When dynamologists disagree…

Posted: August 13, 2010 by tallbloke in Astrophysics, solar system dynamics

Also, fresh from the BBC:

New research suggests that the longer-than-expected period of weak activity may have been linked to changes in the way a hot soup of charged particles called plasma circulated in the Sun.

The study, conducted by Dr Mausumi Dikpati of the National Center for Atmospheric Research in Colorado and her US colleagues, is published in the journal Geophysical Research Letters.

The new research suggests that one reason for the prolonged period of weak activity could be changes in the Sun’s “conveyor belt”.

Graphic of Sun's conveyor belt (Source: Nasa)
The Sun’s conveyor transports plasma across its surface to the pole, where it sinks before rising at the equator

Similar to the Earth’s ocean currents, the Sun’s conveyor transports plasma across its surface to the pole. Here, the plasma sinks into the heart of the Sun before rising again at the equator.

During the 23rd cycle, these currents of fire extended all the way to the poles, while in earlier cycles they only extended about two thirds of the way.

Dr Roger Ulrich of the University of California, Los Angeles, a co-author of the study, said the findings highlighted the importance of our monitoring of the Sun.

The research team used sophisticated computer simulations to show how changes in the conveyor might have affected cycle duration. They found that the increased length of the conveyor and its slower rate of return flow explained the prolonged 23rd cycle.

However, Dr David Hathaway, a solar physicist from Nasa’s Marshall Space Flight Center in Alabama, who was not involved in the latest study, argued that it was the speed and not the extent of the conveyor that was of real importance.

The conveyor has been running at record high-speeds for over five years. Dr Hathaway said: “I believe this could explain the unusually deep solar minimum.”

Read the rest on the BBC website here.

Comments
  1. DirkH says:

    They don’t give any explanation of what could cause this variation in speed; it’s not a cause, it’s a symptom.

  2. Geoff Sharp says:

    DirkH,

    That’s because they have absolutely no clue.

    The blind leading the blind.

  3. tallbloke says:

    The plain fact of the matter is that solar physicists don’t know why the equatorial regions of the sun rotate faster than the polar regions. Some time ago when I asked Leif about this, he pointed me to a big and serious website which laid out the current state of the research and described the problems with the quasi ‘solutions’ they are working on. I read enough to be able to determine that there is no well worked out answer.

    A couple of thoughts, not particularly ‘worked out’ and no claims being made: The surface gravity of the Sun is enormous, and the plasma of the surface layers is highly mobile. The gravity should pull the surface sperical, leaving meridional flows squished out sideways around the equator. From the perspective of an engineer with fluid dynamics experience, it looks to me like a pumping action is taking place. If that is powered by the magnetics of the solar ‘dynamo’, what is powering the dynamo? Homopolar motors induce a considerable back emf across their disk. That energy is lost as heat…

  4. Groping in the dark it is not science. Science or rather knowledge is to seek and, if possible find, a reasonable cause…and if not asking too much, repeatable experimentally at the lab. Back in the XIX century Birkeland gave the correct answer experimentally.
    http://www.holoscience.com/news.php?article=74fgmwne
    Yes, modern physics has become a neo-scholasticism. It is the avoidance of real questions in the pursuit of trivial methodology. It is the memorization of an endless list of names and manipulations in lieu of understanding mechanics. It is the knee-jerk invocation of authority and the explicit squelching of dissent. It is the institutionalized acceptance of censorship and the creation of dogma. Grand Masters like Feynman say “shut up and calculate!”
    http://milesmathis.com/death.html

  5. A naive question: Is the center of the Sun hot or cold?

  6. P.G. Sharrow says:

    Adolfo Giurfa says:
    August 14, 2010 at 9:31 pm

    “A naive question: Is the center of the Sun hot or cold?”

    The center of the sun is under very high compression and density, maybe neutrons only.
    I am not sure temperature is a good measurement of energy. As part of the definition of temperature is atomic vibration frequency.pg

  7. P.G. Sharrow says:
    August 15, 2010 at 5:28 am
    I was just wondering as we don´t feel the heat of our earth´s thermosphere, at around 1500°K perhaps somebody on the surface of the Sun may not feel its own thermosphere. Nobody knows what there is down there. 🙂

  8. tallbloke says:

    I think you mean the mantle or core. The thermosphere is a rareified layer near the top of Earth’s atmosphere, below the exosphere.

  9. DirkH says:

    No, Adolfo means the thermosphere. It’s rarified, but the few atoms that are there are damn hot, that’s why it’s called thermosphere.

    [reply] My mistake, I though Adolfo’s question was about the temperature at the centre of the sun, and by analogy, the temperature at the centre of the Earth.

  10. tallbloke says:

    tallbloke says:
    August 18, 2010 at 12:46 pm

    Leif Svalgaard says:
    August 18, 2010 at 10:02 am

    tallbloke says:
    August 18, 2010 at 9:44 am
    What is at issue is the fact that the Sun is anything but a rigid inelastic object. It’s a big hot wobbly ball of plasma and molten stuff, which has a highly irregular orbit only a couple of times its own diameter. This sets up differential forces across its sphere.

    The last sentence is where you go wrong [apart from the nonsense that Newton’s law don’t apply universally].

    Newton’s laws (plural) apply universally to rigid, inelastic objects, just like he stated, but not to objects like the Sun. It’s easy to prove this with a Newtonian thought experiment, since you like those. Line up three pool balls touching each other. Now shoot a fourth directly at the front of the line. The ball stops dead and the back ball of the chain of four shoots off in the same direction with about the same velocity.

    Now replace the centre ball with an equal mass of bread dough rolled into a ball. What happens is that the energy transmitted from the incoming ball is mostly lost in plasticly deforming the dough, and the back ball hardly moves away from the pack.

    Now replace the centre ball with an elastic rubber ball. What hapens is the rubber ball deforms from the force transmitted by the front ball, and then springs back into shape, pushing the back ball on its way. Some energy is lost in the process as heat and inertial motion, so the back ball still doesn’t move away at the same rate as on the first occasion, and after a delay.

    The Sun has strong surface gravity, so it will pull itself spherical again after the differential forces affecting it have an effect, like the rubber ball being squashed and rebounding. This is why the heliosiesmologists detect signals which coincide with subharmonic periods of planetary motions.

    The Sun is in free fall and does not feel any forces.

    Ah, back to the old mantra.
    Now, I know it is hopeless to try to educate you on this….

    I normally get the calculator hot on winter evenings when there is nothing better to do, but since I need to move forward with the hypothesis sooner than that, I’ll do the math and post it on my blog. Then you can demonstrate mathematically where I got it wrong, or accept that when it comes to knowledge about the fluid mechanics of elastic objects, you are thicker than a navvie’s butty.

    By the way, your astronaut analogy doesn’t work because s/he is in orbit about his/her own centre of mass, unlike the Sun, which is in orbit about the centre of mass of the solar system, which includes the other objects in it.

  11. P.G. Sharrow says:

    Tallboke; your analogy of an elastic sun and not a solid object is a very good description of reality. As far as I know the sun consists of many layers of various density, some solid ( from ridged to plastic) and layers liquid to gas to the surface. The rarefied plasma atmosphere that we see is above that. An elastic ball of many layers, the ridged core rarely in the exact center at any one time. Kind of makes the nuclear event horizon layer dance around doesn’t it? 😉 pg

  12. According to Miles Mathis theory, E/M field has two parts, one the photon “B” emission (repulsion) and gravity (centripetal acceleration). How about the Sun´s E/M ratio?