Talk:Coronal mass ejection

Relationship to Cosmic Rays?
Under section "Impact on Earth", the last paragraph starts with "Humans at high altitudes, as in airplanes or space stations, risk exposure to relatively intense cosmic rays." Cosmic rays are largely from outside the solar system. So why does it mention cosmic rays here? There's one article online that claims that solar flares might reduce cosmic ray exposure of astronauts through a Forbush effect. (see http://science.nasa.gov/science-news/science-at-nasa/2005/07oct_afraid/). But otherwise the wiki article states no relationship between cosmic rays and CMEs. — Preceding unsigned comment added by 75.101.96.71 (talk) 02:00, 11 September 2014 (UTC)

New Image
I've reverted back to the old one, as it's much better and clearer to make out the CME's in.

Effect of CME?
This sentence moved from the article needs expert attention: The polarization of water molecules and the amount of deuterium within the atmosphere is dependent of the intesity (believe it or not).

Could it be saying that a CME affects Earth's upper atmosphere such that lighter hydrogen atoms are selectively lost leading to more deuterium remaining in water which in turn affects their average polarization? -Wikianon 09:56, 26 October 2006 (UTC)

Should a CME be defined as being observed by a coronagraph? If LASCO or STEREO is down, is there no CMEs? I think, "sometimes (or usually) observed by coronagraphs" should be a corrected definition of the first sentence USferdinand 02:10, 16 January 2007 (UTC)


 * I'll have a look at this page. I'm a solar physicist. Had fun creating the coronal loops page, so I'll see what I can do here -- iano (talk) 15:23, 16 June 2008 (UTC)

Lack of information
Where is size? Or temperature? Common folks would be interested in that sort of things.

Would be nice to mention actual biggest recorded CME with sources and parameters. —The preceding unsigned comment was added by 83.144.95.66 (talk) 11:55, 12 May 2007 (UTC).

Where did "The average mass is 1.6×10^12 kg" come from? According to one of the references (http://helios.gsfc.nasa.gov/cme.html), "[e]ach CME releases up to 100 billion kg". That would indicate a general upper bound of 10^11 kg. -- bcwhite (talk) 11:26, 4 January 2011 (UTC)

Stargate Atlantis
I believe that it was a solar flare that caused SG-1 to travel back in time to 1969, and John Sheppard approx. 40,000 years into the future,  not a coronal mass ejection as stated in the article. Also, previously not mentioned is the episode "2010" (where Colonel O'Neill sent a note back in time using a solar flare (from 2010) that warned the present day [read: 2000] SGC of the Aschen, and to stay away from them at all costs) [Disclaimer: I am a self-described Stargate nerd.] - AnubisAscended (talk) 02:46, 23 August 2008 (UTC)

You're right. In the SG-1 episodes 1969 and 2010, a solar flare allowed time travel into the past, and in the Atlantis episode: The Last Man Standing it allowed time travel to the future. While CMEs caused totally different problems. 24.33.243.152 (talk) 22:25, 27 September 2008 (UTC)

There is mention of a coronal mass ejection in the 3rd season of Stargate Atlantis ("Echoes", specifically) where the native marine life warns the Atlantis Expedition of an impending coronal mass ejection. AnubisAscended (talk) 03:24, 28 January 2009 (UTC)

What's the difference? Isn't a CME just a big solar flare? —Preceding unsigned comment added by 149.4.203.60 (talk) 18:17, 5 August 2010 (UTC)


 * Look at it this way, if the sun was a volcano, a solar flare would light up your house from the bright display and you could sweep the ash off your roof later. A CME is like when the volcano landed on your house, making it difficult to find your broom. Or if it was a BBQ, a solar flare is where everyone is coughing because there is too much smoke all around the yard coming from the BBQ, and a CME is where some twit managed to pour enough fuel into the BBQ for it to run to the bottom of the BBQ prior to full ignition, and the BBQ lands all around the yard, from where it produces some smoke naturally. Like that. Obviously, neither this article or the solar flare article explain the difference well enough if editors are asking these questions. Penyulap   talk 04:15, 30 December 2011 (UTC)

CME impact observed by Cluster
I added an external link. It looks like some other process than magnetic reconnection was involved. I added an inline citation at Cluster mission but alas this is not free to read (except abstract). I wonder if this should be mentioned in the CME impact section, or is it too early and speculative? Puzl bustr (talk) 16:39, 26 November 2009 (UTC)

Post-eruption arcade piccy
It is here. Note that on the TRACE pictures site it says: "The TRACE images may be used without restrictions in publications of any kind. We appreciate an acknowledgement indicating that the Transition Region and Coronal Explorer, TRACE, is a mission of the Stanford-Lockheed Institute for Space Research, and part of the NASA Small Explorer program.". Thus these pictures are usable by wikipedia. They also have a lovely picture of a coronal arcade here (the Bastille Day fireworks). Puzl bustr (talk) 21:48, 2 December 2009 (UTC)

August 2010 flare
I see somebody has added a section about the August 2010 'flare'. This is in fact a pretty minor thing, only magnitude C3.2, so the effects when it hits earth today will be also pretty minor. Perhaps some small aurora and associated propagation on the radio bands but most people will be unaware of it. Unfortunately the media has picked this up and blown it out of all proportion, and WP is not immune having linked this article from the main page. Flares are rated on a logarithmic scale much as earthquakes are. Only the higher M class and X class flares are likely to cause major disturbance and risk of damage to power networks etc. Since not one of the other countless flares of this magnitude has its own section I suggest the section is deleted - and we will know by the end of this week whether it has done anything to be put into the category of 'major solar flares'.... Dsergeant (talk) 06:06, 4 August 2010 (UTC)
 * The world is not going to end? Yet another disappointment.  Algr (talk)
 * The context you provide is much appreciated. I tried to piece together a picture last night by reading our articles and some news articles, but I was unable to get to the understanding which you provide. The CME article should explain these things better providing examples and tables. __meco (talk) 10:47, 4 August 2010 (UTC)
 * This section in the article really does need to be removed, as a blatant case of recentism. As folks have mentioned, this is a relatively minor event. Thanks to the anonymous editor below who provided links to much better examples of more intense events. Remember, just because the news outlets go bonkers, doesn't mean it is notable in an encyclopedic or historical sense. — Huntster (t @ c) 01:59, 5 August 2010 (UTC)
 * It's those goddamn Firstborn trying to kill us, I tell you. Half  Shadow  02:12, 5 August 2010 (UTC)
 * I don't know about any "Firstborn" nonsense, but I know the handiwork of wild sun monkeys when I see it. Throwing giant balls of plasma at Earth...they've got some nerve. In all seriousness, unless a good reason can be given for keeping this section, I'm going to remove it in a couple of days. — Huntster (t @ c) 02:17, 5 August 2010 (UTC)
 * I don't think removing this is the right thing to do. From what I can gather the sun was long overdue for sunspot activity, and with filaments coming loose the were half the size of the sun disk itself, this is spectacular, maybe only for the reason that this was the first time modern technology made it possible for all to take part in this. __meco (talk) 08:31, 5 August 2010 (UTC)
 * The Kp index didn't rise higher than 6, and the event was classified as a G2 (moderate) geomagnetic storm (see http://www.swpc.noaa.gov/rt_plots/kp_3d.html or http://www.swpc.noaa.gov/alerts/warnings_timeline.html). This event doesn't really seem noteworthy, except that it is one of the first of the new solar cycle. I'm for removal. For instance, the bastille day event which involved CMEs is much more relevant. Cochonfou (talk) 11:48, 5 August 2010 (UTC)
 * In fact it is not even the first in the new cycle as we had a very much bigger M8.3 one in February. It didn't get coverage because it wasn't earth pointing. The reasons for deletion remain. If we are going to do a detailed analysis of one particular flare there are hundreds of better examples. Dsergeant (talk) 12:55, 5 August 2010 (UTC)


 * Gents, I wrote most of the update for the August 2010 event, and I'll happily admit that I'm not a expert on the subject, as are some here. I was merely tasked at ITN with providing an update worthy of MP and I attempted to do that to the best of my ability. However, and surprising as it may sound, I have no strong opinions in this matter. If indeed this was a relatively minor event and consensus agrees it is not worthy of being represented here then by all means delete it at your leisure. However, I strongly suggest that you at least wait until the event is off MP so that readers can still be linked here. Once the event is off MP, then do what you will; I have no objections. Being that it took me bloody four hours to put it all together and add in the vid and pics and a considerable amount of lobbying to get it posted on MP (at the request of another editor), I feel inclined to keep it, but as I said before, I am not an expert and I will not stand in the way of consensus of those who are. Therefore if it should come to a straight vote for deletion I humbly Abstain. Although I would point out that because of this section the page view count increased between yesterday and today to 233,118 from a total of 6961 last month and a grand total of 72704 so far this year: (encyclopedic value is only relevant if people actively seek the information). Therefore you might all consider the exponential exposure Coronal Mass Ejection is getting from this before coming to a conclusive decision. Cheers gentlemen!  Cwill151 (talk) 23:40, 5 August 2010 (UTC)
 * I wouldn't want to dismiss the value of your work - we all know that editing wikipedia takes up time, and that effort should be recognized. But I really believe the article in its current state is giving the event an undue weight. More than 3/4 of the history section is taken by this relatively minor event ! However, deleting all the information contributed by the editors (which is still growing) might not be a good idea. Why not just split the event to its own article, and link it from here ? Cochonfou (talk) 07:47, 7 August 2010 (UTC)
 * I must say, I've had bad experiences with exactly this sort of situation before, where "zealous" editors have actively campaigned against "the destruction of 'their' articles with the addition of ITN garbage", but you haven't done that. You've been nothing but reasonable, sensible, and civil; and I appreciate and respect that. Thank you. As for giving the update it's own article, I had toyed with that idea as well, and it's not a bad one... but, as you say, given the event's minor status as it actually relates to the topic of CME, I'm not sure it would meet notability criteria for it's own article. You are also further correct, I was painfully aware when I wrote the update that it used almost as much space as the article itself, which is never good. However, I think there is a solution that could satisfy everyone involved... Why not follow the "lengthy comment" below and create a listing of major CME's in recent times, which would ostensibly include the august 2010 event, lord knows that the anon has already given us plenty of information to work with. That way CME can remain as a descriptive function about the concept itself and the listing created can function as a further study of the notable events that have been documented thus far. That way the current article will not be overshadowed by in-depth coverage of one event, and the 2010 update can remain intact simply on another page; a page which would meet notability criteria. As I said before, I'm not an expert, but I do consider myself at least a diligent editor and one with a desire to help where I can, and so I would be more than happy to help create and edit the listing if you wish. More information, and less, at the same time; now that's encyclopedic. Cheers! Cwill151 (talk) 17:46, 7 August 2010 (UTC)
 * Yes, if a good history of known large events can be written up, there's no real reason to exclude this one, though I think this event must be presented in context to the other, much more significant ones. — Huntster (t @ c) 00:20, 8 August 2010 (UTC)

Lengthy comment
(this is a lengthy comment ... and I'm not coming back ; therefore, I don't mind if the 'page keepers' delete it , or reduce it to a brief summary , if they like ; just consider what I have proposed , and do as you prefer).

submitted : 8pm 08/04/2010, by mmw220 by yahoo company .com (any account I may have had here under that user name is now inaccessible, as I don't recall my wiki password).

significant Historical events : solar disturbances

some events (like the August 2010 event) are unremarkable except for possibly allowing people to view the aurora at lower (populated) latitudes ; others had 'serious' consequences.

at least one of these, is already named and discussed in http://en.wikipedia.org/wiki/March_1989_geomagnetic_storm and http://en.wikipedia.org/wiki/Geomagnetic_storm (which indirectly refers to a storm of 1921 ...)

but there are some, such as the Jan 2005 flare , which produced particle 'radiation' travelling at half the speed of light, endangering astronauts circling the earth , that may also deserve mention.

People who keep this page updated should consider developing a 'major flares' or 'remarkable solar disturbances' page , or section within an existing page, to collect and explain (or link to existing pages that explain issues and effects of) the more significant events, and provide the perspective that an encyclopedic resource is specifically designed for. Some of these events are on 'their own' pages, and might better be consolidated as link#sub-head items on 1 page.

The problem is complicated by the interrelation of CME's solar flares, and geomagnetic storms , each of which has it's own separate page. An event may be interesting only in one of these contexts, or in some other way , but your readers won't get historical perspective on these physical processes unless notable events are collected together.

here are just a few dates from the Washington Post , hardly the most complete source for this branch of science , and wikipedia itself (organized going backwards) :

2006, 2005, 2003, 2000,, 1989,, 1960,, 1921,, 1859,, (more at recent dates because better scientific understanding and measurement gear was available ?)

http://www.washingtonpost.com/wp-dyn/content/article/2007/04/07/AR2007040700916.html

Intense Solar Flare Worries Scientists ; Sunday, April 8, 2007 (refers to an event in Dec, 2006)

The Dec. 6 solar flare spawned an intense burst of radio wave radiation, including some at the same frequencies used by GPS hardware ... "This radio event was 10 to 20 times bigger than anything we had measured before, or thought would reach Earth from the sun," said William Murtagh of the NOAA ...

http://www.washingtonpost.com/wp-dyn/content/article/2005/05/29/AR2005052900829.html

Science Notebook ... Solar Flare Confounds Scientists ; Monday, May 30, 2005

on Jan. 20, the most intense burst of solar radiation in 50 years sped to Earth after an enormous solar flare. The radiation reached Earth in 15 minutes -- much faster than the two or more hours normally required, researchers said last week.

[ that's half the speed of light, or 360 million mph , not the 'usual' ~1 million mph ... for particle radiation ! ]

(OK, but that means there was an even larger one in 1955 - or was that 1960 ... see below)

http://www.washingtonpost.com/wp-dyn/articles/A37614-2004Jul8.html

Storms Race From Sun To Brink Of System (refers to the 'Halloween storms' of Oct 2003) ; Spacecraft Report Effects to Scientists ; Friday, July 9, 2004

Eight months after storms exploded from the sun's surface at 5 million mph, the spectacular blast wave is still traveling to the edge of the solar system, scientists said yesterday.

The Halloween storms began Oct. 22 when solar flares began exploding from sunspots, emitting enormous surges of energy and radiation as billions of tons of charged particles deluged the solar system.

On Oct. 28, a solar flare triggered two "coronal mass ejections" that headed for Earth at 5 million mph.

"These were enormous explosions," said Eric R. Christian, chief of NASA's solar physics division, but they were topped by a Nov. 4 surge, the most intense solar flare ever recorded. "In a short time, all these explosions combined to form an amazing blast wave."

Reference article :

http://www.washingtonpost.com/wp-dyn/articles/A11417-2003Oct24.html

Solar Storm Could Hinder Satellite, Cell Phone Signals ; Friday, October 24, 2003

The disturbance was expected to produce a geomagnetic storm rated G3. A G5 storm is the strongest.

following item occurred (June 7, 2000) nearly at the same time (July 14, 2000) as http://en.wikipedia.org/wiki/Bastille_Day_event

the biggest solar radiation event since 1989.[3] The proton event was four times more intense than any previously recorded since the launches of SOHO in 1995 and ACE in 1997.[1] The flare was followed by a full-halo coronal mass ejection.[1]

just a month earlier, we have ... http://www.washingtonpost.com/wp-srv/aponline/20000607/aponline130228_000.htm

Major Solar Storm Detected ; Wednesday, June 7, 2000; 1:02 p.m. EDT

In 1989, a severe solar storm knocked out power stations serving Canada and the northeastern states, as well as an electrical transformer in New Jersey. Since then, power grid and satellite operators have taken steps to protect their systems.

This item is already at wikipedia ... as mentioned , but not well-linked or discussed.

wikipedia also refers elsewhere to the 'grand-daddy' event in modern history which seems to be ...

http://en.wikipedia.org/wiki/Solar_storm_of_1859 The most powerful flare of the last 500 years was the first flare to be observed, and occurred in September 1859: it was ... from August 28 until September 2, 1859 ... numerous sunspots

less severe storms have occurred in 1921 and 1960, when widespread radio disruption was reported

(those 2 storms are not quantified or ranked for comparison with other events ... Actually most of the events need to have their features quantified)

I'm sure someone who studies these physical processes knows of more 'interesting' events in the last 150 years , or in earlier times, before the science was developed. —Preceding unsigned comment added by 71.168.0.107 (talk) 00:15, 5 August 2010 (UTC)


 * I commend you for providing this concise and orderly presentation which will surely make it into one or more of the articles you mention, including the present one. __meco (talk) 19:02, 5 August 2010 (UTC)

Time zones
I changed the "(European time)" after the UTC listings to "(approximately the same as Greenwich Mean Time)". This is more accurate, especially since Anglophone nations in Europe consider "European time" to be an hour or two ahead of UTC/GMT. Brammers (talk/c) 11:48, 4 August 2010 (UTC)


 * There are very few "Anglophone nations" in Europe. Perhaps you would like to name them.  Careful with this one.  —Preceding unsigned comment added by 69.171.176.149 (talk) 05:47, 13 August 2010 (UTC)

Watching August 2010 CME?
If the CME is happening between wednesday and thursday why does it say we should be watching for the auroras between tuesday and wednesday? —Preceding unsigned comment added by 149.4.203.60 (talk) 19:07, 4 August 2010 (UTC)

Frequency of ejections
From the introduction: "Near solar maxima the Sun produces about 3 CMEs every day, whereas near solar minima there is about 1 CME every 5 days." (Supported by NASA reference)

In physical properties: "The frequency of ejections depends on the phase of the solar cycle: from about one every other day near the solar minimum to 5–6 per day near the solar maximum. These values are also lower limits because ejections propagating away from Earth (backside CMEs) can usually not be detected by coronagraphs." Unsupported statement.

The numbers do not match... I've inserted a Citation needed, but someone should clean this up. — Preceding unsigned comment added by Marius EE (talk • contribs) 19:05, 25 November 2011 (UTC)

I found numbers matching the NASA numbers in my astrophysics book: I updated the Physical Properties section with new numbers and citation.Marius EE (talk) 23:06, 25 November 2011 (UTC)

Readers of this article want to know...
...would Wikipedia be destroyed? Should we keep a copy of Wikipedia deep underground or some such thing? Chrisrus (talk) 04:35, 18 April 2014 (UTC)
 * Readers want to know - are you medicated? — Preceding unsigned comment added by 50.111.46.194 (talk) 22:09, 4 November 2016 (UTC)
 * haha!--Tallard (talk) 20:13, 25 July 2018 (UTC)

Impact on Earth
The last sentence of this section needs clarification:
 * "The energy absorbed by astronauts is not reduced by a typical spacecraft shield design and, if any protection is provided, it would result from changes in the microscopic inhomogeneity of the energy absorption events."

1) What would "result", the protection? That doesn't make sense.

2) This says the energy absorbed is not reduced, then says something about changes in absorption.

Obviously it's a poorly constructed sentence, but I don't understand the intended meaning enough to fix it. Autumn Wind (talk) 17:38, 22 June 2016 (UTC)

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An "in popular media" section
It would be nice to discuss any films/tv/books which mention, or imply, a CME event or fictional catastrophe, and debunk whatever falsities and confirm any correct opinions of said event/catastrophe. For example, some people are saying that a CME is the unnamed causal catastrophe agent in the film How it ends. I know nothing of this topic, but would be interesting to know. --Tallard (talk) 20:22, 25 July 2018 (UTC)

Some promo stuff about "eruptions"
Recently, reverted my recent removal of material concerning coronal magnetic structures:. I don't have much emotion about this, but, to me, this material looks like simple promo. I say this because some of it is obvious, yes, "Coronal mass ejections are associated with enormous changes and disturbances in the coronal magnetic field". That is, after all, mainstream thinking, not new. Then, the material introduces a new and unconventional terminology: "coronal mass eruptions", which I don't think is much to brag about. And, finally, all that is cited is a bunch of recent conference abstracts. These are not typical reviewed nor typically even cited. Anyway, with substantial revision, maybe some of this could reasonably be in this article. I suppose. But I'm not going to revise it. I also won't remove it if JRPG wants it (or if someone else does). Too many things to do. Attic Salt (talk) 14:40, 18 August 2018 (UTC)

Description section needs more detail
The EM is mentioned, but not described. Please flesh this out a bit. HammerFilmFan (talk) 06:02, 20 January 2020 (UTC)

Proposal to change Solar particle event to a redirect to this article
The article Solar particle event confusingly refers instead to "solar proton event" (SPE) in the text. Although there are differences in terminology, the SPE article seems to duplicate the CME one. The Carrington event is described as a CME, but this article descibes it as an SPE. As the SPE article largely duplicates this one and it is almost wholly unreferenced, I suggest changing Solar particle event to a redirect to this article.

Multiradionuclide evidence for an extreme solar proton event around 2,610 B.P. is of interest both as a more ancient record of a SPE, and as referring to the 774 event as an SPE. Both appear to be ancient CMEs which are not covered in this article. This article states "We find evidence that a mass ejection event is a necessary condition for the occurrence of a prompt proton event." Is anyone expert enough to sort out the confusion in the terminology? Dudley Miles (talk) 19:24, 3 February 2020 (UTC)
 * My understanding is that these two concepts are different. The main feature of an SPE is the acceleration of the protons to high speeds. Flares can generate SPEs and some CMEs can also do so. SPEs can reach the earth in tens of minutes, whereas CMEs that don't generate SPEs usually take a few days to reach earth. Non-SPE CME protons deform the magnetosphere but do not reach the atmosphere. SPE protons reach the atmosphere, increasing its ionization. -- 19:45, 3 February 2020 (UTC)


 * Thanks. That is very helpful.
 * Do you think that the two articles should be kept separate?
 * Are 'solar particle event', 'solar proton event' and 'prompt proton event' symonyms? Dudley Miles (talk) 20:29, 3 February 2020 (UTC)
 * I think a merge is a possibility. But I am not an expert either and would want the opinion of more knowledgable editors on that. As I understand it, in a 'solar particle event' most of the particles are protons, so 'solar proton event' is used as a synonym. I've seen the term 'prompt solar proton event' and could believe that it was contracted to 'prompt proton event', but could not say for sure. -- 21:22, 3 February 2020 (UTC)

CMEs and SPEs are different phenomena, though related. As noted above, flares (these are associated with CMEs) are a possible source of SPEs, but SPEs can also be generated by a CME as it traverses interplanetary space -- the shock front of the CME accelerates protons and can, thus, be a substantial source of SPEs. Thanks, Attic Salt (talk) 21:38, 3 February 2020 (UTC)


 * Thanks . Do you think that they are so closely related that a single article makes sense or it is helpful to have separate articles? Dudley Miles (talk) 22:11, 3 February 2020 (UTC)
 * They deserve to be seperate articles. Attic Salt (talk) 22:25, 3 February 2020 (UTC)
 * Would it be correct to say that SPEs are all produced by CMEs, either ones produced by a CME as it traverses interplanetary space, or by a flare in the solar atmosphere produced by a CME? Dudley Miles (talk) 22:54, 3 February 2020 (UTC)
 * I don’t know about that. I have some, but limited, knowledge on this subject. Not enough to answer that specific question. Attic Salt (talk) 23:00, 3 February 2020 (UTC)
 * Why do they deserve to be separate articles? Geoffrey.landis (talk) 14:10, 22 March 2022 (UTC)
 * They deserve to have different articles because they are simply different phenomena. An SPE is an acceleration of solar particles to relativistic speeds, whereas a CME is an acceleration of bulk plasma and magnetic field. The two can and often do occur in tandem, but they aren't the same phenomena as others have already mentioned above. Additionally, they affect Earth in different ways. Earth-directed SPEs can arrive at Earth in tens of minutes, unlike CMEs which usually take days. SPEs also do not distort the interplanetary magnetic field and thus have no geomagnetic effects, unlike CMEs which may cause geomagnetic storms. The NOAA SWPC even define, analyze, and categorize them differently. For these reasons, it is quite clear (to me at least) that the two should be differentiated with separate articles.
 * Also, keep in mind that OP's quote and the evidence mentioned therein is from 1978. For a more recent example which demonstrates the difference between the two, check out the events during the Bastille Day solar storm. If I remember correctly, all of the academic papers that I have read on that event treat the SPE and CME separately which is reflected in Bastille Day solar storm. In particular, note that the initial SPE arrives at Earth one day prior to the CME. CoronalMassAffection (talk) 22:00, 22 March 2022 (UTC)


 * Neither of the sources you cite even uses the term "Solar Particle Event". Geoffrey.landis (talk) 02:02, 23 March 2022 (UTC)
 * The term solar radiation storm (used by the NOAA) and solar (energetic) particle event refer to the same phenomenon. Sorry, I should have made this more clear. CoronalMassAffection (talk) 03:16, 23 March 2022 (UTC)
 * The term solar radiation storm (used by the NOAA) and solar (energetic) particle event refer to the same phenomenon. Sorry, I should have made this more clear. CoronalMassAffection (talk) 03:16, 23 March 2022 (UTC)

White-light coronagraph media?
Does anyone think this article could benefit from the addition of an image/GIF/video of an erupting CME seen with a white-light coronagraph? The article itself even mentions that "[t]hey are usually observed with a white-light coronagraph." It would also give an opportunity to show the structure of a CME (i.e., the core, cavity, and leading-edge). There are many good examples in the available LASCO data such as the event in the two example GIFs I have provided on the right. (The rightmost image is a running-difference version of the leftmost.) CoronalMassAffection (talk) 05:23, 27 August 2021 (UTC)


 * Yes, definitely! Geoffrey.landis (talk) 02:39, 23 March 2022 (UTC)
 * ✔️. CoronalMassAffection (talk) 00:16, 6 April 2022 (UTC)

Merger proposal
I am proposing that the article coronal cloud by merged with coronal mass ejection. As the former article puts it, "[a] coronal cloud is the cloud of hot plasma gas surrounding a coronal mass ejection" and, in my opinion, an entire article does not need to be dedicated to a single component of a CME.

This is also ignoring the fact that I have never heard the term coronal cloud being used in that sense. And I don't believe I am alone in that. In the single cited source that contains the phrase "coronal cloud", it is in reference to a type of prominence... a type of prominence which is shown to appear 1 to 2 days after a CME. In addition to this, the first section makes absolutely no sense and is in no way supported by the cited sources. The rest of the article then goes on to provide identical information to that provided here and in list of solar storms. CoronalMassAffection (talk) 08:37, 28 August 2021 (UTC)
 * Support, provided that is willing to undertaker the work of carrying through the merger. Coronal mass ejection gets 22,600 hits on Google Scholar. None of the references for Coronal cloud have the words in their title and it only 136 hits on Google Scholar. This is possibly enough for a section in the Coronal mass ejection article, but not for a separate article. Dudley Miles (talk) 09:34, 28 August 2021 (UTC)
 * As an additional note, Coronal cloud doesn't actually have any (correct/supported by sources) information that isn't already present in Coronal mass ejection and List of solar storms (and articles linked therein) meaning that this merger won't require that any changes be made to Coronal mass ejection. Additionally, because Coronal cloud's title is referring to coronal cloud prominences (cf. channel prominences), it would make more sense to have Coronal cloud redirect to Solar prominence rather than to the actual destination of the merger. (And to clarify, the reason why I proposed a merger with the CME article rather than the prominence article was based on the CME-related content of Coronal cloud, not its prominence-related title.) CoronalMassAffection (talk) 01:33, 1 September 2021 (UTC)


 * If the coronal cloud article does not have any information to merge, then you are not proposing a merger. I suggest that you close this discussion and be wp:bold. Change coronal cloud to a redirect, adding a note on the talk page explaining the reasons. Dudley Miles (talk) 08:53, 1 September 2021 (UTC)
 * Thanks for the help! CoronalMassAffection (talk) 10:34, 1 September 2021 (UTC)

Further reading dead link
This link isn't working:

Morring, Frank, Jr. (14 January 2013). "Major Solar Event Could Devastate Power Grid". Aviation Week & Space Technology. 2605:A601:A6D6:1:78C1:43A1:1020:311D (talk) 12:54, 17 April 2022 (UTC)
 * I have deleted it. Dudley Miles (talk) 21:18, 17 April 2022 (UTC)

A Commons file used on this page or its Wikidata item has been nominated for deletion
The following Wikimedia Commons file used on this page or its Wikidata item has been nominated for deletion: Participate in the deletion discussion at the. —Community Tech bot (talk) 12:07, 22 April 2022 (UTC)
 * Large coronal mass ejection on 2000-02-26 from SOHO LASCO C2 coronagraph.jpg

How the coronal mass ejection happens?
HOW THE CORONAL MASS EJECTION HAPPENS? PLEASE EXPLAIN Ramkumar swarnkar soni (talk) 05:45, 17 March 2023 (UTC)

Rip the Sun apart
In Coronal mass ejection, it is stated that, without CMEs removing helicity from the corona, "the twists would renew themselves continuously each solar cycle and eventually rip the Sun apart." I think the weight given to this info is WP:UNDUE if it really just amounts to speculation and is not supported by any other source. Nonetheless, I have refrained from outright removing it since the one source provided is from Lucie Green, an WP:RS. I would appreciate any insight here. CoronalMassAffection (talk) 22:09, 5 April 2023 (UTC)
 * I am not sure whether there is any guidance on this point, but reliable sources often disagree, and we should reflect the consensus. If other sources dispute Green's vew, then we could give each side (naming the authors inline), but no one even comments I would delete. Giving her view without any caveat would be misleading. Dudley Miles (talk) 22:51, 5 April 2023 (UTC)

Article layout
At present, the article feels all over the place, and I think a more coherent layout is warranted given its status as a vital astronomy article. Something like the following seems more appropriate: I have intentionally left out an "Associated phenomena" section, as I believe it would be best to integrate this information into the other sections (e.g., flares, eruptive prominences, and sigmoids in the "Origin and initiation" section; EUV waves, Forbush decrease, and radio emission in the "Propagation" section). CoronalMassAffection (talk) 21:06, 7 April 2023 (UTC)
 * 1) Lead
 * 2) Physical description
 * 3) Origin and initiation (i.e., cause, trigger mechanisms, frequency/solar cycle, composition)
 * 4) Propagation (i.e., post-eruption dynamics, acceleration, propagation through the corona and interplanetary space)
 * 5) Impact on Earth
 * 6) History
 * 7) Stellar CMEs
 * 8) See also, References, etc.