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Disappearing Sunspots, Minus 50 Gauss/yr

  1. Jul 1, 2010 #1
    A sunspot is a concentrated clump of magnetic energy on the sun's surface that typically varies from 1800 to 3000 Gauss. The earth's magnetic field strength is in comparison 0.3 Gauss.

    Recently Solar physicists have found the magnetic field strength of newly produced sunspots is declining linearly year by year by 50 gauss per year. Why that is happening is not known.

    The magnetic ropes that create sunspots are believed to be created deep within the sun at the tachocline zone which is the boundary between the solar convection zone and the radiative zone.

    Theoretical calculations indicate that the magnetic ropes that are created at the tachocline require a field strength of around 2000 gauss to avoid being broken up during their rise to the solar surface through the turbulent convection zone. The magnetic ropes rise up through the convection zone to the surface of the sun where they form sunspots. If the trend continues the sun will therefore not be capable of producing new sunspots.

    A consequence of the weakening magnetic field of individual sunspots is that the lifetime of recent sunspots is reduced. The typical lifetime of a new sunspot during a normal cycle is around a month. Many of the recently produced weak sunspots break apart in a few days.



  2. jcsd
  3. Jul 1, 2010 #2
  4. Jul 9, 2010 #3
    This is a comparison of solar cycle 24 to solar cycles 21, 22, and 23.

    The newly produced solar cycle 24 sunspots continue to diminish in size, magnetic field strength, and in life time.

    http://www.solen.info/solar/cyclcomp.html [Broken]

    Last edited by a moderator: May 4, 2017
  5. Jul 9, 2010 #4
    As noted in the above comments sunspots are hypothesized be created at the tachocline deep within the sun. The tachocline is the interface to the solar radiative zone and convection zone.


    Also as noted above, the magnetic field strength of the solar cycle 24 sunspots that are being produced at the tachocline are linearly declining. This indicates that the tachocline has been disturbed.

    The following is a possible explanation for what is observed. The sun is move about its barycenter by the large planets. That motion is cyclic. It appears when there is a specific change in direction of the sun's motion about its barycenter the tachocline is disturbed and the sunspot cycle is interrupted.

    This link discusses related solar anomalies. The solar conveyor belt on the surface of the sun has suddenly increased in speed while the conveyor belt deep with the sun has slowed down. The two conveyor belts were previously expected to be linked. I supposed that is also indication that the tachocline deep within the surface of the sun has been interrupted which explains the de-coupling of the surface and deep conveyor belts.


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