Have a deep view into what people are curious about.

🔗 Physics

The green flash and green ray are meteorological optical phenomena that sometimes occur transiently around the moment of sunset or sunrise. When the conditions are right, a distinct green spot is briefly visible above the upper rim of the Sun's disk; the green appearance usually lasts for no more than two seconds. Rarely, the green flash can resemble a green ray shooting up from the sunset or sunrise point.

Green flashes occur because the earth's atmosphere can cause the light from the Sun to separate out into different colors. Green flashes are a group of similar phenomena that stem from slightly different causes, and therefore, some types of green flashes are more common than others.

🔗 Spaceflight 🔗 China

PAS-22, previously known as AsiaSat 3 and then HGS-1, was a geosynchronous communications satellite, which was salvaged from an unusable geosynchronous transfer orbit by means of the Moon's gravity.

🔗 Volcanoes 🔗 Astronomy 🔗 Solar System 🔗 Solar System/Moon

Lunar lava tubes are lava tubes on the Moon formed during the eruption of basaltic lava flows. When the surface of a lava flow cools, it hardens and the lava can channel beneath the surface in a tube-shaped passage. Once the flow of lava diminishes, the tube may drain, forming a hollow void. Lunar lava tubes are formed on sloped surfaces that range in angle from 0.4° to 6.5°. These tubes may be as wide as 500 metres (1,600 ft) before they become unstable against gravitational collapse. However, stable tubes may still be disrupted by seismic events or meteoroid bombardment.

The existence of a lava tube is sometimes revealed by the presence of a "skylight", a place in which the roof of the tube has collapsed, leaving a circular hole that can be observed by lunar orbiters.

🔗 Apple Inc. 🔗 Computing

The term bozo bit has been used in two contexts. Initially a weak copy protection system in the 1980s Apple classic Mac OS, the term "flipping the bozo bit" was later reused to describe a decision to ignore a person's input. It is a whimsical term, possibly derived from the classic children's comedy character, Bozo the Clown.

🔗 Spaceflight 🔗 Astronomy

J002E3 is the designation given to an object in space discovered on September 3, 2002, by amateur astronomer Bill Yeung. Initially thought to be an asteroid, it has since been tentatively identified as the S-IVB third stage of the Apollo 12 Saturn V rocket (designated S-IVB-507), based on spectrographic evidence consistent with the titanium dioxide in the paint used on the rockets. The stage was intended to be injected into a permanent heliocentric orbit in November 1969, but is now believed instead to have gone into an unstable high Earth orbit which left Earth's proximity in 1971 and again in June 2003, with an approximately 40-year cycle between heliocentric and geocentric orbit.

🔗 Physics 🔗 Systems 🔗 Systems/Chaos theory

In condensed matter physics, Hofstadter's butterfly describes the spectral properties of non-interacting two dimensional electrons in a magnetic field. The fractal, self-similar, nature of the spectrum was discovered in the 1976 Ph.D. work of Douglas Hofstadter and is one of the early examples of computer graphics. The name reflects the visual resemblance of the figure on the right to a swarm of butterflies flying to infinity.

The Hofstadter butterfly plays an important role in the theory of the integer quantum Hall effect, and D.J. Thouless has been awarded the Nobel prize in physics in 2016 for the discovery that the wings of the butterfly are characterized by Chern integers, the quantized Hall conductances discovered in 1980 by Klaus von Klitzing for which he has been awarded the Nobel prize in 1985. The colors in the diagram reflect the different Chern numbers.

🔗 Religion 🔗 Central Asia 🔗 Archaeology 🔗 Visual arts 🔗 Buddhism 🔗 World Heritage Sites 🔗 Religion/Interfaith 🔗 Public Art 🔗 Afghanistan 🔗 Sculpture 🔗 Hazara

The Buddhas of Bamiyan were two 6th-century monumental statues of Vairocana Buddha and Gautama Buddha carved into the side of a cliff in the Bamyan valley of central Afghanistan, 130 kilometres (81 mi) northwest of Kabul at an elevation of 2,500 metres (8,200 ft). Carbon dating of the structural components of the Buddhas has determined that the smaller 38 m (125 ft) "Eastern Buddha" was built around 570 AD, and the larger 55 m (180 ft) "Western Buddha" was built around 618 AD.

The statues represented a later evolution of the classic blended style of Gandhara art. The statues consisted of the male Salsal ("light shines through the universe") and the (smaller) female Shamama ("Queen Mother"), as they were called by the locals. The main bodies were hewn directly from the sandstone cliffs, but details were modeled in mud mixed with straw, coated with stucco. This coating, practically all of which wore away long ago, was painted to enhance the expressions of the faces, hands, and folds of the robes; the larger one was painted carmine red and the smaller one was painted multiple colors. The lower parts of the statues' arms were constructed from the same mud-straw mix supported on wooden armatures. It is believed that the upper parts of their faces were made from great wooden masks or casts. The rows of holes that can be seen in photographs held wooden pegs that stabilized the outer stucco.

The Buddhas are surrounded by numerous caves and surfaces decorated with paintings. It is thought that the period of florescence was from the 6th to 8th century AD, until the onset of Islamic invasions. These works of art are considered as an artistic synthesis of Buddhist art and Gupta art from India, with influences from the Sasanian Empire and the Byzantine Empire, as well as the country of Tokharistan.

The statues were blown up and destroyed in March 2001 by the Taliban, on orders from leader Mullah Mohammed Omar, after the Taliban government declared that they were idols. International and local opinion strongly condemned the destruction of the Buddhas. Some Taliban sources credited Omar's decision to blow up the Buddha statues to the growing influence of Osama bin Laden.

🔗 Crime 🔗 COVID-19 🔗 Women's History

The Signal for Help (or the Violence at Home Signal for Help) is a single-handed gesture that can be used by an individual to alert others that they feel threatened and need help over a video call, or in-person. It was originally created as a tool to combat the rise in domestic violence cases around the world as a result of the self-isolation measures related to the COVID-19 pandemic.

The signal is performed by holding one hand up with the thumb tucked into the palm, then folding the four other fingers down, symbolically trapping the thumb in the rest of the fingers. It was intentionally designed as a single continuous hand movement, rather than a sign held in one position, that could be made easily visible.

The Signal for Help was first introduced in Canada by the Canadian Women's Foundation on April 14, 2020, and on April 28, 2020 in the United States by the Women's Funding Network (WFN). It received widespread praise from local, national, and international news organizations for helping provide a modern solution to the issue of a rise in domestic violence cases.

Addressing concerns that abusers may become aware of such a widespread online initiative, the Canadian Women's Foundation and other organizations clarified that this signal is not "something that's going to save the day," but rather a tool someone could use to get help.

Instructions for what to do if an individual sees the signal, and how to check-in safely, were also created.

🔗 Technology 🔗 Computing 🔗 Medicine 🔗 Molecular and Cell Biology 🔗 Medicine/Medical genetics

DNA digital data storage is the process of encoding and decoding binary data to and from synthesized strands of DNA.

While DNA as a storage medium has enormous potential because of its high storage density, its practical use is currently severely limited because of its high cost and very slow read and write times.

In June 2019, scientists reported that all 16 GB of text from Wikipedia's English-language version have been encoded into synthetic DNA.

🔗 Crime 🔗 Law 🔗 Law Enforcement 🔗 Automobiles 🔗 Ireland

"Prawo Jazdy" was a supposed Polish national who was listed by the Garda Síochána in a police criminal database as having committed more than 50 traffic violations in Ireland. A 2007 memorandum stated that an investigation revealed prawo jazdy [ˈpra.vɔ ˈjaz.dɨ] to be Polish for 'driving licence', with the error arising due to officers mistaking the phrase, printed on Polish driving licenses, to be a personal name while issuing traffic tickets.