Our nearest star
The Sun, our nearest star, is one of the most interesting objects in the sky to observe as its activity rises and falls.
A small telescope (please read our observing guide first, as looking at the Sun can be dangerous) will show you the sunspots as they appear and disappear, depending on the sunspot cycle. At times there are many sunspots while at other times there may be none.
A telescope will also show you apparent “surface” of the Sun with its granulation giving it a mottled look. The disk of the Sun can also been seen to not be as bright all over, the edge being very slightly darker than the middle. Near the edge of the solar disk bright patches of light called “faculae” are sometimes seen.
There’s a lot to look out for.
If you feel you want to do a bit more, you can also try counting the sunspots on a daily basis using one of our monthly counting forms (this is in MS Excel) and sending your results in to the Solar Section by email at the end of each month. This is one of the ways we monitor solar activity in the SPA. Another project is to try drawing sunspots and other solar features.
More advanced is the viewing of solar “prominences”. These are seen at the edge of the solar disk using a Hydrogen-alpha filter. These filters (often combined now with a purpose-made small portable telescope) will show features on the solar disk called “filaments” and “plages”. Occasionally bright solar flares may be seen too if you are looking at just the right moment.
Taking images of the Sun a daily basis is a highly rewarding experience provided you stick to the safe methods explained in our observing guide.
The Sun can also be imaged in Hydrogen-alpha and in Calcium light (CaK) using purposely manufactured filters and scopes. This is more difficult to do but is worth the effort.
Solar eclipses are rare but can be seen if you are in the right geographical location at the right time. Check the SPA home page or the SPA’s Twitter feed for news of any forthcoming eclipses. Reports of solar eclipses and any unusual solar activity seen by our members will appear in our Solar News section.
Remember that the Sun is the only celestial object that can cause injury to the eyes, or even blindness. Never make your own solar filters from household items. Never look at the Sun with the naked eye even when it is low in the sky or covered by mist or fog. Never take unnecessary risks while solar observing.
If you wish to join the Solar Section, you are welcome to do so but you must be a member of the SPA. If you would like to send images of the Sun, or you just have some questions, please email me or write to me at my address (available from the latest issue of “Popular Astronomy”).
John Chapman-Smith