#photosphere

The images above were drawn on an especially active day for the Sun, near the peak of the 11-year-long solar activity cycle. There was an enormous amount of complexity in the sunspots and many of the sunspots were superlatively large.

There are two main types of solar telescopes: White light, and Hydrogen Alpha.

Left: my 6" Dobsonian with a 5" Baader AstroSolar white light filter. Right: my Coronado PST, a 40mm Hydrogen-alpha solar refractor.

In white light, we see structures on the Sun's 'surface,' the Photosphere. We see sunspots and faculae.

In H-alpha light, we see structures in the Sun's 'atmosphere,' the Chromosphere. We see sunspots, plages, filaments, and prominences.

Sunspots: Regions of intense magnetic field activity that interrupt the flow of heat from inside the star. The photosphere in the sunspot cools down from 5800K to around 3500K, which is still enough to glow, but gets darkened to black by the filter.

Faculae: Where does the energy blocked by sunpots end up? The faculae. These are web-like bright patches which are mostly visible at the limb (edge) of the Sun. Thanks to faculae, when there are sunspots, the Sun is actually slightly more luminous than when there are none. Faculae are hard to spot in the more common yellow-tinted white light filter. They're reasonably easy in a blue-tinted one, but I am privileged to own a Baader AstroSolar filter which gives a true color pure white image.

Plages: More regions of magnetic field activity that result in a brightening of the chromosphere.

Prominence: These are eruptions of material where the magnetic fields pull hydrogen into huge loops that are often larger than the Earth. When they're seen against space, they look light; when they're seen against the sun, they look like dark scratches and we call them filaments.

Occasionally you'll see astrophotos of the Sun's chromosphere that are colored orange or even yellow. The actual color of the chromosphere is bright pink, and you can sometimes see it during Total Solar Eclipses. But the brightest single wavelength of the chromosphere, the one targeted by solar filters, is the Hydrogen Alpha line, which is a deep deep red. I've tried to replicate that in the digital colorizations of my pencil sketches.

My log book for the chromosphere drawings is a midtone grey sketchbook. I use black sharpie for the space-black, white colored pencils for the plages and prominences, and black colored pencils for the filaments and sunspots. The paper also has a kinda hairy texture to it, which is nice because it looks a little like the supergranulation on the chromosphere.

You can see a few filaproms--filaments that are visible on the limb both against space (light) and against the sun (dark).

Here's one from 2021-Jan-6. No sunspots this day, just filaments and some very nice prominences.

Here's one from December 30, 2020.

The Coronado PST Solar telescope was a christmas gift from my mother that year. She got it at a massive discount (These things usually go for like $700, I think she paid $200) because it came from the collection of a local observatory host who'd died.

2021-January-9. Decent proms but not much going on otherwise.

The prominence on the upper right was very notable. It even had these sort of puffs of 'smoke' trailing behind it so to speak. It also changed hour to hour. Features on the Sun can move very rapidly indeed, and it's rare to be able to see changes on a celestial body in almost real time.