Strong evidence for coronal heating theory by nanoflares
Clear evidence now suggests that the heating mechanism depends on regular but intermittent explosive bursts of heat, rather than on continuous gradual heating.
NASA's EUNIS sounding rocket examined light from the sun in the area shown by the white line (imposed over an image of the sun from NASA's Solar Dynamics Observatory) then separated the light into various wavelengths (as shown in the lined images — spectra — on the right and left) to identify the temperature of material observed on the sun. The spectra provided evidence to explain why the sun's atmosphere is so much hotter than its surface.
Credit: NASA/EUNIS/SDO
Image credits: buffonescience7.wikispaces & http://folk.uio.no/gardini/sun.html
The Sun’s surface is blisteringly hot at 10,340° F (5,730° C) — but its atmosphere is another 300 times hotter. This has led to an enduring mystery for those who study the Sun: What heats the atmosphere to such extreme temperatures? Normally, when you move away from a hot source, the environment gets cooler, but some mechanism is clearly at work in the solar atmosphere, the corona, to bring the temperatures up so high.
Clear evidence now suggests that the heating mechanism depends on regular but intermittent explosive bursts of heat, rather than on continuous gradual heating.
Read more at Astronomy Magazine.
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