…continuedObserving the Sun by Projection
Some sunspots, especially the very small ones called pores, are quiescent. They form, remain basically unchanged, and die out quickly and uneventfully. Large groups, however, can be much more active and may exhibit remarkable changes in a matter of hours. At these times, large-scale (close-up) drawings of the details of the group are desirable, provided the atmosphere is steady enough. After a group reaches its maximum development, its remnants can persist for several weeks.
I try to limit each full-disk drawing to about an hour or less because image rotation becomes apparent after an hour's drift across the sky. With a 2B graphite pencil, I first draw the outline of the umbra (dark central core) and the lighter penumbra of the largest sunspot groups. The smaller spots are then added in. Depending on the level of sunspot activity, I usually forgo drawing the bright patches or faculae around a spot group and just concentrate on the sunspots themselves, especially if the latter are very active or complex. I always check the realism of my sketches with that of the projected image. Finally, the shading of the umbrae and penumbrae are done with SB and EE pencils.
As far as details go, sunspots stand up well under close scrutiny. Noting their fine structure and features can be as exciting as following their evolution and decay across the Sun's disk. There is also a wealth of detail to be drawn in the faculae near the limbs. These sites of intense magnetic fields are as varied in morphology as sunspots, and if time permits the brightest regions of faculae are drawn in after the sunspots have been recorded.
When sunspots are few I record as much detail in the faculae as distinctly visible, along with sometimes highly variable dark filaments that are often sinuous in shape. Solar pores can be so numerous as to be visible across the entire disk, giving the Sun a spectacular appearance. Some of them are quite persistent; others last only several minutes.
When pores are numerous, the solar granulation (convection cells) filling the Sun's blank areas takes on added interest. Granulation, while best recorded on film, is nonetheless incredibly wonderful to observe visually by projection. Seeing conditions can, at rare times, be so steady that I can see individual granules between the fibrils that make up the penumbrae of sunspots!
How you record your data determines how valuable and useful your observations will likely be. I also keep track of the total observing time I've logged. The essential information I note down are the date, beginning and ending times of each drawing to the nearest minute in Universal Time, any unusual activity observed, and the seeing conditions. The times of your drawings are very important because of the rapid, continuous changes occurring on the Sun.
If you want your data to be archived and possibly used by fellow amateurs and professional researchers, you can send them to the Solar Section of the Association of Lunar and Planetary Observers. See ALPO's website for details on the submission process.
Solar observing is challenging. It's best to practice now so that you'll be ready when the next solar maximum arrives. With careful planning and preparation, you too can enjoy many hours of observing pleasure and surprises as each solar cycle rises to its greatest sunspot activity.