AR 3256

[Landon Moeller]

On 3/18/2023 at 6:00 PM, Christopher S. said:

It doesn't in the sense that you are asking, no. Coronal Holes blow material and gasses away from the Sun, inhibiting the formation of sunspots within and generally around to a lesser extent, as this outflow can be considered a distinct, stable region of the Sun in this regard. They are part of the dynamo effect which gives us the IMF, playing a different role in Space Weather entirely. Check this: https://ntrs.nasa.gov/citations/19920064048

In essence CHs reduce the probability of front-side flaring by virtue of taking up space which could be populated by sunspots, and do not amplify ARs adjacent to them. These are distinct forces that may complement one another, but do not act as catalysts for flaring - that's up to the AR itself.

Referring to said coronal hole. This morning, NOAA SWPC introduced G2 (Moderate) into their forecast for the Saturday UTC day (25th). This means effects from the large CH may arrive as early as late Friday night. 

[Trestan]

On 3/18/2023 at 7:00 PM, Christopher S. said:

On 3/18/2023 at 6:40 PM, Strom said:

Does the coronal hole just to the west of 3256 have any impact on the probability of bigger flares from 3256?   I guess what I’m asking is when a significant sunspot is also near a coronal hole, is the probability of activity increased?

It doesn't in the sense that you are asking, no. Coronal Holes blow material and gasses away from the Sun, inhibiting the formation of sunspots within and generally around to a lesser extent, as this outflow can be considered a distinct, stable region of the Sun in this regard. They are part of the dynamo effect which gives us the IMF, playing a different role in Space Weather entirely. Check this: https://ntrs.nasa.gov/citations/19920064048

In essence CHs reduce the probability of front-side flaring by virtue of taking up space which could be populated by sunspots, and do not amplify ARs adjacent to them. These are distinct forces that may complement one another, but do not act as catalysts for flaring - that's up to the AR itself.

This association between AR activity and proximity to CHs was recently investigated statistically in "Does Nearby Open Flux Affect the Eruptivity of Solar Active Regions?" (DeRosa & Barnes 2018) published in the ApJ. Their results actually suggest that "X-class flares are more likely to be eruptive [result in a CME] when they occur in locations with access to open flux" (i.e., coronal holes) and qualifies this by stating that access to open flux is "neither a necessary nor a sufficient condition for a flare to result in an eruption." Of course this statistical evidence should be taken with a grain of salt, and I suggest reading the paper in its entirety to understand the specific shortcomings. Furthermore, this is just one paper, and additional research will need to be conducted in order to provide a more definitive answer to the question of their association.

Regardless, the rationale for why an AR's proximity to a CH may affect associated flare eruptivity as previously described is fairly intuitive. It goes (very roughly) as follows. An AR close to a CH will have better access to the CH's open flux that leads out into interplanetary space. Therefore, any ejecta trying to escape this AR will have a nearly direct path to escape from the corona. On the other hand, an AR far from any CH will have more overlying closed magnetic fields that may confine any potential ejecta.

I hope this helps.

[KW2P]

On 3/18/2023 at 2:34 AM, Cronus said:

Seems to me the sun needs a few more satellites observing it on the far side. As a concerned citizen, I prefer to know these things rather than guess. Solar research needs significantly more funding.

Indeed. I've lamented this myself. Were I a multi-billionaire I'd do something about it. Get the Stereo plan fixed and going again. And then tackle a farside satellite (do-able but not easy).  I wonder if L3 is usable. It exists but maybe the gravitational fields are too weak to be useful.

[Philalethes]

Some hints of a small delta forming:

[Tormentius]

Hey guys, this region let off a C4.6 a few hours ago. The NOAA report says that they need to model and see if there is an Earth directed component. Granted it’s pretty far to the west but I just wanted to hear your thoughts on the CME they think is associated with this event

[Jesterface23]

4 hours ago, Tormentius said:

Hey guys, this region let off a C4.6 a few hours ago. The NOAA report says that they need to model and see if there is an Earth directed component. Granted it’s pretty far to the west but I just wanted to hear your thoughts on the CME they think is associated with this event

Possibly an glancing blow Earth directed component to it, but hard to tell. I wouldn't expect an arrival.

[Philalethes]

Boom.

Looks very impulsive from the flux.

Peak:

[Jesterface23]

Right where it's expected to happen. Doesn't look like there is much of a CME out of it at least.

[Philalethes]

10 hours ago, Jesterface23 said:

Right where it's expected to happen.

And again just now. The limb of disappointment strikes once more. Just a small M-flare this time it seems, but with the low activity levels recently it's worth noting, I suppose.

[Hagen72]

Nevertheless finally the Sun is awakened from March-noon-nap.

[Philalethes]

Another weak M-flare; looks a bit more eruptive this time, still hard to tell.

[Sam Warfel]

This one looked very pretty afterwards 

[mozy]

M 5.4 flare with what looks like a fairly fast CME was produced.

Edited March 30, 2023 by mozy

[Hagen72]

Thats it and it looks nice...