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User: ydrozd

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  1. Re:It's not an error on Vostochny Launch Building Built To the Wrong Size · · Score: 2

    If you mean "Mir" (which is not the first, BTW, the first was Almaz/Salut circa 1971), it was built by Soviet Union, not Russia. In fact, the most technologically advanced systems, such as nav/docking systems ("Kurs") and "Kvant" controls were developed in Ukraine (Kiev Radiozavod and Kharkiv Elektropribor correspondingly), and are now lost to Russians (esp. given current war with Ukraine). Russia has been leaking science and engineering brains at ever increasing rates; so the failures of their space exploration programs are not surprising.

  2. Re:This is absurd on How an Astronaut Falling Into a Black Hole Would Die Part 2 · · Score: 1

    That is absolutely not true for supermassive black holes, such as the one in the center of our galaxy. For these, the even horizon is far enough from the singularity so that the tidal forces there are not very large.

  3. Re:Conduct an experiment on How an Astronaut Falling Into a Black Hole Would Die Part 2 · · Score: 1

    Hm.. Let's do some math here: LHC *total* beam energy is 362 MJ. Assume that with 100% efficiency ALL the beam energy is used to create micro black hole. It will be pretty small, with a weight of M=J/c^2 = 3.61 * 10^8/ (3 * 10^8)^2 = 4*10^-9 kg. It will not have much pull on the objects around it, so it'd need quite a bit of time to wander around to gobble up additional mass. Fortunately for us, in time t = 5120 * pi *G^2 / ( h * c^4) * M^3 = 3.4 * 10^-27 seconds the black hole will evaporate in a burst of Hawking radiation. Even if you "crank up" LHC to product a 1 kg black hole (you would need 250 million "current" LHCs to do it), the resulting black hole will live for about 8 * 10 ^ -17 seconds (that's 0.00008 picoseconds), before evaporating in a burst equivalent to a large thermonuclear explosion. So, I wouldn't bet on black hole experiments in the near future :-)