A Solar Diversion
I'm finally beginning to feel "halfway" decent lately which is a tremendous change in my health since September of last year so I'm now trying to catch up on little (and big) projects that need to be accomplished around the house. I've done some raking outside on a rare sunny day... I've replaced a leaky bathroom faucet... I've replaced our locksets and deadbolts... I installed all the window screens around the house... I've rebuilt and restored an older computer to use for astronomy... I installed a new focuser on a fairly large telescope... I've tuned up and adjusted my largest telescope mount... then, yesterday morning, when I saw that we had a sunny day with some decent visibility, I had to pull out my newest telescope to view the sun!
Decent visibility is a rarity these days and it significantly impacts viewing the sky, day or night, with a telescope. This is why NASA prefers to launch their telescopes into space to view from there. Honestly, our skies in Vermont are not nearly as "clear" as they used to be 20-something years ago when I moved here. Even on the rare day when the sun is shining, you can see a light haze when looking at the surrounding mountains. The sky is rarely a deep crystal clear blue. This light haze makes viewing with a telescope difficult even if the sky is cloudless. Visibility is just as much a limiting factor as clouds.
So, as I was getting ready to start my day yesterday morning, it was looking fairly decent outside so I didn't want to pass up a rare decent day for solar observing.
After taking my morning dose of medications, I started collecting the astronomy gear I would need for a short viewing session. A "short viewing session" really means about two or three hours by the time you set everything up, view in various configurations, shoot photos in between each configuration, and then tear down and put everything back in its place. This short viewing session would take me to lunchtime.
As always, I started wide... getting the whole sun in the view. I was clearly able to see two sunspots. They would slowly shimmer in and out of focus... a sign that the visibility and viewing isn't the best. The atmosphere was definitely affecting my viewing but I had two sunspots visible so I knew I wanted to capture a few photos.
In all, throughout my session yesterday morning, I captured about 440 photos. Most of these photos were not crisp or even quite out of focus... mostly due to the visibility issue but also due to difficulty focusing because of the shimmering of the view going in and out of focus. Focusing is difficult even on something as large as the sun! I did manage to find a handful of crisp photos from this session to show here. Looking at these numbers, it appears as though my keeper rate for solar astrophotography is around 1 to 100.
This first photo shows the whole sun. We can clearly see the two sunspots... the dark spots at around the 10 o'clock position and also inward toward the center of the sun. These sunspots are areas of lower temperature due to magnetic field flux.
Near the outermost sunspot, we can see some areas of lighter detail. These lighter details are called faculae. These are areas that are slightly hotter. The average temperature of the surface of the sun is around 27 million degrees. (And I'm not even a fan of temperatures above a measly 80 degrees! Temperatures consistently above 80 degrees severely impacts my health.)
You can also just barely begin to see some granulation in the surface of the sun. The granulation is the bubbling of the surface. It is easier to see through the telescope than it is to image it but we can just barely see some of it here, below.
Below, is a closer view of the area of the sun that has two sunspots. It is a little easier to see the faculae on the far side of the sunspot farthest from us here in this photo. That fairly coarse grain on the surface of the sun is a bit of the granulation. Another thing we can clearly see here is the penumbra of the sunspots. This is the lighter shaded area surrounding the sunspot. My seeing/visibility wasn't so great so all we see in this penumbra is a lighter shade. Typically, the penumbra shows squiggly lines moving outward from the sunspot. Oh, and we can also see a smaller dot in the 8 o'clock position under the rightmost sunspot... this is a newer sunspot developing.
Something I forgot to mention... this photo, above, is a stack of four images. After I stacked the images so I can eek out a little more detail while suppressing some noise and dust on my sensor (unfortunately, stacking four images did not get all of the sensor dust... I really need to clean my sensor), I noticed that I captured a satellite passing over Earth! You can see it toward the upper right corner of the image, above, the little dot moves across the field of view in each of the four stacked images.
And, this last shot moves in slightly closer to take a look a bit more closely at that far sunspot (which I think is in AR 2741... AR 2740 is in the foreground, above).
It is always nice to take a break from the everyday mundane things that need to be done around the house and do something we enjoy instead. When the weather provides for some astronomy, I like to jump in and take advantage of the clear skies!
Decent visibility is a rarity these days and it significantly impacts viewing the sky, day or night, with a telescope. This is why NASA prefers to launch their telescopes into space to view from there. Honestly, our skies in Vermont are not nearly as "clear" as they used to be 20-something years ago when I moved here. Even on the rare day when the sun is shining, you can see a light haze when looking at the surrounding mountains. The sky is rarely a deep crystal clear blue. This light haze makes viewing with a telescope difficult even if the sky is cloudless. Visibility is just as much a limiting factor as clouds.
So, as I was getting ready to start my day yesterday morning, it was looking fairly decent outside so I didn't want to pass up a rare decent day for solar observing.
After taking my morning dose of medications, I started collecting the astronomy gear I would need for a short viewing session. A "short viewing session" really means about two or three hours by the time you set everything up, view in various configurations, shoot photos in between each configuration, and then tear down and put everything back in its place. This short viewing session would take me to lunchtime.
As always, I started wide... getting the whole sun in the view. I was clearly able to see two sunspots. They would slowly shimmer in and out of focus... a sign that the visibility and viewing isn't the best. The atmosphere was definitely affecting my viewing but I had two sunspots visible so I knew I wanted to capture a few photos.
In all, throughout my session yesterday morning, I captured about 440 photos. Most of these photos were not crisp or even quite out of focus... mostly due to the visibility issue but also due to difficulty focusing because of the shimmering of the view going in and out of focus. Focusing is difficult even on something as large as the sun! I did manage to find a handful of crisp photos from this session to show here. Looking at these numbers, it appears as though my keeper rate for solar astrophotography is around 1 to 100.
This first photo shows the whole sun. We can clearly see the two sunspots... the dark spots at around the 10 o'clock position and also inward toward the center of the sun. These sunspots are areas of lower temperature due to magnetic field flux.
Near the outermost sunspot, we can see some areas of lighter detail. These lighter details are called faculae. These are areas that are slightly hotter. The average temperature of the surface of the sun is around 27 million degrees. (And I'm not even a fan of temperatures above a measly 80 degrees! Temperatures consistently above 80 degrees severely impacts my health.)
You can also just barely begin to see some granulation in the surface of the sun. The granulation is the bubbling of the surface. It is easier to see through the telescope than it is to image it but we can just barely see some of it here, below.
Below, is a closer view of the area of the sun that has two sunspots. It is a little easier to see the faculae on the far side of the sunspot farthest from us here in this photo. That fairly coarse grain on the surface of the sun is a bit of the granulation. Another thing we can clearly see here is the penumbra of the sunspots. This is the lighter shaded area surrounding the sunspot. My seeing/visibility wasn't so great so all we see in this penumbra is a lighter shade. Typically, the penumbra shows squiggly lines moving outward from the sunspot. Oh, and we can also see a smaller dot in the 8 o'clock position under the rightmost sunspot... this is a newer sunspot developing.
Something I forgot to mention... this photo, above, is a stack of four images. After I stacked the images so I can eek out a little more detail while suppressing some noise and dust on my sensor (unfortunately, stacking four images did not get all of the sensor dust... I really need to clean my sensor), I noticed that I captured a satellite passing over Earth! You can see it toward the upper right corner of the image, above, the little dot moves across the field of view in each of the four stacked images.
And, this last shot moves in slightly closer to take a look a bit more closely at that far sunspot (which I think is in AR 2741... AR 2740 is in the foreground, above).
It is always nice to take a break from the everyday mundane things that need to be done around the house and do something we enjoy instead. When the weather provides for some astronomy, I like to jump in and take advantage of the clear skies!
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