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The Odeillo solar furnace is the world's largest solar furnace. It is situated in Font-Romeu-Odeillo-Via, in the department of Pyrénées-Orientales, in south of France. It is 54 metres (177 ft) high and 48 metres (157 ft) wide, and includes 63 heliostats. It was built between 1962 and 1968, and started operating in 1969, and has a power of one megawatt.

It serves as a science research site studying materials at very high temperatures.

🔗 Aviation 🔗 Military history 🔗 Military history/Military aviation 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Aviation/aircraft 🔗 Aviation/aircraft engine

The Aircraft Nuclear Propulsion (ANP) program and the preceding Nuclear Energy for the Propulsion of Aircraft (NEPA) project worked to develop a nuclear propulsion system for aircraft. The United States Army Air Forces initiated Project NEPA on May 28, 1946. NEPA operated until May 1951, when the project was transferred to the joint Atomic Energy Commission (AEC)/USAF ANP. The USAF pursued two different systems for nuclear-powered jet engines, the Direct Air Cycle concept, which was developed by General Electric, and Indirect Air Cycle, which was assigned to Pratt & Whitney. The program was intended to develop and test the Convair X-6, but was cancelled in 1961 before that aircraft was built. The total cost of the program from 1946 to 1961 was about $1 billion.

🔗 Canada 🔗 Finance & Investment 🔗 Marketing & Advertising 🔗 Numismatics 🔗 Automobiles 🔗 Retailing

Canadian Tire money, officially Canadian Tire 'money' or CTM, is a loyalty program operated by the Canadian retail chain Canadian Tire Corporation (CTC). It consists of both paper coupons introduced in 1958 and used in Canadian Tire stores as scrip, and since 2012 in a digital form introduced as Canadian Tire Money Advantage, rebranded in 2018 as Triangle Rewards. Both forms of the loyalty program remain current as of December 2022. Canadian Tire Money has been noted as the most successful loyalty program in Canadian retail history.

Canadian Tire Money is denominated in Canadian dollars. It is earned based on the pre-tax amount of a purchase, excluding labour and shop supplies costs. The initial rate earned was 5% of the eligible purchase price, but it was lowered to 3%, then to 1.4% and now is 0.4%.

When used to pay for merchandise, CTM is considered to be a cash equivalent and may be used to pay for any part of a purchase, including sales taxes. CTM cannot be exchanged for real Canadian currency.

🔗 Medicine 🔗 Dogs 🔗 Psychology 🔗 Anthropology 🔗 India 🔗 Medicine/Psychiatry

Puppy pregnancy syndrome (PPS) is a psychosomatic illness in humans brought on by mass hysteria.

The syndrome is thought to be localized in villages in several states of India, including West Bengal, Assam, Bihar, Jharkhand, Orissa, and Chhattisgarh, and has been reported by tens of thousands of individuals. It is far more prevalent in areas with little access to education.

People suffering from PPS believe that shortly after being bitten by a dog, puppies are conceived within their abdomen. This is said to be especially likely if the dog is sexually excited at the time of the attack. Victims are said to bark like dogs and have reported being able to see the puppies inside them when looking at water or hear them growling in their abdomen. It is believed that the victims will eventually die – especially men, who will give birth to their puppies through the penis.

Witch doctors offer oral cures, which they claim will dissolve the puppies, allowing them to pass through the digestive system and be excreted "without the knowledge of the patient".

Doctors in India have tried to educate the public about the dangers of believing in this condition. Most sufferers are referred to psychiatric services, but in some instances patients fail to take anti-rabies medication before symptom onset, thinking that they are pregnant with a puppy and that folk medicine will cure them. This misbelief is further compounded by witch doctors who state that their medicine will fail if sufferers seek standard treatment.

Some psychiatrists believe that PPS meets the criteria for a culture-bound disorder.

🔗 Physics

The Magdeburg hemispheres are a pair of large copper hemispheres, with mating rims. They were used to demonstrate the power of atmospheric pressure. When the rims were sealed with grease and the air was pumped out, the sphere contained a vacuum and could not be pulled apart by teams of horses. The Magdeburg hemispheres were invented by German scientist and mayor of Magdeburg, Otto von Guericke, to demonstrate the air pump that he had invented, and the concept of atmospheric pressure. The first artificial vacuum had been produced a few years earlier by Evangelista Torricelli, and had inspired Guericke to design the world's first vacuum pump, which consisted of a piston and cylinder with one-way flap valves. The hemispheres became popular in physics lectures as an illustration of the strength of air pressure, and are still used in education. A pair of the original hemispheres are preserved in the Deutsches Museum in Munich.

🔗 United States 🔗 African diaspora 🔗 Holidays 🔗 United States/Texas 🔗 United States/U.S. history 🔗 Black Lives Matter 🔗 Project-independent assessment 🔗 Houston

Juneteenth is a federal holiday in the United States. It is celebrated annually on June 19 to commemorate the ending of slavery in the United States. The holiday's name, first used in the 1890s, is a portmanteau of the words "June" and "nineteenth", referring to June 19, 1865, the day when Major General Gordon Granger ordered the final enforcement of the Emancipation Proclamation in Texas at the end of the American Civil War. In the Civil War period, slavery came to an end in various areas of the United States at different times. Many enslaved Southerners escaped, demanded wages, stopped work, or took up arms against the Confederacy of slave states. In January 1865, Congress finally proposed the Thirteenth Amendment to the United States Constitution for the national abolition of slavery. By June 1865, almost all enslaved persons had been freed by the victorious Union Army or by state abolition laws. When the national abolition amendment was ratified in December, the remaining enslaved people in Delaware and in Kentucky were freed.

Early Juneteenth celebrations date back to 1866, at first involving church-centered community gatherings in Texas. They spread across the South among newly freed African-Americans and their descendants and became more commercialized in the 1920s and 1930s, often centering on a food festival. Participants in the Great Migration brought these celebrations to the rest of the country. During the Civil Rights Movement of the 1960s, these celebrations were eclipsed by the nonviolent determination to achieve civil rights, but grew in popularity again in the 1970s with a focus on African-American freedom and African-American arts. Beginning with Texas by proclamation in 1938, and by legislation in 1979, every U.S. state and the District of Columbia has formally recognized the holiday in some way.

Juneteenth is also celebrated by the Mascogos, descendants of Black Seminoles who escaped from slavery in 1852 and settled in Coahuila, Mexico.

The day was recognized as a federal holiday in 2021, when the 117th U.S. Congress enacted and President Joe Biden signed the Juneteenth National Independence Day Act into law. Juneteenth became the first new federal holiday since Martin Luther King Jr. Day was adopted in 1983.

🔗 Computing 🔗 Classical Greece and Rome 🔗 Greece 🔗 Astronomy 🔗 History of Science 🔗 Alternative Views 🔗 Time

The Antikythera mechanism (, ) is an ancient hand powered Greek analogue computer which has also been described as the first example of such device used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games.

This artefact was retrieved from the sea in 1901, and identified on 17 May 1902 as containing a gear by archaeologist Valerios Stais, among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera. The instrument is believed to have been designed and constructed by Greek scientists and has been variously dated to about 87 BC, or between 150 and 100 BC, or to 205 BC, or to within a generation before the shipwreck, which has been dated to approximately 70–60 BC.

The device, housed in the remains of a 34 cm × 18 cm × 9 cm (13.4 in × 7.1 in × 3.5 in) wooden box, was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is approximately 14 centimetres (5.5 in) in diameter and originally had 223 teeth.

It is a complex clockwork mechanism composed of at least 30 meshing bronze gears. A team led by Mike Edmunds and Tony Freeth at Cardiff University used modern computer x-ray tomography and high resolution surface scanning to image inside fragments of the crust-encased mechanism and read the faintest inscriptions that once covered the outer casing of the machine.

Detailed imaging of the mechanism suggests that it had 37 gear wheels enabling it to follow the movements of the Moon and the Sun through the zodiac, to predict eclipses and even to model the irregular orbit of the Moon, where the Moon's velocity is higher in its perigee than in its apogee. This motion was studied in the 2nd century BC by astronomer Hipparchus of Rhodes, and it is speculated that he may have been consulted in the machine's construction.

The knowledge of this technology was lost at some point in antiquity. Similar technological works later appeared in the medieval Byzantine and Islamic worlds, but works with similar complexity did not appear again until the development of mechanical astronomical clocks in Europe in the fourteenth century. All known fragments of the Antikythera mechanism are now kept at the National Archaeological Museum in Athens, along with a number of artistic reconstructions and replicas of the mechanism to demonstrate how it may have looked and worked.

🔗 Internet culture

In Internet culture, the 1% rule is a rule of thumb pertaining to participation in an internet community, stating that only 1% of the users of a website add content, while the other 99% of the participants only lurk. Variants include the 1–9–90 rule (sometimes 90–9–1 principle or the 89:10:1 ratio), which states that in a collaborative website such as a wiki, 90% of the participants of a community only consume content, 9% of the participants change or update content, and 1% of the participants add content.

Similar rules are known in information science, such as the 80/20 rule known as the Pareto principle, that 20 percent of a group will produce 80 percent of the activity, however the activity may be defined.

🔗 Computing

A dial box is a computer peripheral for direct 3D manipulation e.g. to interactively input the rotation and torsion angles of a model displayed on a computer screen. Dial boxes were common input tools in the first years of interactive 3D graphics and they were available for Silicon Graphics (SGI) or Sun Microsystems and sold with their workstations. Currently they have been replaced by standard computer mouse interaction techniques.

Standard dial box has 8 dials mounted on a plate. The plate is set upright with the help of a stand and usually located next to the computer screen for convenient access. The connection to a computer is made via the serial port (RS-232).

One of the fields of application for dial boxes was molecular graphics.

🔗 Climate change 🔗 Environment 🔗 Geology

Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term is named for Serbian geophysicist and astronomer Milutin Milanković. In the 1920s, he hypothesized that variations in eccentricity, axial tilt, and precession resulted in cyclical variation in the solar radiation reaching the Earth, and that this orbital forcing strongly influenced climatic patterns on Earth.

Similar astronomical hypotheses had been advanced in the 19th century by Joseph Adhemar, James Croll and others, but verification was difficult because there was no reliably dated evidence, and because it was unclear which periods were important.

Now, materials on Earth that have been unchanged for millennia (obtained via ice, rock, and deep ocean cores) are being studied to indicate the history of Earth's climate. Though they are consistent with the Milankovitch hypothesis, there are still several observations that the hypothesis does not explain.