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June 20, 2021 Archives
Sunday, June 20, 2021
CONTINUITY: Ada Augusta Lovelace's Bernoulli Numbers—The First Computer Program
This video uses Fourmilab's edition of the Countess of Lovelace's “Sketch of the Analytical Engine” from our Analytical Engine Web resources. Not discussed is the arm-waving in implied by the statement “Here follows a repetition of Operations thirteen to twenty-three.” in the Bernoulli number computation chart. How Babbage intended looping to work in the Analytical Engine was ill-defined, and the Bernoulli number computation makes glaringly evident the need for an index register or indirect addressing to access columns in the Store. This is discussed in my document “Is the Emulator Authentic?”.
Posted at
13:13
THE HAPPENING WORLD: International Space Station: Second EVA to Upgrade Solar Arrays
Update: New solar panel successfully deployed. (2021-06-21 00:00 UTC)
View of the fully deployed IROSA. pic.twitter.com/13YYpEOcCu
— Pete 🚀 🛰 (@Space_Pete) June 20, 2021
Posted at
12:03
CONTEXT: Near-Zero Thermal Coefficient of Expansion
A record of thermal stability: Scandium-Tungsten-Aluminium Oxide exhibits zero expansion between 4K and 1400K:https://t.co/tTTXPfd1eb pic.twitter.com/zvhG7h57Ya
— ToughSF (@ToughSf) June 19, 2021
Posted at
11:42