CME Research Project: 2022

[Jesterface23]

I have an update to my Coronal Mass Ejection research project going into 2022.

My research began back in 2015 attempting to find a new way to predict the arrival time of Coronal Mass Ejections. At the time I only used SOHO LASCO's processed classic blue C3 coronagraph imagery, SOHO and SDO's solar imagery for the time of launch, arrival times provided by different satellites at L1, and a ruler hand held onto my monitor to make sure points of observation were nearly 180 degrees apart in the coronagraph imagery.

The first image below is where a pattern was visible, two curved lines can be made out. Expecting only one line at the time I crossed out points and I ended up going through imagery and data again to create my second and final graph on paper to date.
Graph 1: https://drive.google.com/file/d/1b-bZnwffapc9e2JY5KVRy5WlOgBjcsI-/view?usp=sharing
Graph 2: https://drive.google.com/file/d/1EFO3I1sCJH5uTKV3Q49Ez7h8in2y5kY4/view?usp=sharing
 - X-axis in minutes

Coming into 2022 I have a new tool that I will call CView to help me track and analyze CMEs in SOHO's C3 imagery and both STEREOs C2 imagery. I have an example of CView in use below. In using CView, the first goal is to get a better understanding of CME structure viewed through coronagraph imagery. The second goal is to create another graph for arrival time forecasting to have a solid foundation for future research and active theories based on the arrival time prediction method.
CView: https://drive.google.com/file/d/1uRMP2IwV2PBD9enjlZZj6bahi7Tap2Dw/view?usp=sharing

Although I only made the two graphs above, I did run more calculations with SOHO and used the STEREO satellites imagery as well over the years. Up until September 10th, 2017 I didn't know what the lines on the arrival time prediction graph actually meant. Eventually the only conclusion was that the leading structure in the center and sides can be offset like in the preliminary cross-section graph below. I refer to the center leading section as the Leading Shock and side offset sections as the Secondary Shock.
Cross-Section: https://www.desmos.com/calculator/3jqslv8lzn

Along with the basics of the cross-section, the basics of the arrival time prediction graph became known as well. There are 3 lines, M0, M2, and M3. I named the lines M for Multiplier because a number retrieved from the graph is multiplied by another number to get the estimated travel time of a CME. I have a preliminary arrival time prediction graph below roughly for SOHO C3's imagery at L1 with a formula I created to be similar to the first two graphs above. I will go into more detail about how the Multiplier work next.
Preliminary Graph: https://drive.google.com/file/d/1USTEngoORHx81swztRJpeaTP4I_kArvq/view?usp=sharing
 - X-axis in hours
 - Base formula used: y=cos(pi*x)-(x/sqrt(pi/2))

Now here is how the CME leading structure and arrival time prediction graphs go together and are understood. The M3 line is simple. Looking through coronagraph imagery, the CME is all Leading Shock and I have a cross-section image with 2 examples below. The M2 and M0 lines are where the Secondary Shock is seen in the coronagraph imagery. For both, on one side there is the Leading Shock like with the M3 line, but then there is a decline to the Secondary Shock. For the M2 line the center of the coronagraph imagery is directed Leading Shock while the M0 line has the center of the coronagraph imagery being directed at the Secondary Shock and an example for both are in an image below. Anything below the M0 line and above the M2 line is where the center of the coronagraph imagery is directed on the decline between the Leading and Secondary Shock. Anything below the M3 line is a narrow CME.
M3: https://drive.google.com/file/d/1bAfld7W6i1Fq0SRf9TwE4hl4_qvrYF5y/view?usp=sharing
M2 & M0: https://drive.google.com/file/d/1lRH8VayFqd4n1EWL8LSQ0jhPxJj1PVjj/view?usp=sharing

I do know of some unknowns with the arrival time prediction graph and the CME cross-section. In the preliminary arrival time prediction graph the M0 line is likely higher than what I have in the graph. That would also mean that the Secondary Shock in the cross section is likely wider than what is currently shown compared to the Leading Shock.

The span of the decline between the Leading and Secondary Shock and its shape per CME is currently an unknown.

One question that would come up is why would there be a Leading and Secondary Shock? My answer would be that it is because of the internal structure of CMEs. This became the first basic sketch I made of how I see and understand the internal structure of some Coronal Mass Ejections, https://drive.google.com/file/d/19EWN0lc8leRp0gagOXxtg5Cbt18jFSP8/view?usp=sharing. For most CMEs I believe they have 3 layers and each layer is made of two halves. 

Given the distance between the M3 and M2 line in the arrival time forecast graph, there is an idea of how the internal structure of a CME is spaced apart. The number is close to sqrt(pi/2) or ~1.25. Say the Leading Shock has traveled 10Rsun. The position of the next internal layer would have traveled around 8Rsun.

There is a downside to my arrival time prediction method and it is that the CME must be visible throughout most of the coronagraph imagery. I don't think there will be a way to fix that, but as long as progress is made to help different fields of Coronal Mass Ejection research that is fine by me.

I have the imagery of 170 events currently to go through, so it should be a pretty good year. Updates will be made when available.

[Solarflaretracker200]

Holy crap man. That’s pretty cool. So you basically track CME’s from SOHO and all those type of stations? Cool! I tried doing that once but I gave up because CME’s happen suddenly and I don’t get on them most of the time. But yeah that’s pretty cool that you track them. 

[Sam Warfel]

Amazing work, the stuff about figuring out the interior structure of CMEs is very cool, I’ve never seen anything talking about that before. Keep up the good work!

Will this tool be ready to use to help predict the arrival time of any major CMEs we may get in this next year?

[Jesterface23]

The CView tool would be ready to help analyze upcoming CMEs, but I will need to continue using my old arrival time prediction graphs until I can go through my full list of CMEs with the tool.

[Sam Warfel]

10 minutes ago, Jesterface23 said:

The CView tool would be ready to help analyze upcoming CMEs, but I will need to continue using my old arrival time prediction graphs until I can go through my full list of CMEs with the tool.

I eagerly await more updates!

[Drax Spacex]

I didn't realize how capable Desmos is.  It's like a mini-Matlab.

From imagery "pixel speed," how do you determine the speed of the Earth-directed CME component?

[Jesterface23]

4 hours ago, Drax Spacex said:

From imagery "pixel speed," how do you determine the speed of the Earth-directed CME component?

The speed of the Earth-directed CME component would be derived from the estimated time of travel.

 

The below is how my arrival time prediction method works. Also if the process is done in reverse that is how the arrival time prediction graphs were created.

 

Launch: 2021/11/02 02:34Z

P1: ~06:40Z   - The CME reaches ~32Rsun in the northern part of the coronagraph imagery
P2: ~11:40Z   - The CME reaches ~32Rsun in the southern part of the coronagraph imagery

P1/P2 Difference: 5:00
P3: 09:10Z    - The midpoint time of P1 and P2

Launch/P3 Difference: 6:36

 

P1/P2 Difference is the x-axis value to use in the arrival time prediction graph.

P3 is the time between P1 and P2. It is what allows calculations to be made for the center of the coronagraph imagery.

In the coronagraph imagery one side was the Leading Shock and the other side was the Secondary Shock. We ended up being impacted by the Leading shock and that means the M2 line is used from the arrival time prediction graph.

The number obtained from the graph is ~6.3. 6.3 is then multiplied by the Launch/P3 Difference and the estimated travel time comes to 41.58 hours and an estimated arrival time at L1 of 2021/11/03 20:09Z.