Wednesday -- I took a parasol out to the telescope for shade and camped under it at the eyepiece for almost an hour. Yesterday's autumn clarity is gone, replaced by the usual summer haze, and the sun is a little lower since I got home later. Nevertheless, more of the prominence on the trailing limb is visible. It has become a kind of middle eastern confection with ornate columns holding up domes of glowing hydrogen. I counted seven points of contact with the chromosphere, seperated from one another by elaborate and graceful arches. The "portals" beneath the arches are mostly dark but some are crossed by a cobweb of fainter, intermittantly visible stria (think of the center of the Ring Nebula at high magnification). With the telescope in motion, detail within the "ceilings" leaps out -- so many bright knots and streaks that I have only managed to suggest them in the original of this sketch. For the first time, the sheer amount of visible detail exceeds my ability to get it all down, despite two pages of annotated field drawings. [14 Aug 1996, 18:40 EDT]



This is the best example I have yet seen of a loop prominence. But not a complete, clean classical one even so. These features are on the south, leading edge of the sun.

Another first for today: vague markings are visible against the face of the sun. They are practically invisible except when the telescope is in motion and their passage through the field of view attracts the eye. I have not attempted to depict these. The most conspicuous area of this broad and subtle patchwork seems to be associated with a sunspot group in the northern hemisphere about halfway between the trailing limb and the meridian. The leading group consists of three or four tiny spots sharing a poorly developed penumbra; the trailing spot appears to be just a naked umbra -- these impressions are from the H-a filtered-view, not from a full aperture white light inspection. Closer to the center of the disk from this presumably bipolar group, surface structure is definitely (but hardly "clearly") visible. Also, just inside the leading limb (on a radius connecting the center of the disk and the loop prominences) is a patch of vague structure. The third, and subtlest, is at the same longitude and at a similar latitude but in the northern hemisphere. [1996 August 14 18:30 EDT]

What's so tough about hydrogen-alpha sungazing? The fine details within prominences demand the same skills used for intermittantly seen planetary detail -- the scale and contrast is similar to the smaller features of Jupiter's belts, for example. "Surface" markings seem to call for the same skills one brings to the deep sky -- especially the rocking and sweeping of the telescope to let the eye catch slight contrast differences. And the profusion of detail is like lunar observing -- you have to pick a detail and stick to it without being distracted by neighboring bits.

Next Observations: Friday
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Take me home!