Solar physicist David Hathaway of NASA's Marshall Space flight Center in Huntsville, AL and graduate student Lisa Rightmire of the University of Memphis in Tennessee have been monitoring the sun using the Solar and Heliospheric Observatory (SOHO). They observe a massive circulating current of fire (hot plasma) within the sun operating at a faster pace as reported in the March 12th issue of Science.
Diagram of the distribution of the sun's magnetic field over three 11-year solar cycles. Yellow represents magnetic field directed out of the sun. Blue represents magnetic field into the sun. Sunspots themselves produce the "Butterfly" pattern at low latitudes. The sun's meridional flow from the equator to the poles in each hemisphere carries magnetic remains of the sunspots to the poles. This produces the streaks seen at higher latitudes and reverses the magnetic polarity of the sun's poles every 11 years. Image credit: NASA/MSFC/David Hathaway
The current of fire is a conveyor belt-like system called the Meridional Flow which rises to the surface at the sun's equator and spreads out toward the poles where it sinks back into the sun. "Normally it reaches peak speeds of about 20 mph," says Hathaway. "However, in 2004 the speed increased to nearly 30 mph and has remained that fast since."
Video showing the association of magnetic field with sunspots and coronal loops.
The faster pace is a revelation because it occurred during the deepest solar minimum in almost 100 years and indications that the next solar cycle will be a weak one. This contradicts some theories that say a fast pace results in increased sunspot production. But it agrees with others that say a fast pace results in decreased sunspot production.
The faster rate of currents on the sun and the expected weaker solar cycle have affects for those of us here on Earth. One affect is the temperature increase of the Earth could slow down, there would be fewer auroras, and to the extent that we depend on satellites, GPS, and cell phones there should be less disruption in service.
The faster rate of currents on the sun and the expected weaker solar cycle have affects for those of us here on Earth. One affect is the temperature increase of the Earth could slow down, there would be fewer auroras, and to the extent that we depend on satellites, GPS, and cell phones there should be less disruption in service.
For more information about the sun's meridional flow:
"Solar 'Current of Fire' Speeds Up" (Science@NASA article)
"Variations in the Sun's Meridional Flow Over a Solar Cycle" (Science magazine article)
For more information visit http://www.nasa.gov/topics/solarsystem/features/solar_plasma.html
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