Let’s Play a Game -> show me the deltas!

[WildWill]

Howdy All Y’all,

I obviously have more to learn about identifying and classifying delta sunspots.  One of the challenges in learning how to identify the delta spots is that there aren’t a lot of good examples. You can find a lot of examples of delta spots, but they are generally not identified specifically on the image. I personally think having a number of images that had the deltas circled - with a line around the edge of the shared Penumbra.  I think that others would also benefit from such an exercise as well. 

So, I’m creating this thread to be a collaborative learning tool. Every time we get a group with deltas, it would be great if a few more experienced members posted images with the deltas clearly identified.  Then the rest of us can try and identify them ourselves, and then come see how we did and post questions about why a particular spot is or isn’t a delta… 

AR13089 is at present classified as beta-gamma-delta. Anyone care to circle the deltas? 
 

Eventually, the material and images in here could be consolidated into a class material for sunspot classification. All Y’all have ya a great day!

WnA 😉

 

[3gMike]

5 hours ago, WildWill said:

Howdy All Y’all,

I obviously have more to learn about identifying and classifying delta sunspots.  One of the challenges in learning how to identify the delta spots is that there aren’t a lot of good examples. You can find a lot of examples of delta spots, but they are generally not identified specifically on the image. I personally think having a number of images that had the deltas circled - with a line around the edge of the shared Penumbra.  I think that others would also benefit from such an exercise as well. 

So, I’m creating this thread to be a collaborative learning tool. Every time we get a group with deltas, it would be great if a few more experienced members posted images with the deltas clearly identified.  Then the rest of us can try and identify them ourselves, and then come see how we did and post questions about why a particular spot is or isn’t a delta… 

AR13089 is at present classified as beta-gamma-delta. Anyone care to circle the deltas? 
 

Eventually, the material and images in here could be consolidated into a class material for sunspot classification. All Y’all have ya a great day!

WnA 😉

 

You need to compare the Magnetogram with the Intensigram - like this

https://gyazo.com/f573b5e2a00453ad042a7d15954f1f41

 

 

 

[Sam Warfel]

3G’s image uploaded here

[WildWill]

23 hours ago, 3gMike said:

You need to compare the Magnetogram with the Intensigram - like this

https://gyazo.com/f573b5e2a00453ad042a7d15954f1f41

 

 

 

That’s all well and good, but, there are a number of spots in the circles you drew. I can see a couple of what I think are delta spots, but I want to know which ones you think are deltas. If you don’t mind, would you go back and just circle the delta spots? 
 

If you are referring to the big bright red one inside your circle. While it is pushed up against that spot, but it appears to have its own penumbra, at least to me.

Question: Can a penumbra have be both polarities, (+) on part of it and (-) on other parts of it? If not, then shouldn’t that dark red spot pushed up against the dark blue one be surrounded in light blue? It’s not. And that seems to me to be my problem with identifying the deltas. I do see two deltas on the south side of the large blue spot you have circled, up tight against it.  I can also see at least one or two other little delta spot outside of your circle. 
 

in addition to the two image types you’ve shown, I’ve also use the magnetogram (non-colorized) as well as the white light images.

A couple of things to keep in mind are that a) both of the images are “false color” and colorized by a computer, which is always going to be imperfect- analog sunspot in a digital world!  The other thing to keep in mind is that some of the images, like the one on the right, are flattened. I’m not sure whether it’s optically or digitally flattened or both, while I don’t think the false color magnetogram is flattened. So, things can be off just a little… the center is right on, but as you move away from the center, the image become more distorted.
 

I appreciate it very much!

 

Cheers!

WnA

😉

 

[Solarflaretracker200]

1 hour ago, WildWill said:

If you don’t mind, would you go back and just circle the delta spots? 

If I’m not wrong, that circled area is the delta 

[3gMike]

14 hours ago, WildWill said:

That’s all well and good, but, there are a number of spots in the circles you drew. I can see a couple of what I think are delta spots, but I want to know which ones you think are deltas. If you don’t mind, would you go back and just circle the delta spots? 
 

If you are referring to the big bright red one inside your circle. While it is pushed up against that spot, but it appears to have its own penumbra, at least to me.

Question: Can a penumbra have be both polarities, (+) on part of it and (-) on other parts of it? If not, then shouldn’t that dark red spot pushed up against the dark blue one be surrounded in light blue? It’s not. And that seems to me to be my problem with identifying the deltas. I do see two deltas on the south side of the large blue spot you have circled, up tight against it.  I can also see at least one or two other little delta spot outside of your circle. 
 

in addition to the two image types you’ve shown, I’ve also use the magnetogram (non-colorized) as well as the white light images.

A couple of things to keep in mind are that a) both of the images are “false color” and colorized by a computer, which is always going to be imperfect- analog sunspot in a digital world!  The other thing to keep in mind is that some of the images, like the one on the right, are flattened. I’m not sure whether it’s optically or digitally flattened or both, while I don’t think the false color magnetogram is flattened. So, things can be off just a little… the center is right on, but as you move away from the center, the image become more distorted.
 

I appreciate it very much!

 

Cheers!

WnA

😉

 

Hi Will,

The way I understand it is that you use the Magnetogram to identify spot polarities, then use the Intensitygram to see where spots of opposite polarity are sitting in the same penumbra. On that basis I would argue that my circles are showing a delta with just two well defined spots of opposite polarity.  If you magnify the image you might pull up some additional smaller spots.

I think it might be possible that you are trying to relate the magnetic fields in the magnetogram with penumbra, and that may be leading to confusion.

The penumbra is simply a warmer region surrounding the (relatively) cooler, dark, sunspot (umbra). The most intense magnetic fields will be associated with the umbra, but I assume that the penumbra may be of a similar polarity. If that is true then there will be mixed polarities in the penumbra of a delta region. Perhaps somebody else is able to comment on that assumption. 

I am basing my definition of Umbra / Penumbra on this information https://www.enchantedlearning.com/subjects/astronomy/sun/sunspots.shtml

[WildWill]

13 hours ago, Solarflaretracker200 said:

If I’m not wrong, that circled area is the delta 

"A delta is a spot. Which spot is the delta?" Or am I wrong?

[MinYoongi]

23 minutes ago, WildWill said:

"A delta is a spot. Which spot is the delta?" Or am I wrong?

Yes, you are wrong. When 2 sunspots share a penumbra, that becomes "a delta spot". its still 2 different individual spots, just within one penumbra, forming the thing we call delta.

[WildWill]

17 minutes ago, MinYoongi said:

Yes, you are wrong. When 2 sunspots share a penumbra, that becomes "a delta spot". its still 2 different individual spots, just within one penumbra, forming the thing we call delta.

I was under the impression that only the spot which is contained within the penumbra of the other spot is the delta spot.

Thank ya fer a settin me straight on that one.

WnA

[Solarflaretracker200]

 

55 minutes ago, MinYoongi said:

Yes, you are wrong. When 2 sunspots share a penumbra, that becomes "a delta spot". its still 2 different individual spots, just within one penumbra, forming the thing we call delta.

Dang I’ve been here for almost a year (November 2nd 2021) and I never knew that till today. 🤣 

 

Edited September 3, 2022 by Solarflaretracker200
I have no idea how I did the wrong year

[WildWill]

3 hours ago, 3gMike said:

Hi Will,

The way I understand it is that you use the Magnetogram to identify spot polarities, then use the Intensitygram to see where spots of opposite polarity are sitting in the same penumbra. On that basis I would argue that my circles are showing a delta with just two well defined spots of opposite polarity.  If you magnify the image you might pull up some additional smaller spots.

I think it might be possible that you are trying to relate the magnetic fields in the magnetogram with penumbra, and that may be leading to confusion.

The penumbra is simply a warmer region surrounding the (relatively) cooler, dark, sunspot (umbra). The most intense magnetic fields will be associated with the umbra, but I assume that the penumbra may be of a similar polarity. If that is true then there will be mixed polarities in the penumbra of a delta region. Perhaps somebody else is able to comment on that assumption. 

I am basing my definition of Umbra / Penumbra on this information https://www.enchantedlearning.com/subjects/astronomy/sun/sunspots.shtml

Howdy 3g!

Ya hit the nail on the head I think.  I have been operating under the belief that a "single penumbra" is associated with a spot and thus, it will have the same polarity as. the spot it "grew from".   
So, a "single penumbra"  will have a single polarity- same as the soot(s) it grew from, not a mixed polarity. 
A delta spot is one of opposite polarity which is contained within the (single) penumbra of a spot of opposite polarity. I've operated under the the belief that the delta spot has no penumbra of its own and exists completely contained within that single penumbra of opposite polarity.

So, what does that mean? look luke?

if you look at the Magnetogram (not the colorized one), then a delta spot should show up as a white spot completely surrounded by black, or a black spot surrounded by white.  Now, when looking at this, keep in mind that a black spot surrounded by white or vice versa, is not necessarily a delta - but if the spot is not surrounded by the opposite polarity, then it's not a delta. Thus the Magnetogram can't tell you if you have a delta, but it can tell you if it is not a delta.  In mathematical terms, it is a necessary but not sufficient condition".  
 

I'll go back to this example.

if we look at the region I have marked off, we can see a big red spot pushed up against that big dark blue spot.  
I have had people tell me this is a delta spot ((the red one).. I've also had people tell me it's not! 
Using my mk 1 mod 0 eyeball, I see that the red spot is not "contained within the penumbra of the blue spot"

Of course, I have made assumption that a single penumbra can only have a single polarity (not counting any delta spots which may be embedded within said penumbra.) 
I've also read that delta spots are often formed by spots of different polarities being pushed together as shown. However, in the process, any penumbra the delta may have had is lost as it is absorbed into the penumbra of the  "dominant spot - the one with the penumbra containing the delta spot.  
 

To iterate, when I look at the image of 3089 above, it doesn't appear to me that the red spot is "completely contained within" the penumbra of the blue spot.  
 

Here, we see another view. To me, it looks like both of the circled spots, while pushed together, they each have their own penumbra... but apparently I am wrong.

So the takeaways here are:

A single penumbra can have both polarities (aside from any delta spots.). 
 

When a pair of spots are "pushed together" as above, the penumbrae can merge and become a single penumbra with both polarities.

Both of these takeaways just don't sit well with me, p gonna have to grok on this a bit...

I had the impression that a single penumbra has a single polarity. This being false makes it very difficult to distinguish a delta for me. 
 

Back to sunspot school fir me!

cheers,

WnA

😉

 

[3gMike]

34 minutes ago, WildWill said:

if you look at the Magnetogram (not the colorized one), then a delta spot should show up as a white spot completely surrounded by black, or a black spot surrounded by white.  Now, when looking at this, keep in mind that a black spot surrounded by white or vice versa, is not necessarily a delta - but if the spot is not surrounded by the opposite polarity, then it's not a delta. Thus the Magnetogram can't tell you if you have a delta, but it can tell you if it is not a delta.  In mathematical terms, it is a necessary but not sufficient condition".  

No - you cannot identify a penumbra from any form of Magnetogram. In the non-colourised version the black indicates negative field areas and white represents positive field areas. The brightness indicates magnetic field strength. In the colourised version the green indicates positive field areas and the blue indicates positive spots. Similarly, yellow represents  negative field areas and red represents negative spots.

https://nso.edu/data/nisp-data/magnetograms/ describes this and gives a good example of the difference between solar min and max.

Penumbra can only be identified on the Intensitygram, and they indicate a temperature zone, around a spot of either polarity, which is warmer than the spot but cooler than the rest of the solar surface.

I hope this helps.

Edited September 3, 2022 by 3gMike
Added link to NISP data

[WildWill]

1 hour ago, 3gMike said:

No - you cannot identify a penumbra from any form of Magnetogram. In the non-colourised version the black indicates negative field areas and white represents positive field areas. The brightness indicates magnetic field strength. In the colourised version the green indicates positive field areas and the blue indicates positive spots. Similarly, yellow represents  negative field areas and red represents negative spots.

https://nso.edu/data/nisp-data/magnetograms/ describes this and gives a good example of the difference between solar min and max.

Penumbra can only be identified on the Intensitygram, and they indicate a temperature zone, around a spot of either polarity, which is warmer than the spot but cooler than the rest of the solar surface.

I hope this helps.

Hey 3g,

Thanks for that! I guru I'm not putting my thoughts into words very well. 
 

Im not saying that you can pick out the penumbra on the Magnetograms.

Ypu also can't determine definitively, if a spot is a delta from the non colorized) Magnetogram . 
 

What I am saying is that

1. we come only determine the polarities within an active region from the Magnetograms.

2. a delta spot is a spot which is surrounded by/contained within a single penumbra of a spot with opposite polarity.

3. The penumbra of a spot has the same polarity as the spot from which it grew.  
 

4, The extent of a penumbrae can only be determined from the "white light" images, like the intensitygram you show.
 

4. Therefore, if a delta is contained within the penumbra of a spot of opposite polarity, then it should appear as a spot (black or white) which is surrounded by the opposite polarity. Again, this assumes that a penumbra and the spot from which it grew have the same polarity ( this is the big question/assumption) in my mind.

I hope this does a better job of expressing my logic.

Again, the big question in my mind, that makes all the difference is: #3 above. 
 

if a spot can grow a penumbra with mixed polarities, then I would agree with the delta you've shown in this thread.  
 

Wrt #4 above. Seeing that black spot embedded in a region which is white on the Magnetogram does not tell you that you have a delta.

however, if you've been looking at the false color Magnetogram and white light images and ya think you have a delta, then you should be able to go to the Magnetogram (non colorized), you should see a spot surrounded by the opposite polarity. If you don't see that, it is not a delta.  Necessary but insufficient on it's own.

To iterate the last point, a spot of one polarity surrounded by the opposite polarity doesn't tell you that you have a delta. But if you go to the Magnetogram to check out what ya think is a delta, and you do not find a spot at that location surrounded by the opposite polarity, you know you do the have a delta.

The Magnetogram (not colorized) can't tell ya you have a delta, but it can sometimes tell you that you don't!

Also, keep in mind that the colorization of the Magnetogram is accomplished with a computer program and can be a little off.

In addition, the white light intensitygram you presented has been "flattened".  So, it's not gonna line up exactly with the Magnetogram. The farther from the center, the more the flattening process distorts the image...

I hope that makes sense to you.

Cheers!

WnA

Also, thank you for the link. I had some questions about the instrumentation and process used o creating the Magnetograms 

Edited September 3, 2022 by WildWill

[Philalethes]

31 minutes ago, WildWill said:

2. a delta spot is a spot which is surrounded by/contained within a single penumbra of a spot with opposite polarity.

This is incorrect, because a delta spot is not at all defined as being surrounded by or contained within a penumbra of a spot with opposite polarity. That's simply not how penumbrae work at all. All the spots in a delta structure will almost invariably have their own penumbrae immediately surrounding them, and whether or not they "share" penumbrae is not really a qualitative matter at all, but solely a quantitative one depending on whether they are sufficiently close for their penumbrae to "merge" into a single one on the i-gram. See e.g. this example from a previous article on this site:

Edited September 3, 2022 by Philalethes Bythos

[3gMike]

16 minutes ago, WildWill said:

Hey 3g,

Thanks for that! I guru I'm not putting my thoughts into words very well. 
 

Im not saying that you can pick out the penumbra on the Magnetograms.

Ypu also can't determine definitively, if a spot is a delta from the non colorized) Magnetogram . 
 

What I am saying is that

1. we come only determine the polarities within an active region from the Magnetograms.

2. a delta spot is a spot which is surrounded by/contained within a single penumbra of a spot with opposite polarity.

3. The penumbra of a spot has the same polarity as the spot from which it grew.  
 

4, The extent of a penumbrae can only be determined from the "white light" images, like the intensitygram you show.
 

4. Therefore, if a delta is contained within the penumbra of a spot of opposite polarity, then it should appear as a spot (black or white) which is surrounded by the opposite polarity. Again, this assumes that a penumbra and the spot from which it grew have the same polarity ( this is the big question/assumption) in my mind.

I hope this does a better job of expressing my logic.

Again, the big question in my mind, that makes all the difference is: #3 above. 
 

if a spot can grow a penumbra with mixed polarities, then I would agree with the delta you've shown in this thread.  
 

Wrt #4 above. Seeing that black spot embedded in a region which is white on the Magnetogram does not tell you that you have a delta.

however, if you've been looking at the false color Magnetogram and white light images and ya think you have a delta, then you should be able to go to the Magnetogram (non colorized), you should see a spot surrounded by the opposite polarity. If you don't see that, it is not a delta.  Necessary but insufficient on it's own.

To iterate the last point, a spot of one polarity surrounded by the opposite polarity doesn't tell you that you have a delta. But if you go to the Magnetogram to check out what ya think is a delta, and you do not find a spot at that location surrounded by the opposite polarity, you know you do the have a delta.

The Magnetogram (not colorized) can't tell ya you have a delta, but it can sometimes tell you that you don't!

Also, keep in mind that the colorization of the Magnetogram is accomplished with a computer program and can be a little off.

In addition, the white light intensitygram you presented has been "flattened".  So, it's not gonna line up exactly with the Magnetogram. The farther from the center, the more the flattening process distorts the image...

I hope that makes sense to you.

Cheers!

WnA

 

Hi Will,

I do understand your difficulty. It took me quite a while to get my head around it !

Try not to think of the delta as relating to any particular spot (or spots) It is a classification for the whole AR. A single penumbra can contain multiple spots of opposite polarity.

The penumbra does not relate directly to the magnetic fields that you see on the magnetograms.

I believe that the reason the colourised magnetogram is sometimes difficult to relate to the Intensitygram is that they have not necessarily been captured at the exact same time.

I have attempted to mark up latest image of AR3089 to illustrate https://gyazo.com/3bd80f409aaad37682ba483d88b7f017

[Newbie]

If sunspot 3098 continues its current rate of growth then a delta or two might be in the offing!

[Newbie]

This has developed a magnetic delta I believe. It is 3098.

.

Edited September 12, 2022 by Newbie

[KW2P]

I'll be watching this thread.

I've been practicing identifying deltas by looking for a spot of a certain polarity surrounded on three sides by the opposite polarity.

[MinYoongi]

15 minutes ago, Newbie said:

This has developed a magnetic delta I believe. It is 3098.

.

Have you compared it to the Intensigrams? There can be different polarities without sharing a penumbra or really having sunspots.

[Newbie]

2 hours ago, MinYoongi said:

Have you compared it to the Intensigrams? There can be different polarities without sharing a penumbra or really having sunspots.

Yeah I have Min in my opinion it is a delta

PB put the overlay in thread AR13098.

N.

 

[Newbie]

Now an M1.7 from region 3098! BTW Solen had it listend as beta gamma delta last time I looked!

[Solarflaretracker200]

Huh. This region got recently interesting and is now a BG

(Beta Gamma)

[MinYoongi]

17 minutes ago, Newbie said:

Now an M1.7 from region 3098! BTW Solen had it listend as beta gamma delta last time I looked!

Solen only updates once a day, so thats not "reliable" since Deltas can form and die quicker than Solen is updated. The Delta you and @Philalethes Bythos pointed out seems to still be there though! And yep, first M Class 🥰 Lots of fireworks in that region

[Newbie]

 

5 minutes ago, MinYoongi said:

Solen only updates once a day, so thats not "reliable" since Deltas can form and die quicker than Solen is updated. The Delta you and @Philalethes Bythos pointed out seems to still be there though! And yep, first M Class 🥰 Lots of fireworks in that region

I didn't rely on Solen, I, and similarly PB had already formed our opinion as per the post in 3098.

Solen was updated at some stage it's more like, well they agree eventually. Lol

N.

[WildWill]

Howdy All Y'all!

You guessed it! Time for another round of "show me the deltas! We haven't had a really good AR with deltas for a while! 
 

Those of ya who are more experienced, show us, who are not as seasoned.  I expect with this region, we might get to play the game a few times as it makes its way around earth side! 
 

Here we go! Can you show me the deltas??

 

It sure does look pretty coming around from the limb!  Heading out for my near real-time view! (8 min 20 sec delayed ) One thing I've learned over the last year is that picking out "delta" spots is an art form. So, I'm very interested to see differences between what each artist presents.

All y'all have ya a great day! 

WnA