Jul 2012 CME impact on Stereo-A

[tniickck]

as you know (or don't), famous CME from 23 Jul 2012 from the farside impacted Stereo-A. is there any data from there with solar wind speed, density etc. ? it would be nice to see and compare

[Marcel de Bont]

https://stereo-ssc.nascom.nasa.gov/browse/2012/07/23/insitu.shtml and https://stereo-ssc.nascom.nasa.gov/browse/2012/07/24/insitu.shtml Some wild wild data. Solar wind data got knocked out it seems by the proton storm I assume.

[Vancanneyt Sander]

During that event, Stereo A was in a position to receive the hit from this CME (and yes the satellite survived that event).

impact speed around 1.100-1.200km/sec with a strong northward (86nT) in the beginning and strong southward directed field (max -50nT) later on. Dst wise -267 which would be a major geomagnetic storm and not an alarmingly large space weather threat. But this is based on beacon data of Stereo.

later investigation on the event it arose to the PLASTIC investigation team that for high solar wind speeds combined with the high energy particle backgrounds the actual solar wind speeds would be underestimated. So after recalculation it became:

which results in a much stronger storm that would be the strongest in recent history (so up as strong as the 1989 one).

PS: It should be noted that the velocity of the interplanetary shock after the large flare on August1972 was even larger, ~2850 km/s. But IMF was northward (73nT) so no major geomagnetic storm then.  

[tniickck]

1 hour ago, Vancanneyt Sander said:

During that event, Stereo A was in a position to receive the hit from this CME (and yes the satellite survived that event).

impact speed around 1.100-1.200km/sec with a strong northward (86nT) in the beginning and strong southward directed field (max -50nT) later on. Dst wise -267 which would be a major geomagnetic storm and not an alarmingly large space weather threat. But this is based on beacon data of Stereo.

later investigation on the event it arose to the PLASTIC investigation team that for high solar wind speeds combined with the high energy particle backgrounds the actual solar wind speeds would be underestimated. So after recalculation it became:

which results in a much stronger storm that would be the strongest in recent history (so up as strong as the 1989 one).

PS: It should be noted that the velocity of the interplanetary shock after the large flare on August1972 was even larger, ~2850 km/s. But IMF was northward (73nT) so no major geomagnetic storm then.  

thank you so much

[SpaceWeather5464]

4 hours ago, Vancanneyt Sander said:

During that event, Stereo A was in a position to receive the hit from this CME (and yes the satellite survived that event).

impact speed around 1.100-1.200km/sec with a strong northward (86nT) in the beginning and strong southward directed field (max -50nT) later on. Dst wise -267 which would be a major geomagnetic storm and not an alarmingly large space weather threat. But this is based on beacon data of Stereo.

later investigation on the event it arose to the PLASTIC investigation team that for high solar wind speeds combined with the high energy particle backgrounds the actual solar wind speeds would be underestimated. So after recalculation it became:

which results in a much stronger storm that would be the strongest in recent history (so up as strong as the 1989 one).

PS: It should be noted that the velocity of the interplanetary shock after the large flare on August1972 was even larger, ~2850 km/s. But IMF was northward (73nT) so no major geomagnetic storm then.  

If it was aimed at earth would it really have caused issues to our power grids on earth? NASA said that if it had hit earth we would still be picking up the pieces today 

https://science.nasa.gov/science-research/planetary-science/23jul_superstorm/

 

[Orilander]

18 minutes ago, SpaceWeather5464 said:

If it was aimed at earth would it really have caused issues to our power grids on earth? NASA said that if it had hit earth we would still be picking up the pieces today 

https://science.nasa.gov/science-research/planetary-science/23jul_superstorm/

 

It might have been possible, depending on how strong it would have been had it hit Earth. Honestly this feels a bit scaremonger-y, and from NASA of all people. Again, I'm not a big expert on this type of possible scenario (someone else can feel this in better detail), but if we were able to survive the 2003 Halloween storms with little issue, I don't think we'd have a major issue here. Sure, it might affect some areas more than others, but I don't think it'd be as bad as is being described here.

If nothing else, it'd certainly give people the ammo they needed for "End of Days" theories; and definitely would have driven the whole 2012 conspiracy regardless.

Edited November 24, 2023 by Orilander

[Vancanneyt Sander]

11 uren geleden, SpaceWeather5464 zei:

If it was aimed at earth would it really have caused issues to our power grids on earth? NASA said that if it had hit earth we would still be picking up the pieces today 

https://science.nasa.gov/science-research/planetary-science/23jul_superstorm/

 

No, based on stereo data not, but only if Bz was stronger southward and if it was around equinox (worst case scenario)

[Patrick P.A. Geryl]

5 uren geleden, Vancanneyt Sander zei:

No, based on stereo data not, but only if Bz was stronger southward and if it was around equinox (worst case scenario)

What about the farside storm from July 2017? About same strength as 2012.

[Vancanneyt Sander]

21 minuten geleden, Patrick P.A. Geryl zei:

What about the farside storm from July 2017? About same strength as 2012.

That event (double CME impact) was calculated to have a Dst index range between -330 and -590nT which is top 20 superstorms since 1932 and close to the 1989 event. Solar wind speed was also lower than 2012 event making it less severe.

[tniickck]

2 hours ago, Patrick P.A. Geryl said:

What about the farside storm from July 2017? About same strength as 2012.

wow, didn't know about that

 

are there any other enormously fast farside CMEs? 

Edited November 25, 2023 by tniickck

[Vancanneyt Sander]

40 minuten geleden, tniickck zei:

are there any other enormously fast farside CMEs? 

Likely yes but these two are the only major events when we had a satellite monitoring the farside where data could be collected.

[Jesterface23]

1 hour ago, tniickck said:

are there any other enormously fast farside CMEs? 

The July 23rd, 2017 occurred near the east limb for SA, then there is a somewhat similar CME that occurred off the west limb for SB on March 7th, 2012. Noting both were glancing blows for each satellite though with travel times of around 37 hours to them. Can't forget the September 10th, 2017 CME off the west limb of L1 arriving around 51 hours after launch.

The July 23rd, 2012 CME does have a weaker twin as well. It launched on November 7th, 2013 and the main bulk impacted SB after around 27 hours of travel.

Edited November 25, 2023 by Jesterface23

[SpaceWeather5464]

3 hours ago, tniickck said:

wow, didn't know about that

 

are there any other enormously fast farside CMEs? 

On March 13, 2023 there was a farside CME that left the sun faster than 3000 km/s.

On March 7, 2011 there was a farside CME that left the sun traveling some 2200 km/s.

On November 4th, 2003 there was a farside CME that left the sun at about 2300 km/s.

On September 10, 2017 there was a farside CME that left the sun at the speed of some 2000 km/s to 3500 km/s.

On January 23, 2012 there was a CME that left the sun at about 2200 km/s.

On March 7th, 2012 there was a CME that also left the sun at about 2200 km/s.

These are all the fast farside CME's that I am aware of but there could be more.

 

 

 

10 hours ago, Vancanneyt Sander said:

No, based on stereo data not, but only if Bz was stronger southward and if it was around equinox (worst case scenario)

That makes sense because the Carrington Event happened during September which is a equinox month, While the 1972 solar storm which was faster than the Carrington event yet less weaker when it hit the magnetic field happened during August when the magnetic field is stronger.

Edited November 25, 2023 by SpaceWeather5464

[tniickck]

just found an enormous cme from 16th Jul 2023

SolO measured it as a X8.1 flare

has a younger brother which left the sun on 17th Jul and was triggered by X9 and following M3 flare

Edited December 27, 2023 by tniickck

[Jesterface23]

1 hour ago, tniickck said:

just found an enormous cme from 16th Jul 2023

The power of an inaccurate model run.

From SA, there was a CME that launched on July 17th and arrived on the 20th. Then another launching early on the 19th and arriving late on the 20th. After that the CME from the 23rd happened.

Edited December 27, 2023 by Jesterface23

[tniickck]

4 minutes ago, Jesterface23 said:

The power of an inaccurate model run.

From SA, there was a CME that launched on July 17th and arrived on the 20th. Then another launching early on the 19th and arriving late on the 20th. After that the CME from the 23rd happened.

wasnt it that strong? we got S1 proton event from it and on coronographs it looks impressive

https://cdaw.gsfc.nasa.gov/CME_list/UNIVERSAL_ver1/2023_07/univ2023_07.html look here on "Halo" cmes from 15th to 17th. there were a lot

here it is on Stereo-A

[Jesterface23]

48 minutes ago, tniickck said:

wasnt it that strong? we got S1 proton event from it and on coronographs it looks impressive

That S1/S2 looks to be with the CME from the 17th. It looks like it is possibly a major filament eruption reaching M2.55 and the CME also impacted L1.

Edited December 27, 2023 by Jesterface23

[tniickck]

7 minutes ago, Jesterface23 said:

That S1/S2 looks to be with the CME from the 17th. It looks like it is possibly a major filament eruption reaching M2.55 and the CME also impacted L1.

a unlikely scenario. CME impacted L1 in the evening, but proton event began suddenly right after farside CME. i think there is an obvious connection

[Jesterface23]

1 minute ago, tniickck said:

a unlikely scenario. CME impacted L1 in the evening, but proton event began suddenly right after farside CME. i think there is an obvious connection

Ahhh, welp the topic had me on 2012 and not 2023.

Now I remember when those farside CMEs came up earlier in the year

................

(It looks too similar to past events for me I guess lol)

[hamateur 1953]

As a bit of an aside, the aug 4 1972 event was recently modeled by Tamitha Skov as having been a glancing blow instead of the direct hit I had always assumed it had been.  Apologies if Id misled anyone in the past. It was news to me.  Btw she received a nice award recently too!   Very cool. 

Edited December 27, 2023 by hamateur 1953

[tniickck]

51 minutes ago, hamateur 1953 said:

As a bit of an aside, the aug 4 1972 event was recently modeled by Tamitha Skov as having been a glancing blow instead of the direct hit I had always assumed it had been.  Apologies if Id misled anyone in the past. It was news to me.  Btw she received a nice award recently too!   Very cool. 

can you post a link to this model? and were any other powerful events modeled like 28 Oct 2003 or else

[hamateur 1953]

8 hours ago, tniickck said:

can you post a link to this model? and were any other powerful events modeled like 28 Oct 2003 or else

There isn’t one that I am aware of @tniickck   I saw her displaying it during the four hour class I mentioned in the thread “ Interesting four hour class” here awhile back now.  The thread should still be here in “ other” where I likely posted it earlier.  Checkitout. You will probably be as amazed as I was.  Hopefully you are able to get a decent Russian/English format going.   Mike/Hagrid.   Edit:  The main part of the CME seems to have preceded earth by a bit in our orbit.   Funny. I was going to recheck the moon for that night to see if that wasn’t part of her reason for finding little available public comments….

Edited December 27, 2023 by hamateur 1953
Added stuff

[Philalethes]

@tniickck:

Quote

by images from stereo-a, it was in front of it

Is there any info you could point me to about the flare estimate from that view? I know SA was in front of it, but as far as I know it only has EUVI which doesn't directly measure flare strength; but maybe there are methods to estimate the strength from that.

Quote

nah, not even close: if you take solar system as a large wall clock and put Earth at 12, the flare was at about se ven (it is hard to explained but i hope you got it), just because of the Parker's spiral and the enormous speed and density the CME dived so deep in our direction, but of course didnt hit us

Well, that's even further past the limb, but that's more or less what I meant, i.e. that we wouldn't have been able to measure the flare strength directly with any Earth-facing imagery, so we'd have to rely on SA.

[tniickck]

1 hour ago, Philalethes said:

@tniickck:

Is there any info you could point me to about the flare estimate from that view? I know SA was in front of it, but as far as I know it only has EUVI which doesn't directly measure flare strength

some people measured it by an image. can't tell you more, but on the imagery it for sure doesn't look stronger than X5

[Philalethes]

1 hour ago, tniickck said:

some people measured it by an image. can't tell you more, but on the imagery it for sure doesn't look stronger than X5

I actually delved a bit into it myself to see what I could find, and those findings agree with what you're saying (and also resolves any ambiguity about whether the flare strength was estimated from our view or from the SA imagery).

For you or anyone else interested I first checked the Wikipedia page on the Solar storm where I first found the claim about it being maximum X2.5, which says:

Quote

The eruption emanated from solar active region 11520 and coincided with what was at most an X2.5-class solar flare.

So I checked the citation, and located the full article here, where it says:

Quote

The magnitude of the associated flare on the Sun was estimated (based on EUVI observations) to be at most X2.5 (Nitta et al. 2013), which is not particularly intense compared with the Carrington (>X10) and 2003 November (X28) flares. This is surprising given how extreme the solar wind disturbance was. The July 23 event indicates a “perfect storm” scenario for the formation of extreme events, i.e., a combination of circumstances results in an event of unusual magnitude.

This finally led to the article being cited there, which is titled Soft X-ray Fluxes of Major Flares Far Behind the Limb as Estimated Using STEREO EUV Images, in other words exactly what I was wondering if there existed a way to do; they conclude that their estimates should be fairly accurate for stronger flares (>M4), and list several events in a table there, including the one in question:

Quote

Date        Time      A or B  Location  Est. FGOES     Range
[...]
2012/07/23  02:30:56  A       S15 W133  1.5 * 10^(−4)  M8.2–X2.5

 

Edited February 6 by Philalethes
typo