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October 21, 2021 Archives
Thursday, October 21, 2021
CONTINUITY: From 1947—Office Automation Before the Computer
Posted at
13:28
CONTINUITY: The Case for Anarchy with Michael Malice and Glenn Beck
Michael Malice's book, The Anarchist Handbook, is a collection of classic works on anarchism by authors including Proudhon, Bakunin, Spooner, Kropotkin, and Rothbard.
Posted at
12:55
CONTEXT: Ducks in a Row
Simulations reveal that ducklings swimming in a single-file formation behind the parent can achieve a wave-riding benefit whereby the wave drag turns positive. Gives a new meaning to "get your ducks in a row" 🦆@JFluidMech #dynamic #equilibrium #swimming https://t.co/HUmZXhhCcV pic.twitter.com/RxNBEXBQjc
— Journal of Fluid Mechanics (@JFluidMech) October 19, 2021
The full paper is “Wave-riding and wave-passing by ducklings in formation swimming”.
Posted at
12:13
CONTINUITY: Ariane 6 Launch Complex
The first flight of Ariane 6 is now expected to be in late 2022. Cost per launch is estimated at €75 million for the two solid booster version (10.35 tonnes to low Earth orbit [LEO]) and €115 million for four solid boosters (21.65 tonnes to LEO). By comparison, the SpaceX Falcon 9 costs around US$ 50 million (~ €43 million) for a launch with recovery of the first stage, with payload of 15.6 tonnes to LEO.
Posted at
11:49