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🔗 Geology

The Chesapeake Bay impact crater was formed by a bolide that impacted the eastern shore of North America about 35.5 ± 0.3 million years ago, in the late Eocene epoch. It is one of the best-preserved "wet-target" impact craters in the world.

Continued slumping of sediments over the rubble of the crater has helped shape the Chesapeake Bay.

🔗 Aviation 🔗 Aviation/aircraft

The Airbus Beluga XL (Airbus A330-743L) is a large transport aircraft based on the Airbus A330 airliner. The aircraft entered service with Airbus Transport on 9 January 2020 to replace the Airbus Beluga in the movement of oversized aircraft components, for example wings. The Beluga XL made its first flight on 19 July 2018, and received its type certification on 13 November 2019.

It made its first operational flight on January 9, 2020, and by January 20, had entered full-time service.

🔗 Ancient Near East 🔗 Meteorology 🔗 Meteorology/droughts and fire events 🔗 Ancient Egypt

The 4.2-kiloyear BP aridification event was one of the most severe climatic events of the Holocene epoch. It defines the beginning of the current Meghalayan age in the Holocene epoch. Starting in about 2200 BC, it probably lasted the entire 22nd century BC. It has been hypothesised to have caused the collapse of the Old Kingdom in Egypt as well as the Akkadian Empire in Mesopotamia, and the Liangzhu culture in the lower Yangtze River area. The drought may also have initiated the collapse of the Indus Valley Civilisation, with some of its population moving southeastward to follow the movement of their desired habitat, as well as the migration of Indo-European-speaking people into India.

Some scientists disagree with this conclusion and point out that the event was neither a global drought nor did it happen in a clear timeline.

🔗 Time

The Symmetry454 calendar (Sym454) is a proposal for calendar reform created by Irv Bromberg of the University of Toronto, Canada. It is a perennial solar calendar that conserves the traditional month pattern and 7-day week, has symmetrical equal quarters in 82% of the years in its 293-year cycle, and starts every month on Monday.

🔗 Military history 🔗 Military history/Early Modern warfare 🔗 Military history/American Revolutionary War 🔗 Military history/Maritime warfare 🔗 Ships 🔗 Connecticut

Turtle (also called American Turtle) was the world's first submersible vessel with a documented record of use in combat. It was built in 1775 by American David Bushnell as a means of attaching explosive charges to ships in a harbor, for use against Royal Navy vessels occupying North American harbors during the American Revolutionary War. Connecticut Governor Jonathan Trumbull recommended the invention to George Washington, who provided funds and support for the development and testing of the machine.

Several attempts were made using Turtle to affix explosives to the undersides of British warships in New York Harbor in 1776. All failed, and her transport ship was sunk later that year by the British with the submarine aboard. Bushnell claimed eventually to have recovered the machine, but its final fate is unknown. Modern replicas of Turtle have been constructed and are on display in the Connecticut River Museum, the U.S. Navy's Submarine Force Library and Museum, the Royal Navy Submarine Museum, and the Oceanographic Museum (Monaco).

🔗 Korea 🔗 Business 🔗 Japan 🔗 Japan/Business and economy

Simultaneous recruiting of new graduates or periodic recruiting of new graduates (新卒一括採用, Shinsotsu-ikkatsu-saiyō) is the custom that companies hire new graduates all at once and employ them. This custom was unique to Japan and South Korea. A 2010 age discrimination law enforced in South Korea bans employers from discriminating against job-seekers who have not recently graduated from high school or university. Japan is now the only country practising this custom; however, in 2018, the Japan Business Federation (Keidanren) announced that its 1,600 member companies, which represent a large portion of Japan's big business companies, would no longer be required to follow the custom from 2020 onwards.

🔗 Economics 🔗 Business 🔗 Sociology 🔗 Occupations

This is a category of jobs that have been rendered obsolete due to advances in technology and/or social conditions.

🔗 Crime 🔗 Mining

Sand theft or unauthorised or illegal sand mining leads to a widely unknown global example of natural and non-renewable resource depletion problem comparable in extent to global water scarcity. Beach theft is illegal removal of large quantities of sand from a beach leading to full or partial disappearance of the beach.

🔗 Physics 🔗 Physics/Fluid Dynamics

Granular convection, or granular segregation, is a phenomenon where granular material subjected to shaking or vibration will exhibit circulation patterns similar to types of fluid convection. It is sometimes described as the Brazil nut effect when the largest particles end up on the surface of a granular material containing a mixture of variously sized objects; this derives from the example of a typical container of mixed nuts, where the largest will be Brazil nuts. The phenomenon is also known as the muesli effect since it is seen in packets of breakfast cereal containing particles of different sizes but similar density, such as muesli mix.

Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells similar to fluid motion. The convection of granular flows is becoming a well-understood phenomenon.

🔗 Computing 🔗 Computing/Computer hardware

The transputer is a series of pioneering microprocessors from the 1980s, featuring integrated memory and serial communication links, intended for parallel computing. They were designed and produced by Inmos, a semiconductor company based in Bristol, United Kingdom.

For some time in the late 1980s, many considered the transputer to be the next great design for the future of computing. While Inmos and the transputer did not achieve this expectation, the transputer architecture was highly influential in provoking new ideas in computer architecture, several of which have re-emerged in different forms in modern systems.