Solar MRI Upends Theories of Heat ConvectionCategory: Science & Technology
Posted: July 13, 2012 12:40PM
To call the Sun the heart of the Solar System is far from an understatement as it keeps the system safe from interstellar hazards, warms the inner planets, and is the center of the planets' orbits. Understandably, we want to know how it works as so many things about it can affect us, from sunspots to temperatures. The current theory of how heat from the Sun's core makes it to the surface uses convection currents, but new research from New York University directly challenges this theory.
The Sun, like other stars, is a gigantic ball of fluid gases, including hydrogen and helium. The core is extremely dense and hot to the point of allowing nuclear fusion to occur, and the heat produced by that reaction not only heats the entire star, but keeps it from collapsing in on itself. Modern theories of how heat gets from the core to the surface uses convection currents to cycle the heat through the inner layers. Researchers at NYU however have used high resolution imagery to determine the flow of these inner layers, by carefully measuring the movement of the surface. The result shows the plasma of the outermost layer moving 100 times slower than the theories require.
As this is just one observation, more work will have to be done to confirm the data. If it turns out that the currents really are that slow though, then new theories to explain how the Sun moves heat around internally will have to be developed. It is worth noting though that these currents affect the formation of sunspots and the magnetic field of the Sun, which can affect us on Earth.