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Neil deGrasse Tyson

  • Muhammadhar citeretfor 2 år siden
    Quarks are quirky beasts. Unlike protons, each with an electric charge of +1, and electrons, with a charge of –1, quarks have fractional charges that come in thirds. And you’ll never catch a quark all by itself; it will always be clutching other quarks nearby. In fact, the force that keeps two (or more) of them together actually grows stronger the more you separate them—as if they were attached by some sort of subnuclear rubber band. Separate the quarks enough, the rubber band snaps and the stored energy summons E = mc2 to create a new quark at each end, leaving you back where you started
  • Muhammadhar citeretfor 2 år siden
    Zwicky studied the movement of individual galaxies within a titanic cluster of them, located far beyond the local stars of the Milky Way that trace out the constellation Coma Berenices (the “hair of Berenice,” an Egyptian queen in antiquity). The Coma cluster, as we call it, is an isolated and richly populated ensemble of galaxies about 300 million light-years from Earth.
  • Muhammadhar citeretfor 2 år siden
    These are ordinary dangers. From the department of exotic happenings, intergalactic space is regularly pierced by super-duper high-energy, fast-moving, charged, subatomic particles. We call them cosmic rays. The highest-energy particles among them have a hundred million times the energy that can be generated in the world’s largest particle accelerators. Their
  • Muhammadhar citeretfor 2 år siden
    When we examine the Coma cluster, as Zwicky did during the 1930s, we find that its member galaxies are all moving more rapidly than the escape velocity for the cluster. The cluster should swiftly fly apart, leaving barely a trace of its beehive existence after just a few hundred million years had passed. But the cluster is more than ten billion years old, which is nearly as old as the universe itself. And so was born what remains the longest-standing unsolved mystery in astrophysics
  • Nalin chawlahar citeretfor 6 måneder siden
    The universe is under no obligation to make sense to you.

    —NDT
  • Ximena García Rodríguezhar citeretfor 2 år siden
    Dominance was their goal; increase of knowledge was incidental.
  • Ximena García Rodríguezhar citeretfor 2 år siden
    America was showcasing its stealth bombers, virtually invisible to enemy radar and unseeable in the absence of moonlight. Not a cosmic accident. The attack was timed to coincide with the new Moon, the only phase not visible at any time of the day or night.
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