'Stick filaments'
on solar UV 171Å and 304Å images

Filaments sometimes start as "sticks," on ultraviolet images.

(Originally, that is a week ago, I called sticks "stalks" but have since found that stalks are already defined as the long thin tips to coronal streamers, reaching far out into space. Probably better thought of as "spikes on the helmet streamers". "Sticks" are in the low corona.)

Red/cyan goggles as needed to see these amnaglyphs in 3D Use red/cyan anaglyph goggles to see in 3D

 

At 11 o'clock, a stick sits in a coronal magnetic cavity (171Å, stereoscopic anaglyph)

Stalk filament in a solar coronal magnetic hamock

There are two sticks, one at each end of a filament, as is shown here

 

Another stick, in 171Å stereoscopic image, sits above right (NW) of the 5th May 2007 solar flare.

Stalk filament near the 20070505 solar flare

The above stick at 304Å, showing how it changes over 12 hours

Gif movie showing a stalk filament changing in 12 hours

The stick is stable over hours, unlike a smoke stack which only lasts for around 15 minutes or even less.

This stick leads to fine filaments, rather like telephone wires, stretching to the south. The "wires" are really only visible on the later image, when the stick has rotated closer to the disc edge. (20070505-125045 UTC).

There are other filaments and prominences in this picture which do not have sticks.

Many of the large sticks on 304Å images are just filaments seen on end. Filaments do not show well on 171Å images, while sticks do.

Small sticks on 304Å images are spicules. Spicules are usually recognised near the edge of the sun, especially in coronal holes, but they can be seen on the disc in 304Å 3D images:

Spicules and filament at the center of the solar disc, seen stereoscopically

 

Image credit: NASA/JPL-Caltech/NRL/GSFC.
Anaglyphs and gif movie by John Wattie.
Words by John Wattie.

A group of many spicules are in a rough row from 4 to 5 o'clock.

A short but high filament lies from 10 to 11 o'clock and a bigger filament shows at 9 o'clock.

Many other un-named details are seen stereoscopically.

The much enhanced stereoscopic perceived depth at the middle of the solar disc showed up on stereoscopic pairs taken 2nd of August, 2007. At this stage the STEREO space craft were too far apart for a realistic depiction of solar roundness and the sun looked as if it was elongated towards the observer. Only the middle could be fused stereoscopically and the rest of the disc had too much disparity for even an expert 3D audience. Excessive disparity has been used to enhance depth details of coins stereoscopically, but here it exaggerates solar details to advantage.

 

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