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October 15, 2021 Archives
Friday, October 15, 2021
THE HAPPENING WORLD: Shenzhou-13 Crew Launch to Chinese Tiangong Space Station
Shenzhou-13 launch is scheduled for 16:23 UTC on 2021-10-15. The launch is to carry a crew of three to the Tiangong space station for a planned six-month stay.
Posted at
14:11
TRACKING WITH CLOSEUPS: Prelude FLNG—600,000 Tonne Floating Liquefied Natural Gas Plant
Here is more about Prelude FLNG. It is 488 metres long, 74 metres high, and rises 105 metres above the water line. Unpowered, it is towed into position by oceangoing tugboats, then tethered to the sea floor by chains and connected to well head equipment by flexible pipes. It is designed to be able to ride out a category 5 cyclone, and has the ability to “weathervane” into the wind.
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12:47
CONTEXT: The Agoric Approach to Computing
Agoric computing is a concept of structuring computation and business systems around the model of a free market, supplanting traditional systems which often resemble top-down, centrally planned economies. It encompasses smart contracts, which are central to the emerging field of decentralised finance (DeFi), which is not entirely 100% scams and pyramid schemes, despite how it may appear. In this 42 minute long conversation, the CEO and Chief Scientist of Agoric Systems Operating Company trace the history of smart contracts back to the pioneering work at the American Information Exchange (AMIX) in the 1980s (backed by Autodesk from 1988 through 1992), describe how smart contracts are integrated with blockchain technology, and explain why they have chosen JavaScript as the language on which to build their technology.
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12:18
THE HAPPENING WORLD: Lucy—Visiting Eight Asteroids with One Spacecraft
NASA's Lucy mission is scheduled to launch on Saturday, 2021-10-16 at 09:34 UTC. Its planned twelve-year mission will use multiple Earth gravity assists to fling it on a path through both the leading and trailing Trojan regions of Jupiter, where it will encounter seven asteroids, including some believed to date from early in the formation of the solar system. Lucy will also fly by a small main belt asteroid on its outbound trajectory. Here is a live Webcast of the launch.
Posted at
11:57
CONTINUITY: Before GPS—The Navy Navigation Satellite System
This 1967 U.S. Navy training film describes the Transit satellite navigation system, which went into service in 1964, providing global coverage with position fixes every several hours at the equator and more frequently at higher latitudes. Its original mission was providing position information to Polaris ballistic missile submarines, and was later adopted by a wide variety of surface ships. The architecture was very different from GPS, and relied upon Doppler measurement of transmissions from a constellation of five satellites in low polar orbit. Each satellite transmitted an ephemeris of its position, updated daily from a computer centre on the ground and a network of tracking stations, from which shipboard computers could calculate position based upon the observed Doppler shift. Only one satellite was needed to provide 2D (latitude and longitude) accurate to originally 400 metres but eventually improved to around 200 metres as the system was refined. The Transit system remained in service until 1996, when it was retired in favour of the Global Positioning System (GPS), which had become fully operational (continuous global coverage) the preceding year, but since the 1980s had provided better and more frequent 3D position fixes than Transit.
Posted at
11:19