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🔗 Maps 🔗 Photography

The Boston Camera, also known as Pie Face and officially classified as the K-42 Camera Model, was a prototype airborne photo reconnaissance camera manufactured for the United States Air Force by Boston University in 1951 and tested on the Convair B-36 and the C-97 Stratofreighter. The model carried on the first ERB-36D (44-92088) had a 6,096-millimetre (240.0 in) focal length, which was achieved using a series of lenses and mirrors. The lens had an f/8 stop and used a 1/400 second shutter speed, and could photograph a golf ball from an altitude of 45,000 feet (14,000 m) feet. The camera used 18-by-36-inch (46 by 91 cm) negatives. The camera was installed aboard Boeing C-97A 49-2592 (not an "RC-97" or "EC-97" as often widely quoted) which was used operationally by the 7405th Support Squadron based at Wiesbaden, West Germany between 1952 and 1962. It was given to the Air Force Museum in 1964, along with a contact print of a golf ball on a course.

In the words of CIA historian Dino Brugioni:

The lens was designed in 1947 by Dr. James Baker for installation in a camera designed by the Boston University Optical Research Laboratory. The camera weighed about three tons, and eight hundred pounds of lead shot were required to balance it. Supposedly, it was first installed and test-flown in an RB-36, then installed as a left-looking oblique camera in an RC-97. The first photo Arthur Lundahl and I saw from this project was of New York City. The aircraft was seventy-two miles away, and yet we could see people in Central Park.

The Boston Camera was plagued with problems that caused it to vibrate and produce smearing on the newspaper-sized negative, so that photo interpreters would see several smeared frames along with several clear ones. It is currently displayed at the National Museum of the US Air Force in Dayton, Ohio.

From the display placard:

This camera, manufactured for the US Air Force by Boston University in 1951, is the largest aerial camera ever built. It was installed in an RB-36D in 1954 and tested for about a year. Later it was used in a C-97 aircraft flying along the air corridor through communist East Germany to Berlin, but a 10,000 ft (3,000 m) altitude restriction imposed by the communists made the camera less useful than at a higher altitude. It was also used on reconnaissance missions along the borders of Eastern European nations. The camera made an 18 x 36 inch negative and was so powerful a photo interpreter could detect a golf ball from an altitude of 45,000 feet (14,000 m). Dr. James Baker of Harvard University designed the camera.

Technical Notes:

Shutter Speed: 1/400 sec

Weight: 6,500 lbs (3 metric ton) (camera and aircraft mount)

🔗 Death 🔗 Greece 🔗 Paranormal

The term Drosoulites (Greek: Δροσουλίτες) refers to a long procession of visions, seen by residents around Frangokastello castle in Sfakia region of Crete (Greece). The phenomenon is rumored to be visible every year, on the anniversary of the Battle of Frangokastello or even in early June near a small village in southern Crete.

The visions, as described by witnesses, consist of a group of human-like shadows dressed in black, walking or riding, armed with weapons, moving from the monastery of Agios Charalambos and advancing towards the old fort, Frangokastello, a 14th-century Venetian fortification. Legend has it that this group of people are Greek fighters that died during the Battle of Frangokastello (17 May 1828) and since then they appear as supernatural beings in the area.

The ghost army is led by Hatzimichalis Dalianis, from Delvinaki in Epirus, the chief of the Greek men, 350 of whom were lost, in the battle. The army took refuge in the fort during the Greek War of Independence against the Turks, where they were killed after a seven-day siege.

The local people named them Drosoulites ("dew shadows") due to the time of day that the phenomenon takes place. The phenomenon is observed when the sea is calm and the atmosphere is moist and before the sun rises too high in the sky. It usually lasts about 10 minutes.

The shadows are visible from the valley at a distance of 1000 m. Many have tried to explain the phenomenon scientifically, and at one time it was explained as a mirage from the coast of North Africa, but still there is no accepted consensus. On the other hand, another, occult, interpretation implies the existence of a psychic phenomenon, clairvoyance, seen in some countries like Britain and Germany, also regarding ghost armies. The appearance of the Drosoulites is documented over the ages. In 1890 a transient Turkish army took the images for rebels and fled away. Even during the Second World War, a German patrol is said to have opened fire on the visions.

🔗 Mathematics 🔗 Percussion

To hear the shape of a drum is to infer information about the shape of the drumhead from the sound it makes, i.e., from the list of overtones, via the use of mathematical theory.

"Can One Hear the Shape of a Drum?" is the title of a 1966 article by Mark Kac in the American Mathematical Monthly which made the question famous, though this particular phrasing originates with Lipman Bers. Similar questions can be traced back all the way to Hermann Weyl . For his paper, Kac was given the Lester R. Ford Award in 1967 and the Chauvenet Prize in 1968.

The frequencies at which a drumhead can vibrate depend on its shape. The Helmholtz equation calculates the frequencies if the shape is known. These frequencies are the eigenvalues of the Laplacian in the space. A central question is whether the shape can be predicted if the frequencies are known; for example, whether a circle-shaped triangle can be recognized in this way. Kac admitted he did not know if it was possible for two different shapes to yield the same set of frequencies. The question of whether the frequencies determine the shape was finally answered in the negative in the early 1990s by Gordon, Webb and Wolpert.

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

Red mercury is purportedly a substance of uncertain composition used in the creation of nuclear weapons, as well as other weapons systems. Because of the great secrecy surrounding the development and manufacture of nuclear weapons, there is no proof that red mercury exists. However, all samples of alleged "red mercury" analyzed in the public literature have proven to be well-known, common red substances of no interest to weapons makers.

Red mercury is therefore considered a hoax, perpetrated by con artists who sought to take advantage of gullible buyers on the black market for arms. There have been reports of "red mercury" on the international black markets since 1979, but the hoax seems to have been most common in the early 1990s, with very high asking prices.

🔗 Military history 🔗 Heraldry and vexillology 🔗 Catholicism 🔗 Military history/Crusades 🔗 Military history/Medieval warfare 🔗 Countries 🔗 Former countries 🔗 Military history/National militaries 🔗 Malta 🔗 Orders, decorations, and medals

The Sovereign Military Order of Malta (SMOM), officially the Sovereign Military Hospitaller Order of Saint John of Jerusalem, of Rhodes and of Malta (Italian: Sovrano Militare Ordine Ospedaliero di San Giovanni di Gerusalemme di Rodi e di Malta; Latin: Supremus Militaris Ordo Hospitalarius Sancti Ioannis Hierosolymitani Rhodiensis et Melitensis), commonly known as the Order of Malta, Malta Order or Knights of Malta, is a Catholic lay religious order, traditionally of military, chivalric and noble nature. Though it possesses no territory, the order is a sovereign entity of international law and maintains diplomatic relations with many countries.

SMOM claims continuity with the Knights Hospitaller, a chivalric order that was founded c. 1099 by the Blessed Gerard in the Kingdom of Jerusalem. The order is led by an elected Prince and Grand Master. Its motto is Tuitio fidei et obsequium pauperum ('defence of the faith and assistance to the poor'). The order venerates the Virgin Mary as its patroness, under the title of Our Lady of Philermos. Its modern-day role is largely focused on providing humanitarian assistance and assisting with international humanitarian relations, for which purpose it has had permanent observer status at the United Nations General Assembly since 1994.

🔗 Computing 🔗 Computing/Early computers

The TX-0, for Transistorized Experimental computer zero, but affectionately referred to as tixo (pronounced "tix oh"), was an early fully transistorized computer and contained a then-huge 64K of 18-bit words of magnetic core memory. Construction of the TX-0 began in 1955 and ended in 1956. It was used continually through the 1960s at MIT. The TX-0 incorporated around 3600 Philco high-frequency surface-barrier transistors, the first transistor suitable for high-speed computers. The TX-0 and its direct descendant, the original PDP-1, were platforms for pioneering computer research and the development of what would later be called computer "hacker" culture.

🔗 Computing

Simula is the name of two simulation programming languages, Simula I and Simula 67, developed in the 1960s at the Norwegian Computing Center in Oslo, by Ole-Johan Dahl and Kristen Nygaard. Syntactically, it is a fairly faithful superset of ALGOL 60, also influenced by the design of Simscript.

Simula 67 introduced objects, classes, inheritance and subclasses, virtual procedures, coroutines, and discrete event simulation, and features garbage collection. Also other forms of subtyping (besides inheriting subclasses) were introduced in Simula derivatives.

Simula is considered the first object-oriented programming language. As its name suggests, the first Simula version by 1962 was designed for doing simulations; Simula 67 though was designed to be a general-purpose programming language and provided the framework for many of the features of object-oriented languages today.

Simula has been used in a wide range of applications such as simulating very-large-scale integration (VLSI) designs, process modeling, communication protocols, algorithms, and other applications such as typesetting, computer graphics, and education. The influence of Simula is often understated, and Simula-type objects are reimplemented in C++, Object Pascal, Java, C#, and many other languages. Computer scientists such as Bjarne Stroustrup, creator of C++, and James Gosling, creator of Java, have acknowledged Simula as a major influence.

🔗 Aviation

Balloonomania was a strong public interest or fad in balloons that originated in France in the late 18th century and continued into the 19th century, during the advent of balloon flights. The interest began with the first flights of the Montgolfier brothers in 1783 (in a balloon inflated with hot air). Soon afterwards Jacques Alexandre César Charles flew another type of balloon (inflated with hydrogen) and both types of balloon were in use from then on. The fad quickly spread in France and across the channel in England.

🔗 Mass surveillance 🔗 Computing 🔗 Internet culture 🔗 Philosophy 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Numismatics 🔗 Sociology 🔗 Numismatics/Cryptocurrency 🔗 Computing/Computer Security 🔗 Philosophy/Anarchism 🔗 Anarchism

Crypto-anarchism (or crypto-anarchy) is a political ideology focusing on protection of privacy, political freedom and economic freedom, the adherents of which use cryptographic software for confidentiality and security while sending and receiving information over computer networks.

By using cryptographic software, the association between the identity of a certain user or organization and the pseudonym they use is made difficult to find, unless the user reveals the association. It is difficult to say which country's laws will be ignored, as even the location of a certain participant is unknown. However, participants may in theory voluntarily create new laws using smart contracts or, if the user is pseudonymous, depend on online reputation.

🔗 Computing 🔗 Computing/Software 🔗 Numismatics 🔗 Numismatics/Cryptocurrency 🔗 Cryptocurrency

Gridcoin (ticker: GRC) is an open source cryptocurrency which securely rewards volunteer computing performed on the BOINC, a distributed computing platform that is home to over 30 science projects spanning a range of scientific disciplines.

Gridcoin attempts to address and ease the environmental energy impact of cryptocurrency mining through its proof-of-research and proof-of-stake protocols, as compared to the proof of work system used by Bitcoin.