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Stargazing Is it a true explanation of an aberration of starlight?

  1. Feb 24, 2017 #1
    In 1727, astronomer J. Bradley discovered the phenomenon of stellar aberration. All stars throughout the year on the celestial sphere pass ellipses with an semimajor axis observed from the Earth at an angle of 20.5. Aberration is caused by the movement of the Earth in its orbit around the sun at a speed of 29.8 km / sec. To watch a star from moving Earth you need to tilt а telescope tube forward motion because as long as the light passes a tube. eyepiece with the Earth will move forward.
    Last edited: Feb 24, 2017
  2. jcsd
  3. Feb 24, 2017 #2


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    a what ???

    where did you quote this text from ?
  4. Feb 24, 2017 #3

    Oh, sorry. It's a misprint.

  5. Feb 24, 2017 #4

    Ken G

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    The English in that explanation is not very clear, but the basic idea is there-- as the Earth moves in its orbit, it changes the direction from which starlight appears to arrive. So to find a star in Winter that you saw in Summer, you have to point the telescope slightly differently. It's the reverse effect of the reason why you have to aim in front of a moving target in order to hit it.
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