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February 20, 2021 Archives
Saturday, February 20, 2021
TRACKING WITH CLOSEUPS: Gabriel's Horn—Finite Volume but Infinite Surface Area
Here is more on Gabriel's Horn. Interestingly, as long as the curve rotated is continuously differentiable, there is no surface of revolution which has finite surface area and infinite volume.
Posted at
14:55
CONTEXT: Bill Gates: Showing One’s Work and Getting the Right Answer Are “Racist”
After spending decades polluting the world with incompetently-designed, shoddily-implemented, and unreliable software, Bill Gates declares getting the right answer is “racist”. https://t.co/VXywZXpnA3 From 1996, my “Top Ten”: https://t.co/NSxIItaxSD
— John Walker (@Fourmilab) February 20, 2021
Posted at
13:52
THE HAPPENING WORLD: Antares Cargo Launch to the International Space Station
There’s a 75% chance of favorable weather at Wallops for launch of the Antares rocket at 12:36pm EST (1736 GMT), with the main concern being a chance of low cloud ceiling, the range weather officer says.
— Spaceflight Now (@SpaceflightNow) February 20, 2021
Teams are also tracking strong upper level winds.https://t.co/RgAiRHpx8b
Posted at
13:44
CONTINUITY: Corgi Movie Vision—Kid Vid from the 1970s
Sadly, there do not seem to be any movies of corgis! This thing ought to have been given away by the manufacturers of D-cell batteries.
Posted at
12:59
THE HAPPENING WORLD: Rocket Sky-Crane Delivers Nuclear-Powered Aircraft Carrier to Alien Planet
Perseverance: How to Land on Mars: https://t.co/50MJhf9Oxd by @NASA, @NASAJPL, Mars 2020 pic.twitter.com/Wq4H5rwyos
— Astronomy Picture Of The Day (@apod) February 20, 2021
“Aircraft carrier?"—yes, indeed.
Posted at
11:57
TRACKING WITH CLOSEUPS: Owl Bet You Don't See Me
The amazing camouflage of the great grey owl. Over the course of its evolution, any gene that happened to make the owl a little less visible had a greater chance of being passed on. The gradual accumulation of such genes led to the near-perfect camouflage we see today. pic.twitter.com/a1xFEpp30k
— Steve Stewart-Williams (@SteveStuWill) February 19, 2021
Posted at
11:54