What Are the Linear Dark Features on the Sun?

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SUMMARY

The linear dark features observed on the Sun are scientifically identified as coronal holes, which represent gaps in the solar corona. These features often exhibit a thin jagged light line along their center, resembling dark spikes that obscure solar flares and spicules. Additionally, some of these features may correspond to filaments or spicules, which are small plasma jets. The discussion highlights the importance of viewing these phenomena in different wavelengths, such as hydrogen alpha (Ha), to gain a clearer understanding of their nature.

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TL;DR
What are the long linear dark features on the Sun, with a thin light jagged centreline and dark spikes above?
I’ve been watching
https://www.youtube.com/watch?v=l3QQQu7QLoM
What is the scientific name of the enigmatic long linear dark features? I’ve marked five of them in the first image, from time 7:55 in the video.

Each linear dark feature usually (but not always) has a thin jagged light line along the centreline. At the limb of the Sun, each jagged centreline appears as a dark spike that protrudes well above the surroundings and is so dark that it obscures flares and spicules behind it. The second image from 0:33 shows three such dark spikes, two on the left and one on the right, which are always aligned with the thin centreline of a dark feature.

If you think of the dark spikes above the thin jagged centreline as cloud tops, then there is often lightning that plays along these cloud tops. These are flashes of light along this very thin central line. It can be faint and almost continuous, localised, can zoom from one end of the line to the other like a speeding car on the highway, or go bang all at once. These flashes are not high above the photosphere like flares, but seem contained within the cloud tops.

Anyway, what is the scientific name for these?
 

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Andrew Mason said:
I think you may be referring to solar flares. Seen from above rather than the side flares can look like dark lines as in these Wikipedia photos: https://en.m.wikipedia.org/wiki/Solar_flare

AM

I don't see any obvious flares in in any of the boxed regions. and the flares would be bright not dark

mollwollfumble said:
What is the scientific name of the enigmatic long linear dark features? I’ve marked five of them in the first image, from time 7:55 in the video

in the first pic ...

1593939683014.png


These long dark areas are gaps in the corona called coronal holes. Some of them may also be some face on filaments there as well
tho that X-ray wavelength doesn't show filaments so well compared to Ha (hydrogen Alpha) images.

Now the second image shows a different feature...

1593939880956.png


The left box outlines a very small filament/prominence ( also not well seen at these wavelengths)
These could also be spicules - small plasma jets as they look similar to small prominences when viewed side on

The right box may also be one, but much less defined
cheers
Dave
 
mollwollfumble said:
I’ve been watching

What a great video...a complete solar cycle in an hour. Thanks. (I don't know the answer...)
 
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