Image: Solar Dynamics Observatory spies rare encircling filament

November 9, 2017, NASA
Credit: NASA/GSFC/Solar Dynamics Observatory

NASA's Solar Dynamics Observatory came across an oddity that the spacecraft has rarely observed before: a dark filament encircling an active region (Oct. 29-31, 2017). Solar filaments are clouds of charged particles that float above the sun, tethered to it by magnetic forces.

They are usually elongated and uneven strands. Only a handful of times before have we seen one shaped like a circle.

The black area to the left of the brighter active region is a coronal hole, a magnetically open region of the sun.

While it may have no major scientific value, it is noteworthy because of its rarity. The still was taken in a wavelength of .

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cantdrive85
1 / 5 (4) Nov 09, 2017
The black area to the left of the brighter active region is a coronal hole, a magnetically open region of the sun.
While it may have no major scientific value,

Magnetically open, the author is unknowingly correct that comment has no scientific value.
AlfvenArp
1 / 5 (2) Nov 09, 2017
"While it may have no major scientific value" ... really?! It is an observed process that is taking place that you don't have any viable explanation for and that in and of itself gives it scientific value.
cantdrive85
1 / 5 (2) Nov 09, 2017
Clearly a sockpuppet, most likely da schnied. All magnetic flux is a closed loop, calling something "magnetically open" is meaningless mumbo jumbo.

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