Hello friends!
As an amateur #astronomer , I have had focused for the last couple of months in #solar imaging. The sun follows a cyclical pattern of activity every 11 years approximately, called a solar cycle. This cycle alternates between lulls in activity (the "solar minimum") and lots of it (the "solar maximum"). We are just starting a new solar cycle, so activity is just starting to ramp up. In other words, now is a good time to start observing our 🌞 star! (WITH THE PROPER FILTERING EQUIPMENT OF COURSE 😎 ).
At the amateur level, there are two main types of solar observation techniques, which depend on the filtering of the light coming from the sun: continuum white light ("white light" to keep it simple) and hydrogen alpha. White light observing consists on using a special filter to block almost all the light coming from the sun to make it safe for viewing, just like the material used for eclipse glasses. That filtering technique lets you see the sun's #photosphere, which is the visible outer layer of the sun. In there, you'll see what are commonly called #sunspots (usually appearing in what astronomers call "Active Regions").
White light observing is the more accessible technique, given that within the cost range of astronomy equipment, it is relatively inexpensive. It's also very exciting to watch almost daily, since the photosphere changes in appearance all the time! Only "boring time" would be during the solar minimum, when there's not a lot going on *using WL filtering*.
The other #solar #observing technique commonly available for amateur #astronomers is hydrogen alpha filtering, which involves using a more specialized equipment to filter out ALL wavelengths of light coming from the sun except a very narrow sliver of wavelength called the hydrogen alpha line (see Balmer lines if you want to know more about that). In the visible spectrum, the hydrogen alpha line (Ha for short) is within the deep red part of the spectrum. This filtering allows us to observe some jaw-dropping activity on the sun at almost all times!
When we observe the sun under Ha filtering, we are able to see the sun's #chromosphere and its #prominences. The chromosphere is a gaseous layer, mainly hydrogen, which lays above the #photosphere. The high temperatures at that layer causes the hydrogen to glow red at that wavelength, hence the Ha name. Also, you could be able to see a #prominence, which is an eruption-like event of solar material thrown out into space!
The drawback of hydrogen alpha observing for us amateurs is that the cost of manufacturing the filtering equipment is somewhat high, due to the exacting tolerances and safety precautions needed to handle all that energy concentrated into a telescope. Watching the sun through a telescope without the proper filtering can result in instant and permanent blindness !
Within a #sunspot, the #penumbra is the darker area that surrounds the #umbra, even darker still. Darker in this case means cooler, but not cooler as in cold, but as in "ultra horribly hot" instead of "super mega ultra horribly hot". Pores are like smaller sunspots without a penumbra, light bridges sometimes split the umbra into several sections, and granules are convective cells of plasma on the sun's surface. The look small, but given that the sun's diameter is ~109 times Earth's, all of these sunspots are much larger than Earth!
Ok, that was it! Thanks for reading if you actually made it this far! Bye!