Ukazujem Revíziu 2 vytvorenú 05/22/2020 od Ethan See Eng Kiat.

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   Here's some exciting space news.
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   Astronomers have used the Hubble Telescope
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   and a technique pioneered by
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   Albert Einstein to weigh a white
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   dwarf star for the first time.
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   So in 1916, Einstein said that
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   a massive object like a star would
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    actually warp the fabric of spacetime
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    and what that means is that a ray of
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    light going past the star would actually
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    get bent and move in different paths
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    as it was before.
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    In 1936, a Czech engineer named Mandl
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    came knocking on Einstein's door and asked
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    him to do a little calculation.
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    He said what would happen if a star passed in front
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    of another star, and Einstein really
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    didn't want to do it. He was kind of busy but
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    he felt sorry for him and he did the
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    calculation and wrote a paper for Science,
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    very short paper saying if one star passed
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    in front of another star, the distant star
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    would be magnified and distorted by this
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    gravitational lensing effect. And today,
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    gravitational lensing is one of the most
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    powerful tools in astronomy. People use
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    it to measure the size of the universe and
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    to map out dark matter and to find distant
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    galaxies they couldn't find otherwise
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    because they were too dim. What people in
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    space telescope have done is watch as a
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    distant ordinary star passed behind a
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    white dwarf. It was distorted just as
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    Einstein said it would. And by looking at
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    the exact distortion, they were able to
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    calculate how much the white dwarf was
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    distorting spacetime and therefore,
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    what its mass was, which turned out to be
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    two-thirds of the mass of the Sun (more or less), which
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    is what the theory has said. But still,
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    it's good to know. So once more, we have
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    Einstein to thank for yet another discovery
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    even though he died way back in 1955.
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    This is Mike Lemonick for Scientific American.
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    Please take the time to subscribe to our
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    YouTube channel.