Starship Asterisk*

Sunspots on an Active Sun

Explanation: Why is our Sun so active now? No one is sure. An increase in surface activity was expected because our Sun is approaching solar maximum in 2025. However, last month our Sun sprouted more sunspots than in any month during the entire previous 11-year solar cycle -- and even dating back to 2002. The featured picture is a composite of images taken every day from January to June by NASA's Solar Dynamic Observatory. Showing a high abundance of sunspots, large individual spots can be tracked across the Sun's disk, left to right, over about two weeks. As a solar cycle continues, sunspots typically appear closer to the equator. Sunspots are just one way that our Sun displays surface activity -- another is flares and coronal mass ejections (CMEs) that expel particles out into the Solar System. Since these particles can affect astronauts and electronics, tracking surface disturbances is of more than aesthetic value. Conversely, solar activity can have very high aesthetic value -- in the Earth's atmosphere when they trigger aurora.

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It's certainly active, I was able to photograph the aurora from Southern England. Let's hope it doesn't get too active...

If you stare at it long enough and defocus, you might see a 3D teapot.

LOL. Imagine that much activity in a single day.

The statement about the composition of the image leaves me confused. If it were really a composite of ALL daily images of the Sun over 6 months, wouldn't we be seeing thick lines instead of the blobs that we see here? The two week reference seems to indicate that only images taken about two weeks apart were used to make up the composite. No?

johnnydeep wrote: ↑Tue Jul 11, 2023 8:58 pm The statement about the composition of the image leaves me confused. If it were really a composite of ALL daily images of the Sun over 6 months, wouldn't we be seeing thick lines instead of the blobs that we see here? The two week reference seems to indicate that only images taken about two weeks apart were used to make up the composite. No?

No, this makes sense for daily images. The spacing for individual spots is right for a day between them (the Sun rotates once every 27 days, and you'll notice that long lasting sunspots produce about 14 images across the face of the Sun). Most sunspots only last a few days, with a few lasting a few solar rotations (but changing in appearance during the 14 days they are invisible to us).

At first it looke like the sun had freckles! but to look closer; it was
repeats of thf same sunspot being repeated!
https://apod.nasa.gov/apod/ap141022.html
I think I liked the you tube movie better! Kitty; did you catch the fish? or did the fish get you?

Chris Peterson wrote: ↑Tue Jul 11, 2023 9:31 pm

johnnydeep wrote: ↑Tue Jul 11, 2023 8:58 pm The statement about the composition of the image leaves me confused. If it were really a composite of ALL daily images of the Sun over 6 months, wouldn't we be seeing thick lines instead of the blobs that we see here? The two week reference seems to indicate that only images taken about two weeks apart were used to make up the composite. No?

No, this makes sense for daily images. The spacing for individual spots is right for a day between them (the Sun rotates once every 27 days, and you'll notice that long lasting sunspots produce about 14 images across the face of the Sun). Most sunspots only last a few days, with a few lasting a few solar rotations (but changing in appearance during the 14 days they are invisible to us).

Thanks. So are you saying that you could get the same composite using an image only every 24 hours for a month? Where does the use of using a 6 month time period come in? I suppose that would catch more spots since as you said, many are not long lasting? But then I would think the resulting composite would show a lot more spots!

johnnydeep wrote: ↑Wed Jul 12, 2023 6:49 pm

Chris Peterson wrote: ↑Tue Jul 11, 2023 9:31 pm

johnnydeep wrote: ↑Tue Jul 11, 2023 8:58 pm The statement about the composition of the image leaves me confused. If it were really a composite of ALL daily images of the Sun over 6 months, wouldn't we be seeing thick lines instead of the blobs that we see here? The two week reference seems to indicate that only images taken about two weeks apart were used to make up the composite. No?

No, this makes sense for daily images. The spacing for individual spots is right for a day between them (the Sun rotates once every 27 days, and you'll notice that long lasting sunspots produce about 14 images across the face of the Sun). Most sunspots only last a few days, with a few lasting a few solar rotations (but changing in appearance during the 14 days they are invisible to us).

Thanks. So are you saying that you could get the same composite using an image only every 24 hours for a month? Where does the use of using a 6 month time period come in? I suppose that would catch more spots since as you said, many are not long lasting? But then I would think the resulting composite would show a lot more spots!

Well, you're going to image about six times more sunspots over six months than you would in one month, right? This composite DOES show a lot more spots!

Chris Peterson wrote: ↑Wed Jul 12, 2023 7:36 pm

johnnydeep wrote: ↑Wed Jul 12, 2023 6:49 pm

Chris Peterson wrote: ↑Tue Jul 11, 2023 9:31 pm

No, this makes sense for daily images. The spacing for individual spots is right for a day between them (the Sun rotates once every 27 days, and you'll notice that long lasting sunspots produce about 14 images across the face of the Sun). Most sunspots only last a few days, with a few lasting a few solar rotations (but changing in appearance during the 14 days they are invisible to us).

Thanks. So are you saying that you could get the same composite using an image only every 24 hours for a month? Where does the use of using a 6 month time period come in? I suppose that would catch more spots since as you said, many are not long lasting? But then I would think the resulting composite would show a lot more spots!

Well, you're going to image about six times more sunspots over six months than you would in one month, right? This composite DOES show a lot more spots!

Ok. I was thinking it would look a lot more messy than this image does if really done over 6 months, but I guess not. I'm curious what an actual month long daily composite would show. There's probably no easy way to determine from this 6 month composite which sunspots belong to which month.

johnnydeep wrote: ↑Wed Jul 12, 2023 8:05 pm

Chris Peterson wrote: ↑Wed Jul 12, 2023 7:36 pm

johnnydeep wrote: ↑Wed Jul 12, 2023 6:49 pm

Thanks. So are you saying that you could get the same composite using an image only every 24 hours for a month? Where does the use of using a 6 month time period come in? I suppose that would catch more spots since as you said, many are not long lasting? But then I would think the resulting composite would show a lot more spots!

Well, you're going to image about six times more sunspots over six months than you would in one month, right? This composite DOES show a lot more spots!

Ok. I was thinking it would look a lot more messy than this image does if really done over 6 months, but I guess not. I'm curious what an actual month long daily composite would show. There's probably no easy way to determine from this 6 month composite which sunspots belong to which month.

No, the timing information is lost in a composite like this. You could, of course, download the imagery (which is public) and make your own composite, with just a month. It would look similar... just about six times less messy.

Chris Peterson wrote: ↑Wed Jul 12, 2023 8:23 pm

johnnydeep wrote: ↑Wed Jul 12, 2023 8:05 pm

Chris Peterson wrote: ↑Wed Jul 12, 2023 7:36 pm

Well, you're going to image about six times more sunspots over six months than you would in one month, right? This composite DOES show a lot more spots!

Ok. I was thinking it would look a lot more messy than this image does if really done over 6 months, but I guess not. I'm curious what an actual month long daily composite would show. There's probably no easy way to determine from this 6 month composite which sunspots belong to which month.

No, the timing information is lost in a composite like this. You could, of course, download the imagery (which is public) and make your own composite, with just a month. It would look similar... just about six times less messy.

✓