Found The Second Earth

ในห้อง 'Science & Mystery' ตั้งกระทู้โดย supatorn, 16 สิงหาคม 2017.

  1. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
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    145px-LH_95.jpg
    Can the eclipse tell us if Einstein was right about general relativity?

    He probably was, but astronomers will put his 1915 theory to the test with DIY experiments
    By
    Lisa Grossman
    7:00am, August 15, 2017

    story-5_main.jpg
    TRICK OF THE LIGHT Einstein showed that spacetime warps around massive bodies and makes light take different paths, as shown in this stellar smile in which a red galaxy distorts the light from a more distant blue galaxy


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    Almost a century ago, a solar eclipse revealed the geometry of spacetime. Now, physicists and amateur astronomers — armed with do-it-yourself gear — are going to double check that math during the Aug. 21 solar eclipse.
    In his 1915 general theory of relativity, Albert Einstein predicted that the sun’s gravity should distort spacetime in its vicinity. Stars behind the sun would appear in different positions with respect to each other during an eclipse than they would on an ordinary night when the sun is nowhere in sight.

    The theory marked a revolution in physics, transforming the universe from a static, unchanging landscape to a dynamic, malleable playground.

    Just four years later during the May 1919 solar eclipse, British astronomer Arthur Stanley Eddington took photographs that proved Einstein right. “Lights all askew in the heavens,” blared the Nov. 9 New York Times in one of the most famous science newspaper headlines ever. Its subtitle: “Men of science more or less agog over results of eclipse observations.” It vaulted Einstein to international fame — and has launched endless tests of whether or not Einstein was right about general relativity.


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    IN THE DARK Astronomer Arthur Eddington took this image of the eclipsed sun in May 1919, which showed stars in the background in slightly different positions than when the sun wasn’t around. This gravitational lensing proved for the first time that Einstein’s general theory of relativity was correct.
    F.W. Dyson, A. S. Eddington, and C. Davidson
    There’s not really much doubt that he was, to be fair. Relativity has passed every test it has been put to with flying colors (SN: 10/17/15, p. 16).
    “So far, general relativity has been completely, embarrassingly, exactly correct every time one goes out and looks at it,” says astrophysicist Bradley Schaefer of Louisiana State University in Baton Rouge.

    But the Eddington experiment has been repeated only six times, last in 1973. Each test used photographic plates, and the accuracy of the stars’ measured positions was never greater than about 10 percent, Schaefer says. If the stars’ positions actually deviated from Einstein’s predictions but to a lesser degree, those earlier experiments would not have been able to find a measurable difference in the stars’ positions.

    Recent technological advances mean a single person can do 10 times better. And Schaefer intends to be that person.

    “What I’m going to be doing isn’t going to be real frontline research,” Schaefer admits. “This is reproducing one of the all-time great science experiments — and you do it yourself, and you do it much better than it’s ever been done by anyone. Me, I will be testing whether general relativity is right.”

    Advances in digital cameras are the key. As well as being able to snap lots of images quickly, the cameras have CCDs, or charge-coupled devices, that can squeeze thousands of pixels onto a tiny chip. That allows for high-resolution images without needing a large camera.

    CCDs are standard issue in professional telescopes and hobby astrophotography cameras. About two years ago, a CCD camera with 4,096 pixels per side became commercially available. Although it costs almost $10,000, Schaefer didn’t hesitate to snag one.

    “This is what makes it possible to do so much better than Eddington,” Schaefer says. “During the eclipse proper, you take one- or two-second integrations of the sun, bang-bang-bang-bang-bang, and that’s your data. It’s pretty easy.”

    The fact that Eddington’s eclipse was in May but the NYT story ran in November is also significant: Eddington had to wait for the stars to return to the same positions in the sky that they held during the eclipse to verify his results.

    That won’t be a problem for Schaefer: His setup will get the comparison shots overnight. “With a modest amateur telescope and a good CCD camera, one can take all the observations, including calibration, within 24 hours,” Schaefer says.

    Schaefer and a group of other astronomers will start out near Casper, Wyo., but they’re ready to jump in the car and drive anywhere else along the eclipse path if it looks like it might be cloudy. “[We] will be doing this as a mobile exercise,” he says. “My highest concern is actually getting the data.”
    https://www.sciencenews.org/article/2017-solar-eclipse-einstein-general-relativity?tgt=nr
     
  2. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
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    พระสัพพัญญูรู้แจ้งโลก ไทย

    Alexander Fitterling
    Published on Mar 1, 2015

    von Luong Por Tiwa persönlich ของหลวงพ่อทิวา
     
  3. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
    +26,172
    Life in The Universe Documentary | HD 1080p

    photo.jpg
    DocumentaryKingHD
    Published on Jan 23, 2013
     
  4. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
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    The Universe & Beyond the Big Bang Documentary HD 720p

    Real Space

    Published on Apr 23, 2017
     
  5. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
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    Explore The Milky Way Galaxy - Documentary HD

    ADVEXON TV
    Published on Nov 24, 2014
     
  6. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
    +26,172
  7. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
    +26,172
    Universe Documentary 2017 | White Dwarf - Universe's Sleeping Monster | National Geographic

    photo.jpg
    UniverseTV Channel
    Published on Feb 11, 2017

    A white dwarf, also called a degenerate dwarf, is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: its mass is comparable to that of the Sun, while its volume is comparable to that of Earth. A white dwarf's faint luminosity comes from the emission of stored thermal energy; no fusion takes place in a white dwarf wherein mass is converted to energy. The nearest known white dwarf is Sirius B, at 8.6 light years, the smaller component of the Sirius binary star. There are currently thought to be eight white dwarfs among the hundred star systems nearest the Sun. The unusual faintness of white dwarfs was first recognized in 1910. The name white dwarf was coined by Willem Luyten in 1922. The universe has not existed long enough to experience a white dwarf releasing all of its energy as it will take many billions of years
     
  8. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
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    Finding Life Beyond Earth Are we Alone NOVA HD

    AN66SAwDbpkVakdlkZS9cS7kNZZP65SIKjNDIw5XUA=s48-mo-c-c0xffffffff-rj-k-no.jpg
    Star Stuff

    Published on Jan 8, 2015

    Take a spectacular trip to distant realms of our solar system to discover where secret forms of life may lie hidden. Combining the latest telescope images with dazzling animation, this program immerses audiences in the sights and sounds of alien worlds, while top astrobiologists explain how these places are changing how we think about the potential for life in our solar system. We used to think our neighboring planets and moons were fairly boring—mostly cold, dead rocks where life could never take hold. Today, however, the solar system looks wilder than we ever imagined. Powerful telescopes and unmanned space missions have revealed a wide range of dynamic environments—atmospheres thick with organic molecules, active volcanoes, and vast saltwater oceans. This ongoing revolution is forcing scientists to expand their ideas about what kinds of worlds could support life. If we do find primitive life-forms elsewhere in the solar system, it may well be that life is common in the universe—the rule, and not the exception
     
  9. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
    +26,172
    NOVA | Alien Planets Revealed [HD]

    iSpaceAddict
    Published on Jan 28, 2014

    I DO NOT OWN ANY PART OF THIS VIDEO NOR ANY OF THE AUDIO IN IT! ALL OWNERSHIP GOES TO Nova.
     
  10. supatorn

    supatorn ผู้สนับสนุนเว็บพลังจิต ผู้สนับสนุนพิเศษ

    วันที่สมัครสมาชิก:
    14 กรกฎาคม 2010
    โพสต์:
    12,907
    กระทู้เรื่องเด่น:
    161
    ค่าพลัง:
    +26,172
    Finding Life Beyond Earth and Solar System NOVA Full Documentary

    Wise Wanderer
    Published on Aug 28, 2014

    Take a trip to distant realms of our solar system to discover where secret forms of life may lie hidden. Combining the latest telescope images with dazzling animation, this program immerses audiences in the sights and sounds of alien worlds, while top astrobiologist explain how these places are changing how we think about the potential for life in our solar system. We used to think our neighboring planets and moons were fairly boring mostly cold, dead rocks where life could never take hold. Today, however, the solar system looks wilder than we ever imagined. Powerful telescopes and unmanned space missions have revealed a wide range of dynamic environments, atmospheres thick with organic molecules, active volcanoes, and vast saltwater oceans. This ongoing revolution is forcing scientists to expand their ideas about what kinds of worlds could support life. If we do find primitive life-forms elsewhere in the solar system, it may well be that life is common in the universe the rule, and not the exception.
     

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