Unspecified geomagnetic activity

[Philalethes]

13 minutes ago, Jesterface23 said:

The filament CME is spotted in C2 imagery before the far side event, but looks to be more eastward. At this point it is a very clear SIR. The CIR started back around /05 17:00Z going down to favorable conditions with velocities near 330km/s. The SIR arrived at /06 00:30Z with low temperatures. The HSS transition may have begun around /06 04:00Z, but had clearly entered by /06 06:30Z with the temperature and velocity spike and we currently continue to be in a CIR/HSS transition zone. I see no signs of a CME arrival

Sounds reasonable. I'm certainly no CME expert, but at least if I understand it somewhat right the eventual arrival of the flux rope would cause a much more clear structuring of the IMF than we're seeing now.

That being said, I'm wondering: are there any clear signs to watch out for to distinguish the shock formed by a CIR/SIR and the shock at the boundary of the flux rope of a CME? As far as I understand these typically manifest themselves in similar ways, since they're essentially the solar wind being compressed. In this sense I'd expect e.g. a glancing blow from a CME, where we'd experience a prolonged shock, to be similar to that of a CIR/SIR, but I would guess there does exist some notable differences to look for.

[Jesterface23]

24 minutes ago, Philalethes said:

Sounds reasonable. I'm certainly no CME expert, but at least if I understand it somewhat right the eventual arrival of the flux rope would cause a much more clear structuring of the IMF than we're seeing now.

That being said, I'm wondering: are there any clear signs to watch out for to distinguish the shock formed by a CIR/SIR and the shock at the boundary of the flux rope of a CME? As far as I understand these typically manifest themselves in similar ways, since they're essentially the solar wind being compressed. In this sense I'd expect e.g. a glancing blow from a CME, where we'd experience a prolonged shock, to be similar to that of a CIR/SIR, but I would guess there does exist some notable differences to look for.

A sheath shock would precede the flux rope. To cover flux ropes real quick, they would normally have lower temperatures and proton densities once they've entered. The sheath will have higher temperatures similar to CH HSS, but are more dense. For this SIR the main warning sign was the temperatures well below 100000 K. I believe the velocities were somewhere near the upper limit for SIRs, this one peaking at around 430km/s.

Say we were in solar wind velocities of 400km/s and slightly higher temperatures, I don't know how different things would be. A SIR may not form or parameters may be too gradual to notice much of a difference. Not too sure.

[Philalethes]

4 minutes ago, Jesterface23 said:

A sheath shock would precede the flux rope. To cover flux ropes real quick, they would normally have lower temperatures and proton densities once they've entered. The sheath will have higher temperatures similar to CH HSS, but are more dense. For this SIR the main warning sign was the temperatures well below 100000 K. I believe the velocities were somewhere near the upper limit for SIRs, this one peaking at around 430km/s.

Say we were in solar wind velocities of 400km/s and slightly higher temperatures, I don't know how different things would be. A SIR may not form or parameters may be too gradual to notice much of a difference. Not too sure.

Right, I was primarily talking about the shock, since a flux rope itself would be relatively easy to distinguish as far as I'm aware. The question was how to distinguish that sheath shock from a SIR, and I think I understand what you're saying: the sheath shock of a CME will typically have higher temperatures than a SIR.

In other words, if you see a gradually rising temperature, that's indicative of an incoming SIR and ensuing HSS, whereas an abrupt rise in temperature would be indicative of a sheath shock; correct me if I'm wrong.

[Jesterface23]

21 minutes ago, Philalethes said:

The question was how to distinguish that sheath shock from a SIR, and I think I understand what you're saying: the sheath shock of a CME will typically have higher temperatures than a SIR.

Yes

21 minutes ago, Philalethes said:

In other words, if you see a gradually rising temperature, that's indicative of an incoming SIR and ensuing HSS, whereas an abrupt rise in temperature would be indicative of a sheath shock; correct me if I'm wrong.

I think the CH gradual rise in the temperature would be more of the HSS entry. CME sheath shocks may arrive with a high temperature and still gradually rise. This SIR had a little spike in temperature on arrival, but remained fairly consistently low until the HSS arrival. The HSS temps peaked ~9x higher than the SIR.

[Guest]

Slight impact in process , in geomagnetic disturbance :

Edited May 7, 2023 by Jhon Henry Osorio Orozco
Mas eventos

[Isatsuki San]

26 minutes ago, Jhon Henry Osorio Orozco said:

Ligero impacto en proceso, en perturbación geomagnética :

If I arrive 6 hours before the NOAA forecast to be an indirect hit, the density is almost

40 p/cm 

and there came the impact to Dscovr

16 bt
and 11 bz to north

Edited May 7, 2023 by Isatsuki San

[Jesterface23]

It is possible there may be some influences from the CME from the 4th on the center disk CH. We are going now in a CIR to HSS transition, so it is hard to tell currently.

Edited May 7, 2023 by Jesterface23

[Isatsuki San]

18 minutes ago, Jesterface23 said:

It is possible there may be some influences from the CME from the 4th on the center disk CH. We are going now in a CIR to HSS transition, so it is hard to tell currently.

for me the density was the coronal hole, and the impact of 16 bt at 11 bz north, was the cmeI don't know if you think the same because the temperature also rose during that impact

[Jesterface23]

1 minute ago, Isatsuki San said:

for me the density was the coronal hole, and the impact of 16 bt at 11 bz north, was the cmeI don't know if you think the same because the temperature also rose during that impact

The density dropped as temperature spiked in this case, along with a little rise in the velocities so far. CH CIRs or SIRs are the higher densities. CH HSS are the higher temperatures and velocities.

[Isatsuki San]

31 minutes ago, Jesterface23 said:

La densidad cayó a medida que la temperatura se disparó en este caso, junto con un pequeño aumento en las velocidades hasta el momento. CH CIR o SIR son las densidades más altas. CH HSS son las temperaturas y velocidades más altas.

it seems that spaceweatherlive says that if it was a cme,

[Jesterface23]

6 minutes ago, Isatsuki San said:

it seems that spaceweatherlive says that if it was a cme,

Ehhhh, the SWPC issued a geomagnetic sudden impulse warning. Friday's CME should still be coming and have a more clear arrival.

[Isatsuki San]

3 hours ago, Jesterface23 said:

Ehhhh, the SWPC issued a geomagnetic sudden impulse warning. Friday's CME should still be coming and have a more clear arrival.

It seems that this time if it is the cme or the second cme?

[mozy]

Can it hit already... Getting dark & we have clear skies..

[Jesterface23]

23 minutes ago, Isatsuki San said:

It seems that this time if it is the cme or the second cme?

2 CMEs launched and would have merged around the same time of /05 08:00Z and that looks to be still coming.

The higher proton density seems to act as a sponge and a wall for the EPAMp. Most of the wall dropped about 5 hours ago, so now it is just a waiting game.

[mozy]

Oh well too late for me to have a chance now, time to wait for autumn for the next chance 😅

[Philalethes]

7 minutes ago, mozy said:

Oh well too late for me to have a chance now, time to wait for autumn for the next chance 😅

If the latest trends continue there should definitely be a lot of activity then. At least looking back several years it's been almost like clockwork with clear peaks at the equinoctes and equally clear troughs at the solstices, with few exceptions.

[mozy]

3 minutes ago, Philalethes said:

If the latest trends continue there should definitely be a lot of activity then. At least looking back several years it's been almost like clockwork with clear peaks at the equinoctes and equally clear troughs at the solstices, with few exceptions.

Yeah we'll see, late august & march have been the lucky months for me, It's usually always cloudy & windy in October / November.. It's far too bright most of the day now, at around 10:50 PM today it was still not dark enough at the northern direction & it's getting bright out after 2:45 AM already.

Hoping activity really picks up after the summer  I've yet to see a really good display that goes on for long, only experienced few good/decent substorms for 5-10 minutes.

Edited May 7, 2023 by mozy

[3gMike]

41 minutes ago, mozy said:

Yeah we'll see, late august & march have been the lucky months for me, It's usually always cloudy & windy in October / November.. It's far too bright most of the day now, at around 10:50 PM today it was still not dark enough at the northern direction & it's getting bright out after 2:45 AM already.

Hoping activity really picks up after the summer  I've yet to see a really good display that goes on for long, only experienced few good/decent substorms for 5-10 minutes.

Not quite the same experience but can you enjoy Noctilucent clouds during the summer nights?

[mozy]

11 minutes ago, 3gMike said:

Not quite the same experience but can you enjoy Noctilucent clouds during the summer nights?

Yes, I see them every year, one day in 2015 was so spectacular I would almost say it was better than the northern lights I've experienced, didn't feel real at all.

Here are 2 photos from that night. (my profile photo literally)

Edited May 7, 2023 by mozy

[Isatsuki San]

in a few minutes we will have a cm come to earth?

[Guest]

Impact in process , in geomagnetic disturbance : 

Edited May 7, 2023 by Jhon Henry Osorio Orozco

[Jesterface23]

6 minutes ago, Jhon Henry Osorio Orozco said:

Impact in process , in geomagnetic disturbance : 

Not quite how it works. Watch the Bt, not Bz.

45 minutes ago, Isatsuki San said:

in a few minutes we will have a cm come to earth?

The red 47-48KeV line is already fairly high, so I'm not sure how much of a warning we will get. If it spikes before arrival we could get within an hour heads up for L1.

[Jesterface23]

Well, the CH HSS is fairly strong now. If there is a CME still coming, the odds of it arriving will decline as time goes on. The main hope now is that the lower EPAMp lines are rising, but that could also be the new CME.

[Jesterface23]

ACE showed a good sign of a possible flux rope back around 03:00Z, so the CME may have arrived embedded the HSS at some point.

[Isatsuki San]

24 minutes ago, Jesterface23 said:

ACE mostró una buena señal de una posible cuerda de flujo alrededor de las 03:00Z, por lo que la CME puede haber llegado incrustada en el HSS en algún momento.

And what do you think about the epam data?