Sun’s Magnetic Pole Flip Shown In NASA Visualization
This visualization shows the position of the sun's magnetic fields from January 1997 to December 2013. The field lines swarm with activity: The magenta lines show where the sun's overall field is negative and the green lines show where it is positive. A region with more electrons is negative, the region with less is labeled positive. Additional gray lines represent areas of local magnetic variation.
The entire sun's magnetic polarity, flips approximately every 11 years -- though sometimes it takes quite a bit longer -- and defines what's known as the solar cycle. The visualization shows how in 1997, the sun shows the positive polarity on the top, and the negative polarity on the bottom. Over the next 12 years, each set of lines is seen to creep toward the opposite pole eventually showing a complete flip. By the end of the movie, each set of lines are working their way back to show a positive polarity on the top to complete the full 22 year magnetic solar cycle.
At the height of each magnetic flip, the sun goes through periods of more solar activity, during which there are more sunspots, and more eruptive events such as solar flares and coronal mass ejections, or CMEs. The point in time with the most sunspots is called solar maximum.
Credit: NASA/GSFC/PFSS
This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?11429
Sun's Magnetic Field Almost Completely Reversed, Marking Midpoint of Solar Cycle 24 [VIDEOS] : Space : Nature World News
The Sun's magnetic field is poised to completely flip, an event that happens every 11 years. Solar physicists began anticipating the reversal of polarity this summer, reporting in August that the reversal would be complete in the coming months. The polarity of the star's northern hemisphere already appears to have reversed and the southern hemisphere should be complete soon, scientists report.
Sun's magnetic field flip means intergalactic storms are on the way | Mail Online
The sun’s magnetic field is on the verge of flipping upside down as its north and south poles swap sides. The phenomenon, which happens once every 11 years, will send ‘ripple effects’ throughout the solar system. It could cause intergalactic weather fronts such as geomagnetic storms, which can interfere with satellites and cause radio blackouts.
Stellar magnetic field - Wikipedia, the free encyclopedia
A stellar magnetic field is a magnetic field generated by the motion of conductive plasma inside a star. This motion is created through convection, which is a form of energy transport involving the physical movement of material. A localized magnetic field exerts a force on the plasma, effectively increasing the pressure without a comparable gain in density. As a result, the magnetized region rises relative to the remainder of the plasma, until it reaches the star's photosphere. This creates starspots on the surface, and the related phenomenon of coronal loops.
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The magnetic field of a rotating body of conductive gas or liquid develops self-amplifying electric currents, and thus a self-generated magnetic field, due to a combination of differential rotation (different angular velocity of different parts of body), Coriolis forces and induction. The distribution of currents can be quite complicated, with numerous open and closed loops, and thus the magnetic field of these currents in their immediate vicinity is also quite twisted. At large distances, however, the magnetic fields of currents flowing in opposite directions cancel out and only a net dipole field survives, slowly diminishing with distance. Because the major currents flow in the direction of conductive mass motion (equatorial currents), the major component of the generated magnetic field is the dipole field of the equatorial current loop, thus producing magnetic poles near the geographic poles of a rotating body.
The magnetic fields of all celestial bodies are often aligned with the direction of rotation, with notable exceptions such as certain pulsars. Another feature of this dynamo model is that the currents are AC rather than DC. Their direction, and thus the direction of the magnetic field they generate, alternates more or less periodically, changing amplitude and reversing direction, although still more or less aligned with the axis of rotation.
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