Motion Inside the Sun Untangled

[Waspie_Dwarf]

NASA's SDO Mission Untangles Motion Inside the Sun

Using an instrument on NASA's Solar Dynamics Observatory, called the Helioseismic and Magnetic Imager, or HMI, scientists have overturned previous notions of how the sun's writhing insides move from equator to pole and back again, a key part of understanding how the dynamo works. Modeling this system also lies at the heart of improving predictions of the intensity of the next solar cycle.

Using SDO, scientists see a performance of explosions and fountains on the solar surface. Shots of solar material leap into the air. Dark blemishes called sunspots grow, combine and disappear as they travel across the sun's face. Bright loops of charged particles – captured by magnetic fields dancing around the sun – hover in the atmosphere. This dynamic display is all powered by a complex, ever-changing magnetic current inside the sun known as the dynamo. This magnetic system flips approximately every 11 years, with magnetic north and magnetic south switching poles. This process is an integral part of the sun's progression toward a pinnacle of solar activity, known as solar maximum..

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[Waspie_Dwarf]

NASA SDO - Mission Untangles Motion Inside the Sun

Helioseismic observations from my HMI (Helioseismic and Magnetic Imager) instrument revealed that meridional circulation in the solar interior has a double-cell structure with an equatorward flow located in the middle of the convection zone about 60,000 miles beneath the visible surface of the Sun.

Meridional circulation, which transports solar materials between low and high latitudes inside the Sun, is a fundamental property of the Sun, but was poorly known. It is widely believed that the circulation plays an important role in redistributing solar angular momentum and transporting magnetic flux, setting up 11-year solar activity cycles. Previously it was thought that the circulation had a single-cell structure with a poleward flow near the surface and an equatorward flow located near the bottom of the convection zone.

Through analyzing the unprecedented high-quality helioseismic data obtained fromHMI by using a helioseismic analysis technique called time-distance helioseismology, the solar physicists found that the solar meridional currents have at least two circulation cells in each hemisphere, with an equatorward flow located between about 40,000 and 80,000 miles below the surface. That is, the equatorward flow is roughly in the middle of the convection zone. This result provides a new insight into the dynamics of the solar interior hidden from direct observations, and requires a reexamination of the theories of solar magnetic cycles.

Credit: NASA SDO / Stanford HMI

Source: NASA/SDO - Facebook

[cacoseraph]

Neat!

I wonder if this will shed some light (doh! I am the king of low hanging fruit!) on the coronal heating problem? (Short summary of CHP: the corona is a million degrees, the surface of the sun is around 6,000... no one knows how this happens or even how it CAN happen)

http://en.wikipedia.org/wiki/Corona#Coronal_heating_problem

[Waspie_Dwarf]

I wonder if this will shed some light on the coronal heating problem?

I suspect the answer to that is more likely to come from NASA's recently launched IRIS mission. IRIS stands for Interface Region Imaging Spectrograph and it is designed to look specifically at the region between the photosphere and the corona.

There are quite a few topics on this mission, so if you are interested, search for NASA IRIS and have a read (pre-launch topics are mostly in the Space Exploration and Spaceflight forum, mission results will be posted in this forum).