An explanation has been offered for the bewildering fact that the sun ’s standard pressure is much hotter than its surface . The culprits , it is claimed , are small heating plant bursts known as nanoflares .
For those learning about the Dominicus for the first sentence the find that the solar corona is describe as1 - 3 million degrees , while the surface is a mere 6000 ° hundred prompt mental rejection . The corona , a element of the Lord’s Day ’s atmosphere , is heated by radiation from the sun itself – how then can it be not just hotter , but 100 of times hotter ?
The doubtfulness has n’t stoppednagging professional astronomers . " That ’s a bit of a puzzle , " said Jeff Brosius of NASA ’s Goddard Space Flight Center . " thing usually get cooler far out from a blistering author . When you ’re guy a marshmallow you move it nearer to the fire to cook it , not farther off . "
While there have been various theories , none of them have accomplish a bang-up mass of confidence in the scientific community of interests . However , Brosius has now print a paper inThe Astrophysical Journalsupporting the nanoflare theory .
This musical theme hold that small bursts release huge amount of heat into the corposant . Because the corona is so sparse , the heating plant released by these flare has a immense wallop , in a way that would not occur if there were more corpuscle to debase the effects .
While space government agency have sight of satellites devoted to the sunshine , as well as time on huge telescopes , Brosius ' evidence derive from a much cheaper project . The Extreme Ultraviolet Normal Incidence Spectrograph ( EUNIS ) was launch aboard a projectile into the upper atmosphere , attain a peak of 300 kilometer . EUNIS collected just 6 minutes of information before return to Earth , but its spectrogram provided us with across-the-board entropy on the far ultraviolet light emitted by the sun , which the Earth ’s ambience block from open observations .
Scans of a region of the sun known to be magnetically complex ( or “ active ” ) at the time revealed radiation therapy from a eccentric of atomic number 26 that forms at 8.9 million degrees . A patch this hot would cool , spread heat to the surrounds and creating the typical coronal temperatures .
" The fact that we were able to conclude this discharge phone line so understandably from its neighbors is what pull in spectroscopists like me stay awake at night with exhilaration , " say Brosius . " This imperfect line observe over such a tumid fraction of an fighting region really gives us the inviolable evidence yet for the presence of nanoflares . "
While nanoflares may have firmed as the mechanism , we still do not get it on what is causing them , although again several theories exist . Moreover , just last year an substitute suspect , Alfven Waves , gained supportin the same journal .
succeeding missions will seek to investigate the material that makes up the flares .
