Hellmuth Walter: Only catch fire? Fuel is supposed to explode, scattering droplets which dissolve human flesh, and contamina…
Sergey Korolev: No, actually, it’s not supposed to.
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I was wrong – there is a kind of analogy to palladium – using open cell foam.
There’s another problem with hydrogen – hydrogen embrittlement. I only watched half of Fran’s video so I don’t know if she mentioned it.
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to be fair…
…
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They originally used expanded aluminum sheet.
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On that note, it looks like the Walter HWK 109-509 had a specific impulse of about 180 seconds with flesh-melting fuel, the NK-33 297 seconds at sea level with kerosene, the F-1 263 seconds at sea level with kerosene, and the J-2 200 seconds at sea level with hydrogen fuel, but 421 seconds in vacuum.
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FTA:
The greater a clock’s accuracy, the more energy it dissipates and the more entropy it produces in the course of ticking.
“A clock is a flow meter for entropy,” said Milburn.
They found that an ideal clock — one that ticks with perfect periodicity — would burn an infinite amount of energy and produce infinite entropy, which isn’t possible. Thus, the accuracy of clocks is fundamentally limited.
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… and that’s why I’m late for work.
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Archaeology and historical linguistics:
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You can translate amino acid sequences into music, but the results haven’t been aesthetically satisfying.
Until now…
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You know what else is 11 dimensions?
M-Theory.
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My brain still does not accept the existence of a fourth.
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Don’t you think it’s TIME you did?
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After the brain processed the information, the clique and cavity vanished.
I assume this is talking about the signals and not the connections themselves?
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(no paywall)
The mission was born of necessity.
Thirty years ago, the concept of planetary formation was much more orderly than it is today. A star formed in the center of a rotating disc of protoplanetary material. Gradually, the material condensed and collected into eight planets in simple orbits (as well as Pluto).
However, when Hal Levison, a planetary scientist, and fellow theorists tried to simulate the formation of the solar system, they repeatedly ran into a problem: It was virtually impossible to build Uranus and Neptune in their present orbits. To account for those worlds, known as the ice giants, Dr. Levison, now the principal investigator of the Lucy mission, and three other researchers developed the Nice model of solar system evolution (named for the city in France).
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Is this what we need with COVID and global warming?
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Jeffrey von Bezos says yes.
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