Sometimes i get a random obscure space weather question, and think "this is probably too small to make a thread over"... Well here we are, I made a thread for those things- for the other people I assume are in the same mindset as I. (Also a safe place for ameturs to ask more advanced questions)

I have a question that one of our sharper people may be able to answer in easily understandable terms.    I am aware that most if not all flares release some protons initially or a pulse so to speak.  Then typically we have about a 45 minute to an hour delay before the main event arrives.  Then depending on the speed of the CME we have anywhere from 14 hours ( record) to three or four days or so before the actual CME arrives  

What puzzles me is why the intervening proton stream is slower than the initial proton pulse we may register here on earth.  To further clarify:  A proton event seems to contain three distinct elements within it.   I have been thinking about this in the intervening hours and might be incorrect in my assumption of initial bursts.  These may be entirely electrons.  If so, I wonder if this may be the answer.  Tnx. Mike   Btw. Philalethes acknowledged my realization during a pm exchange of the Type IV broadband radiation pulse as being from electrons hitting the solar corana.  So no protons were killed. 🤣🤣🤣

Edited November 2, 2024Nov 2 by hamateur 1953
Clarity I hope.

would solar flares show up at 3650 angstrom bandpass

 

17 hours ago, hamateur 1953 said:

I have a question that one of our sharper people may be able to answer in easily understandable terms.    I am aware that most if not all flares release some protons initially or a pulse so to speak.  Then typically we have about a 45 minute to an hour delay before the main event arrives.  Then depending on the speed of the CME we have anywhere from 14 hours ( record) to three or four days or so before the actual CME arrives  

What puzzles me is why the intervening proton stream is slower than the initial proton pulse we may register here on earth.  To further clarify:  A proton event seems to contain three distinct elements within it.   I have been thinking about this in the intervening hours and might be incorrect in my assumption of initial bursts.  These may be entirely electrons.  If so, I wonder if this may be the answer.  Tnx. Mike 

The dynamics of how protons propagate through the heliosphere are quite complex, so take whatever I say here with a grain of salt, but I'm not so sure about that "initial burst" assumption either. Maybe I just haven't paid enough attention to SPEs, but it seems to me the general pattern is typically more that the particles at different energies initially rise to a peak over some time (different for the different energies), even though that rise might be a bit chaotic and "jagged" early on. Maybe the "initial burst" might just be due to that early irregularity, i.e. some of the highest-energy ones that end up in a connecting trajectory early on more due to being "lucky", before diffusion and other statistical processes take over to smooth out the rise and subsequent fall. Seems plausible to me, at least.

And another question, a more useful one, though I feel embarrased for asking- when a sunspot does a long duration solar flare, and produces a CME, why does the sunspot sometimes lose all of its complexity immediately, and other times appear unphased

I have a question about aurora colours, sometimes the green goes above the red, why does it happen? Isn't the red supposed to be in the higher layer? 

When a filament erupts from the sun and makes a CME does the sun get a bit smaller 

50 minutes ago, Manuel said:

I have a question about aurora colours, sometimes the green goes above the red, why does it happen? Isn't the red supposed to be in the higher layer? 

Green is made by oxygen gas interacting with the CME. Nitrogen gas is lighter than oxygen, do it is normally above oxygen. But due to atmosphere altitudes, they can be seen at different perspectives, and sometimes there is atomic oxygen higher in the atmosphere, or if it hits the ozone layer (O³). Other. Other colours include helium - orange/white, neon - red/orange, argon - lavender and krypton - gray/green.

1 minute ago, Solarflare said:

When a filament erupts from the sun and makes a CME does the sun get a bit smaller 

Yes, but the core only gets smaller, as the nuclear fusion inside the core continues the convection inside until it burns out. This will only be a very little every time, and not noticeable enough.

59 minutes ago, Mantis said:

And another question, a more useful one, though I feel embarrased for asking- when a sunspot does a long duration solar flare, and produces a CME, why does the sunspot sometimes lose all of its complexity immediately, and other times appear unphased

The sunspot could have used it's full complexity and lost it in a massive CME, or it's magnetically caged sometimes, reabsorbing the released plasma.

2 hours ago, Solarflare said:

When a filament erupts from the sun and makes a CME does the sun get a bit smaller 

Well, it naturally does lose that mass, but the average mass of a CME has been estimated to ~2e12 kg, and the Solar mass is ~2e30 kg; so in other words, a CME constitutes roughly a billionth of a billionth (a quintillionth) of the Solar mass.

3 minutes ago, Philalethes said:

Well, it naturally does lose that mass, but the average mass of a CME has been estimated to ~2e12 kg, and the Solar mass is ~2e30 kg; so in other words, a CME constitutes roughly a billionth of a billionth (a quintillionth) of the Solar mass.

Is it fair to assume that the suns gravitational pull captures at least as much as the sun loses through CME? So is the sun actually shrinking or growing in mass? Even if it’s only measured in the billions of a percent? 

4 minutes ago, WhereingtonEvent said:

Is it fair to assume that the suns gravitational pull captures at least as much as the sun loses through CME? So is the sun actually shrinking or growing in mass? Even if it’s only measured in the billions of a percent? 

I don't think that's fair to assume, no. It might sound reasonable at first, but most material will simply orbit at various distances despite the gravity itself being so strong, only a small fraction will have the right trajectory (like sungrazer comets, but it applies to smaller particles too). Taking the extent all the way out to the F-corona where smaller dust particles get trapped (those that come closer get evaporated, but still add their mass) as the Solar mass, then there's a quick back-of-the-envelope calculation made here in the answer by Samvel Ter-Antonyan, estimating the rate of mass captured to ~100 tonnes/s.

In contrast, it's losing roughly 4.3 Mt (megatonnes, million tonnes) of mass in the form of radiation every single second, and about a third of that in the form of Solar wind on average as well, so around 5.7 Mt lost every second in total on average; going by the above estimate, it's losing almost 60,000 times more mass every second than it's gaining.

As a fraction of the total mass this is still quite small, though, as it corresponds to just ~1e-13 of the Solar mass each year, i.e. a tenth of a trillionth.

I guess I didn't quite address the question about the mass lost to CMEs specifically, since I assumed you were thinking of mass lost in general. Without too many details we can assume something like 1000 CME/year on average, so going by the earlier estimate of ~2e12 kg/CME, then we get ~2e12 t/year, which is ~63,000 t/s, still over 600 times as much mass lost through CMEs alone as that gained. Interestingly this also tells us that CMEs only make up about a hundredth of the mass lost, and since a quarter of that total mass lost is Solar wind, then it means that ~25 times more mass is lost to Solar wind than to CMEs.

why do geomagnetic storms still happen during solar minimum?

  

3 hours ago, YourLocalCapybara2 said:

why do geomagnetic storms still happen during solar minimum?

(mainly) CH HSS + (rarely) small sunspots which happen to make CMEs (and sometimes, even more rare, active sunspots)

 

(correct me if i am wrong)

Edited November 2, 2024Nov 2 by Mantis
forgot to insert quote AGAIN

I'll ask here, because I can't find a proper answer anywhere. What's the X-ray saturation limit for working GOES satellites? Can the current technology (GOES 16, 18, 19) precisely measure >X20 flares, what couldn't be done in SC23?

I have a question whit the goes X-ray flux on the goes X-ray flux there is a GOES 18 long and short what is the short because the GOES 18 short shows it at a B or A flare while the long is at C flare what’s the purpose for the GOES 18 short and why does it show a b or A flare while the goes 18 long is at C flare 

16 hours ago, Manuel said:

I have a question about aurora colours, sometimes the green goes above the red, why does it happen? Isn't the red supposed to be in the higher layer? 

Was that when a SAR arc was happening? If yes, the green could be a proton aurora -- read more in the link

 

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022JA030570

 

3 hours ago, libmar96 said:

I'll ask here, because I can't find a proper answer anywhere. What's the X-ray saturation limit for working GOES satellites? Can the current technology (GOES 16, 18, 19) precisely measure >X20 flares, what couldn't be done in SC23?

I was wondering the same thing a while ago! The instrument details for the GOES-R series can be found in the data book here; I'm not 100% sure there's no upgrade for GOES-U, but it's reasonable to assume they're all more or less the same when it comes to the trusty old X-ray sensor (XRS). Towards the very end there's a section with the design specifications for the instruments, including EXIS (which the XRS is part of), under "EXIS Design". There it says the dynamic range is actually only up to 1e-3 W/m², corresponding to X10. To me this seems rather odd, because in the data book for the GOES-N series the XRS-B sensor (which measures the longwave flux) is listed as having a dynamic range up to twice that at X20 (I believe more precisely the saturation point was at X17.4).

There are three possible explanations that I can think of for this:

1. The XRSs of GOES-R series satellites are in fact worse than those of GOES-N series ones; I personally find this unlikely, especially after experiencing saturation in 2003.
    
2. What's listed is just roughly the order of magnitude, leaving out the significand (i.e. it could possibly have a range up to X30, or X50, or X80, and so on). Seems like a bit of an oversight to me, especially considering how it's explicitly listed in the previous data book.
    
3. What's listed is only for the XRS-A sensor (which measures the shortwave flux), with no specific entry for the XRS-B one. This seems like a possibility due to how the two are not just listed separately in the previous data book, but that their ranges are also different. There XRS-A stretches over an equally large range, but starts and ends at only a fourth of the values of XRS-B. In other words, if this is indeed the case and we assume the same to be true here, then we could expect the maximum flux for XRS-B to be around X40.

Not sure which of these, if any of them, is correct. Seems a bit sloppy in any case, but to me the second or third explanations (or a combination thereof) seem the most likely. Digging a bit more into it I found the document describing the early specifications and design of the GOES-R series here. Indeed it says that the requirement for the XRS-B sensor is up to 4e-3 W/m², i.e. X40; it does however start at the same value listed in the data book, so can't tell if it's really the second or third explanation going on here.

Can't rule out the first explanation either, they could've scrapped those requirements and just made it worse, heh; but I doubt that. I think to get 100% clear answer to this we'd have to ask someone more intimately involved in the process of designing and producing it, but in the meanwhile I think the X40 estimate is a reasonable assumption.

If there is a big coronal hole on the sun does it make the sun dimmer and less intense on the surface of earth?

2 hours ago, Solarflare said:

I have a question whit the goes X-ray flux on the goes X-ray flux there is a GOES 18 long and short what is the short because the GOES 18 short shows it at a B or A flare while the long is at C flare what’s the purpose for the GOES 18 short and why does it show a b or A flare while the goes 18 long is at C flare 

Each of the satellites have two different sensors, one for measuring X-rays with longer wavelengths (0.1-0.8 nm) and one for X-rays with shorter wavelengths (0.05-0.4 nm). There is some overlap in the range, but generally speaking there will be less flux density in the shorter wavelengths; while each X-ray photon of those shorter wavelengths has a higher energy than those with longer, there are fewer of them (luckily for us and the universe, so we avoid the ultraviolet catastrophe).

The flare classes are defined by the longwave flux densities, based on how frequently they occur, so it doesn't really make that much sense to think of the shortwave fluxes adhering to the same classes.

3 hours ago, YourLocalCapybara2 said:

why do geomagnetic storms still happen during solar minimum?

 

8 minutes ago, Mantis said:

  

(mainly) CH HSS + (rarely) small sunspots which happen to make CMEs (and sometimes, even more rare, active sunspots)

 

(correct me if i am wrong)

Geomagnetic storms are classified as either "recurrent" or "non-recurrent." Recurrent storms, corresponding with the Sun's rotation, occur every 27 days. They are triggered by the Earth's encounter with the southward IMF, when high-pressure regions are formed by the interaction of low and high speed solar wind streams that co-rotate with the Sun.

The WSA-Enlil shows this. Look for the green and yellowish bands rotating the sun like a fan l.

These recurring storms most frequently occur during the solar minimum, the declining phase of the solar cycle. Non-recurring storms frequently occur during the solar maximum, when the solar cycle is at a high peak. These storms are caused by coronal mass ejections (CMEs) (a collection of charged particles) and, typically, the CME's encounter with interplanetary shock waves. (The ones we go crazy about after a X flare.)

Why does the sun looks like it has a smile? 

2 hours ago, Pleroma said:

Why does the sun looks like it has a smile? 

Good question, it looks confused on the HMI Intensitygram and the Magnetogram.

AIA 097 and AIA 131 it looks like it's raising its eyebrows and looking confused

AIA 193 and AIA 211, it looks like it's rolled onto its side

AIA 304 looks like it's not impressed - _ - tired ~_~ and the sun is on its side again |:

AIA 355 looks shocked.

And AIA 1600 and AIA 1700 look like a pig.

SDO created the new Mona Lisa.

Edited November 2, 2024Nov 2 by Zhe Yu

10 hours ago, YourLocalCapybara2 said:

why do geomagnetic storms still happen during solar minimum?

 

7 hours ago, Mantis said:

  

(mainly) CH HSS + (rarely) small sunspots which happen to make CMEs (and sometimes, even more rare, active sunspots)

 

(correct me if i am wrong)

I was wondering about that too. Like, how did those top 7th and 11th solar flares on record happen in september 2017?

1 minute ago, Bry said:

 

I was wondering about that too. Like, how did those top 7th and 11th solar flares on record happen in september 2017?

You have misunderstood. The highest flare that occurred during the last solar minimum was around the M1 mark, and because of scaling of the x-ray flux, the flares didn't even get recorded as a M class flare from the SWPC. The last solar minimum was from Autumn 2016 to 2020.

5 hours ago, Zhe Yu said:

You have misunderstood. The highest flare that occurred during the last solar minimum was around the M1 mark, and because of scaling of the x-ray flux, the flares didn't even get recorded as a M class flare from the SWPC. The last solar minimum was from Autumn 2016 to 2020.

It is easy for many to misunderstand this!   It drove me nutso at the time when Jester was working on revisions of the database as I remember!!   I remember thinking like Huh???  Why??? Then finally a week later no less after reading up on it, I understood why.   Cuz I knew the dude was sharper than me, I trusted that even if I didn’t understand it, he most certainly did and it would work out well for all in the end anyway 🤣🤣🤣

Edited November 2, 2024Nov 2 by hamateur 1953
Wasn’t fully awake. 😇