Cossacks

🔗 Russia 🔗 Russia/demographics and ethnography of Russia 🔗 Ukraine 🔗 Visual arts 🔗 Russia/history of Russia 🔗 Russia/visual arts in Russia

Reply of the Zaporozhian Cossacks to Sultan Mehmed IV of the Ottoman Empire, also known as Cossacks of Saporog Are Drafting a Manifesto (Russian: Запорожцы пишут письмо турецкому султану), is a painting by Russian artist Ilya Repin. The 2.03 m (6 foot 7 inch) by 3.58 m (11 foot 9 inch) canvas was started in 1880 and finished in 1891. Repin recorded the years of work along the lower edge of the canvas. Alexander III bought the painting for 35,000 rubles, at the time the greatest sum ever paid for a Russian painting. Since then, the canvas has been exhibited in the State Russian Museum in Saint Petersburg.

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🔗 Homotopy Type Theory

🔗 Computer science 🔗 Mathematics

In mathematical logic and computer science, homotopy type theory (HoTT ) refers to various lines of development of intuitionistic type theory, based on the interpretation of types as objects to which the intuition of (abstract) homotopy theory applies.

This includes, among other lines of work, the construction of homotopical and higher-categorical models for such type theories; the use of type theory as a logic (or internal language) for abstract homotopy theory and higher category theory; the development of mathematics within a type-theoretic foundation (including both previously existing mathematics and new mathematics that homotopical types make possible); and the formalization of each of these in computer proof assistants.

There is a large overlap between the work referred to as homotopy type theory, and as the univalent foundations project. Although neither is precisely delineated, and the terms are sometimes used interchangeably, the choice of usage also sometimes corresponds to differences in viewpoint and emphasis. As such, this article may not represent the views of all researchers in the fields equally. This kind of variability is unavoidable when a field is in rapid flux.

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🔗 Open Cola

🔗 Computing 🔗 Food and drink 🔗 Brands 🔗 Food and drink/Beverages

OpenCola is a brand of open-source cola, where the instructions for making it are freely available and modifiable. Anybody can make the drink, and anyone can modify and improve on the recipe. It was launched in 2001 by free software P2P company Opencola, to promote their open-source software concept.

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🔗 Islands in lakes on islands in lakes on islands

🔗 Islands 🔗 Lakes

A recursive island or lake is an island or lake that is itself within an island or lake.