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Hhudson — Tue, 07 Jul 2026 10:51:49 GMT

Added No. 530

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 Welcome to the [[SolarNuggets]] collection, which extends the series of [[RHESSI]] Nuggets.  The following is a time-ordered list of the latest Nuggets added to the HelioWiki.  An [[:Category:Nugget|alphabetical list of the SolarNuggets]] is also available as well as [[:Category:RHESSI Nugget List|yearly lists]]. One can search on author, topic, IAU flare identifier, etc.). We welcome volunteer authors - please see our page of [[Help:For_Authors| help for authors]] or just send an email to the Curator at (hugh.hudson@glasgow.ac.uk).
 {{Nugget Badge
 |title = Particle Pressure and CMEs

Filament Eruptions as seen in the Sun-as-a-star H-alpha Spectrum

Hhudson — Sun, 05 Jul 2026 14:58:27 GMT

No. 530 initial upload

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Hhudson — Sun, 05 Jul 2026 14:56:33 GMT

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Hhudson — Sun, 05 Jul 2026 14:56:14 GMT

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Filament Eruptions as seen in the Sun-as-a-star H-alpha Spectrum

Hhudson — Sun, 05 Jul 2026 09:03:42 GMT

← Older revision		Revision as of 09:03, 5 July 2026
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	=== On-disk vs. Limb: the line wings ===		=== On-disk vs. Limb: the line wings ===

			The primary observational difference between on-disk and limb
			eruptions arises from the contrasting Hα appearance of filaments
			against their backgrounds. On the disk, filaments appear as dark
			absorption structures; when they erupt, cool dense material moving
			toward the observer blocks background radiation, producing blue-wing
			absorption in the integrated spectrum (see the magenta ellipse in
			Figure 1. b1). At the limb, prominences appear as bright emission
			structures against the dark background; erupting material produces
			blue-wing or red-wing emission signals (see the yellow ellipse in
			Figure 1. b2). Thus, the presence of emission in the far Hα wings
			is a strong indicator that the eruption occurred at the limb;
			otherwise, it is more likely an on-disk event.

			[[File:530f1.png\|center\|thumb\|600px\|caption\|Figure 1: <i>
			Hα imaging observations (a1a3) and corresponding Sun-as-a-star
			Hα dynamic
			spectra (b1b3) for three filament/prominence eruption events: an
			on-disk active-region eruption, a frontside limb active-region eruption,
			and a farside limb active-region eruption.
			</i>]]

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Hhudson — Sun, 05 Jul 2026 08:54:10 GMT

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Filament Eruptions as seen in the Sun-as-a-star H-alpha Spectrum

Hhudson — Sun, 05 Jul 2026 08:49:17 GMT

Created page with "{{Infobox Nugget |name = Nugget |title = Filament Eruptions as seen in the Sun-as-a-star H-alpha Spectrum |number = 530 |first_author = Junyi ZHANG |second_author = Yijun HOU |publish_date = July 6, 2026 |next_nugget = TBD |previous_nugget = {{#ask: Category:Nugget RHESSI Nugget Index::529}} }} == Introduction == Solar filament/prominence eruptions are among the most energetic phenomena in the solar atmosphere and are major drivers of [space weather]. The..."

New page

{{Infobox Nugget |name = Nugget
|title = Filament Eruptions as seen in the Sun-as-a-star H-alpha Spectrum
|number = 530
|first_author = Junyi ZHANG
|second_author = Yijun HOU
|publish_date = July 6, 2026
|next_nugget = TBD
|previous_nugget = {{#ask: [[Category:Nugget]] [[RHESSI Nugget Index::529]]}}
}}

== Introduction ==

Solar filament/prominence eruptions are among the most energetic
phenomena in the solar atmosphere and are major drivers of
[space weather].
Their geoeffectiveness depends partly on where they occur
on the Sun.
For stars beyond the Sun, however, we cannot obtain spatially resolved
images - they are observed as unresolved points.
When an eruption
happens in a localized region of a stellar atmosphere, can we infer
its approximate source location (near disk center or limb, front
side or far side, active region or quiet Sun) from subtle changes
in the star's integrated spectrum?

The answer is Yes.
We show (Ref. [1]) that filaments/prominences at
different locations display distinct radiative and dynamical
signatures during eruption, leaving identifiable imprints in the
integrated spectrum.
Using high-resolution full-disk Hα spectroscopic
data from the Chinese Hα Solar Explorer
([CHASE])
we have obtained clear spectral
fingerprints for each source-location category.

== Signatures ==

=== On-disk vs. Limb: the line wings ===

SolarNuggets

Hhudson — Fri, 26 Jun 2026 10:10:37 GMT

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	{{Nugget Badge		{{Nugget Badge
	\|title = White-Light and Lyman-alpha Emissions in Solar Flares: Timing, Timescale, Energy, and ~~Scaling~~		\|title = Particle Pressure and CMEs
			\|number = 529
			\|first_author = Hugh HUDSON
			\|second_author = and Ed CLIVER
			\|\|publish_date = 22 June 2026
			\|description = High-energy particles can exert substantial pressure and affect eruption dynamics
			\|image=Icon529.png}}

			{{Nugget Badge
			\|title = White-Light and Lyman-alpha Emissions in Solar Flares: Timing, Timescale, Energy, and Scaling‎‎
	\|number = 528		\|number = 528
	\|first_author = Dechao SONG ~~et al.~~		\|first_author = Dechao SONG
	\|\|publish_date = 8 June 2026		\|\|publish_date = 8 June 2026
	\|description = ~~First large sample~~ of white-light ~~and~~ Lyman-alpha ~~flare observations~~		\|description = A new catalog of white-light flares including novel Lyman-alpha data
	\|image=Icon528.png}}		\|image=Icon528.png}}

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Hhudson — Wed, 24 Jun 2026 14:10:35 GMT

Hhudson uploaded File:Icon529.png

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Particle Pressure and CMEs

Hhudson — Wed, 24 Jun 2026 10:13:22 GMT

CME dynamics

← Older revision		Revision as of 10:13, 24 June 2026
(4 intermediate revisions by the same user not shown)
Line 20:		Line 20:
	[https://news.uchicago.edu/explainer/what-are-cosmic-rays cosmic rays],		[https://news.uchicago.edu/explainer/what-are-cosmic-rays cosmic rays],
	even out to GeV energies.		even out to GeV energies.
	We cannot make <i>in situ</i> observations ~~anywhere close~~ to the Sun, and		We cannot make <i>in situ</i> observations closer than about 10 solar radii to the Sun, and
	the propagation of these "solar cosmic rays" throughout the		the propagation of these "solar cosmic rays" throughout the
	[https://en.wikipedia.org/wiki/Heliosphere heliosphere]		[https://en.wikipedia.org/wiki/Heliosphere heliosphere]
Line 27:		Line 27:
	mechanisms deriving energy from		mechanisms deriving energy from
	[https://spaceplace.nasa.gov/sun-corona/en/ coronal magnetic fields].		[https://spaceplace.nasa.gov/sun-corona/en/ coronal magnetic fields].
	~~Therefore SEPs are probably~~ present in the low corona at times.		Most of the magnetic energy is in the low corona, so accelerated particles must be present in the low corona at times.
	This Nugget discusses ~~one potential consequence of SEPs near~~ the ~~Sun~~.		This Nugget discusses the pressure exerted by high-energy particles low in the corona, which can rival
			the magnetic pressure.

	== The physics and the numbers ==		== The physics and the numbers ==
Line 38:		Line 39:
	of the plasma, and its effect is to expand the magnetic field in the		of the plasma, and its effect is to expand the magnetic field in the
	perpendicular direction.		perpendicular direction.
	From ~~SEPs~~ observations, we can roughly ~~describe~~ its significance		From SEP event observations, we can roughly quantify its significance relative to
	~~in a quantitative manner~~.		the magnetic pressure.
	A major CME may have a total energy of 10<sup>32</sup> erg, and we could		A major CME may have a total energy of 10<sup>32</sup> erg, and we could conservatively
	~~consider a~~ total ~~SEP~~ energy of 10<sup>30</sup> erg ~~(Ref. [1])~~.		take 1% as the particle fraction of the total energy (Ref. [1]).
			This is then 10<sup>30</sup> erg in particle energy.
	In the volume of a shell at 1 R<sub>☉</sub>, 0.1 R<sub>☉</sub>		In the volume of a shell at 1 R<sub>☉</sub>, 0.1 R<sub>☉</sub>
	thick and 1 sr in diameter, the particle energy density would correspond		thick and 1 sr in diameter, the particle energy density would correspond
Line 47:		Line 49:
	component in a closed field structure.		component in a closed field structure.
	Note that particle pressure applied to a closed magnetic field would be		Note that particle pressure applied to a closed magnetic field would be
	<i>outward</i>, ~~rather than~~ the <i>inward</i> force of magnetic tension.		<i>outward</i>, in opposition to the <i>inward</i> force of magnetic tension.

	== CME dynamics ==		== CME dynamics ==
Line 59:		Line 61:
	strongly suggests that a global shock wave could penetrate closed fields,		strongly suggests that a global shock wave could penetrate closed fields,
	as in a coronal		as in a coronal
	[helmet streamer]		[https://en.wikipedia.org/wiki/Helmet_streamer helmet streamer]
	and accelerate particles there.		and accelerate particles there.
	This has been borne out by modeling (e.g., Ref. [3]).		This has been borne out by modeling (e.g., Ref. [3]).
Line 75:		Line 77:
	== Conclusion ==		== Conclusion ==

	Non-thermal particle pressure typically has not ~~often~~ been considered in		Non-thermal particle pressure typically has not been considered in
	modeling CME initiation or propagation in the low corona.		modeling CME initiation or propagation in the low corona.
	With or without shock waves, the mechanism seems plausible: an ~~impulsive~~		With or without shock waves, the mechanism seems plausible: an electrodynamic process
	~~flare~~ accelerates particles, which pressurize the accessible field volume.		accelerates particles, which pressurize the accessible field volume.
	This drives expansion and creates or augments a CME and its interplanetary		This drives expansion and creates or augments a CME and its interplanetary
	aftermath; some of the energy added to expand the field can then return		aftermath; some of the energy added to expand the field can then return
Line 84:		Line 86:
	[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]		[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]
	process.		process.

	The important message here is that non-thermal particle pressure can have a		The important message here is that non-thermal particle pressure can have a
	powerful effect on magnetic structures in the solar corona in general.		powerful effect on magnetic structures in the solar corona in general.
	MHD simulations ~~in general~~ cannot paint a complete picture of coronal		MHD simulations intrinsically cannot paint a complete picture of coronal
	dynamics ~~without recognizing~~ this ~~elementary consideration.~~		dynamics because they do not include this basic physics.
	~~The dramatic discovery soft X-ray detection of dimming at the very~~
	~~bottom of the corona (e.g., Ref. [3]) should have sent this clear message~~
	~~already~~.

	== References ==		== References ==
Line 97:		Line 95:
	[1] [https://ui.adsabs.harvard.edu/abs/2005ESASP.592...67M/abstract "How Efficient are Coronal Mass Ejections at Accelerating Solar Energetic Particles?"]		[1] [https://ui.adsabs.harvard.edu/abs/2005ESASP.592...67M/abstract "How Efficient are Coronal Mass Ejections at Accelerating Solar Energetic Particles?"]

	[1] [https://ui.adsabs.harvard.edu/abs/1997SoPh..175..601D/abstract "EIT and LASCO Observations of the Initiation of a Coronal Mass Ejection"]		[2] [https://ui.adsabs.harvard.edu/abs/1997SoPh..175..601D/abstract "EIT and LASCO Observations of the Initiation of a Coronal Mass Ejection"]

	[3] [https://ui.adsabs.harvard.edu/abs/2017ApJ...851...38K "The Acceleration of High-energy Protons at Coronal Shocks: The Effect of Large-scale Streamer-like Magnetic Field Structures"]		[3] [https://ui.adsabs.harvard.edu/abs/2017ApJ...851...38K "The Acceleration of High-energy Protons at Coronal Shocks: The Effect of Large-scale Streamer-like Magnetic Field Structures"]

Particle Pressure and CMEs

Hhudson — Tue, 23 Jun 2026 12:54:41 GMT

No. 529 initial

New page

{{Infobox Nugget |name = Nugget
|title = Particle Pressure and CMEs
|number = 529
|first_author = Hugh HUDSON
|second_author = Ed CLIVER
|publish_date = June 22, 2026
|next_nugget = TBD
|previous_nugget = {{#ask: [[Category:Nugget]] [[RHESSI Nugget Index::528]]}}
}}

== Introduction ==

We know about solar energetic particles
[https://en.wikipedia.org/wiki/Solar_energetic_particles (SEPS)]
from many observations from instruments on space probes, and also from
ground-based observations such as those of
[https://neutronm.bartol.udel.edu/ neutron monitors].
SEP events occur only intermittently, often following powerful flares, and
when they do occur the particle fluxes far exceed those of the
[https://news.uchicago.edu/explainer/what-are-cosmic-rays cosmic rays],
even out to GeV energies.
We cannot make in situ observations anywhere close to the Sun, and
the propagation of these "solar cosmic rays" throughout the
[https://en.wikipedia.org/wiki/Heliosphere heliosphere]
remains somewhat mysterious.
But we can tell that the highest-energy particles come from acceleration
mechanisms deriving energy from
[https://spaceplace.nasa.gov/sun-corona/en/ coronal magnetic fields].
Therefore SEPs are probably present in the low corona at times.
This Nugget discusses one potential consequence of SEPs near the Sun.

== The physics and the numbers ==

The pressure exerted by high-energy particles basically reflects the
[https://en.wikipedia.org/wiki/Lorentz_force Lorentz force],
and so it is anisotropic.
This distinguishes it from the gas pressure exerted by the thermal core
of the plasma, and its effect is to expand the magnetic field in the
perpendicular direction.
From SEPs observations, we can roughly describe its significance
in a quantitative manner.
A major CME may have a total energy of 1032 erg, and we could
consider a total SEP energy of 1030 erg (Ref. [1]).
In the volume of a shell at 1 R☉, 0.1 R☉
thick and 1 sr in diameter, the particle energy density would correspond
to a magnetic field of 1 G, and is very likely the dominant pressure
component in a closed field structure.
Note that particle pressure applied to a closed magnetic field would be
outward, rather than the inward force of magnetic tension.

== CME dynamics ==

Flare-associated CMEs can originate impulsively, in the low corona
(Ref. [2]), in which case there is a dramatic and very sudden dimming.
Other CMEs may arise from streamer expansion or filament eruption,
as shown in Figure 1.
The right panel, originally published by
[https://en.wikipedia.org/wiki/Paul_Wild_(Australian_scientist) Paul Wild],
strongly suggests that a global shock wave could penetrate closed fields,
as in a coronal
[helmet streamer]
and accelerate particles there.
This has been borne out by modeling (e.g., Ref. [3]).

[[File:529f1.png|center|thumb|600px|caption|Figure 1: 
Sketches showing global waves emitted from the low corona:
[https://www.astro.gla.ac.uk/cartoons/Vainio-Khan_2004ApJ...600..451V_CME.html left],
showing the flank of a wave moving laterally, but somehow not entering
closed-field regions; and
[https://www.astro.gla.ac.uk/cartoons/Wild-1969_1969PASAu...1..181W_PHY.html right],
remedying that omission.
]]

== Conclusion ==

Non-thermal particle pressure typically has not often been considered in
modeling CME initiation or propagation in the low corona.
With or without shock waves, the mechanism seems plausible: an impulsive
flare accelerates particles, which pressurize the accessible field volume.
This drives expansion and creates or augments a CME and its interplanetary
aftermath; some of the energy added to expand the field can then return
in the normal
[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]
process.

The important message here is that non-thermal particle pressure can have a
powerful effect on magnetic structures in the solar corona in general.
MHD simulations in general cannot paint a complete picture of coronal
dynamics without recognizing this elementary consideration.
The dramatic discovery soft X-ray detection of dimming at the very
bottom of the corona (e.g., Ref. [3]) should have sent this clear message
already.

== References ==

[1] [https://ui.adsabs.harvard.edu/abs/2005ESASP.592...67M/abstract "How Efficient are Coronal Mass Ejections at Accelerating Solar Energetic Particles?"]

[1] [https://ui.adsabs.harvard.edu/abs/1997SoPh..175..601D/abstract "EIT and LASCO Observations of the Initiation of a Coronal Mass Ejection"]

[3] [https://ui.adsabs.harvard.edu/abs/2017ApJ...851...38K "The Acceleration of High-energy Protons at Coronal Shocks: The Effect of Large-scale Streamer-like Magnetic Field Structures"]

Streamer Blow-out CMEs and Particle Pressure

Hhudson — Tue, 23 Jun 2026 09:30:15 GMT

Solar radiation belts

← Older revision		Revision as of 09:30, 23 June 2026
(4 intermediate revisions by the same user not shown)
Line 26:		Line 26:
	But we can tell that the highest-energy particles come from acceleration		But we can tell that the highest-energy particles come from acceleration
	mechanisms deriving energy from		mechanisms deriving energy from
	[https://spaceplace.nasa.gov/sun-corona/en/ ~~§coronal~~ magnetic fields].		[https://spaceplace.nasa.gov/sun-corona/en/ coronal magnetic fields].
	Therefore SEPs are probably present in the low corona at times.		Therefore SEPs are probably present in the low corona at times.
	This Nugget discusses one potential consequence of SEPs near the Sun.		This Nugget discusses one potential consequence of SEPs near the Sun.
Line 38:		Line 38:
	that allow the		that allow the
	[https://physics.uiowa.edu/about/james-van-allen Van Allen]		[https://physics.uiowa.edu/about/james-van-allen Van Allen]
	belts to exist.		belts to exist (see also [https://heliowiki.smce.nasa.gov/wiki/index.php/Solar_radiation_belts%3F Nugget No. 37]).
	At present it is only speculation about the sources solar radiation-belt		At present it is only speculation about the sources solar radiation-belt
	particles, but some are surely present as cosmic-ray secondaries in		particles, but some are surely present as cosmic-ray secondaries in
Line 69:		Line 69:
	on pitch angle.		on pitch angle.
	Any increase of pressure will alter the quasi-equilibrium of the streamer,		Any increase of pressure will alter the quasi-equilibrium of the streamer,
	~~creating more open field at~~ the streamer cusp.		altering the structure of the separatrices defining the streamer cusp.
	~~But an~~ SEP event can produce a huge flux of high-energy particles,		An SEP event can produce a huge flux of high-energy particles,
	arguably enough to match the ambient streamer magnetic field and		arguably enough to match the ambient streamer magnetic field and
	thus doubling the total pressure.		thus doubling the total pressure.
Line 90:		Line 90:
	pressurizes the accessible field volume.		pressurizes the accessible field volume.
	This drives expansion and creates or augments a CME; the energy added		This drives expansion and creates or augments a CME; the energy added
	to expand the field ~~the returns~~ in the normal		to expand the field subsequently reappears in the normal
	[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]		[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]
	process.		process.

	== Conclusions ==		== Conclusions ==

	We picked the "streamer breakout" CME class because its name is so evocative,		We picked the "streamer breakout" CME class because its name is so evocative,
	~~but~~ it's quite possible that particle pressure is not the definitive		though it's quite possible that particle pressure is not the definitive
	mechanism in this case.		mechanism in this case.
	But the important message here is that non-thermal particle pressure can have a		But the important message here is that non-thermal particle pressure can have a

Streamer Blow-out CMEs and Particle Pressure

Hhudson — Tue, 23 Jun 2026 09:11:26 GMT

Created page with "{{Infobox Nugget |name = Nugget |title = Streamer Blow-out CMEs |number = 529 |first_author = Hugh HUDSON |second_author = Ed CLIVER |publish_date = June 22, 2026 |next_nugget = TBD |previous_nugget = {{#ask: Category:Nugget RHESSI Nugget Index::528}} }} == Introduction == We know about solar energetic particles [https://en.wikipedia.org/wiki/Solar_energetic_particles (SEPS)] from many observations from instruments on space probes, and also from ground-based..."

New page

{{Infobox Nugget |name = Nugget
|title = Streamer Blow-out CMEs
|number = 529
|first_author = Hugh HUDSON
|second_author = Ed CLIVER
|publish_date = June 22, 2026
|next_nugget = TBD
|previous_nugget = {{#ask: [[Category:Nugget]] [[RHESSI Nugget Index::528]]}}
}}

== Introduction ==

We know about solar energetic particles
[https://en.wikipedia.org/wiki/Solar_energetic_particles (SEPS)]
from many observations from instruments on space probes, and also from
ground-based observations such as those of
[https://neutronm.bartol.udel.edu/ neutron monitors].
SEP events occur only intermittently, often following powerful flares, and
when they do occur the particle fluxes far exceed those of the
[https://news.uchicago.edu/explainer/what-are-cosmic-rays cosmic rays],
even out to GeV energies.
We cannot make in situ observations anywhere close to the Sun, and
the propagation of these "solar cosmic rays" throughout the
[https://en.wikipedia.org/wiki/Heliosphere heliosphere]
remains somewhat mysterious.
But we can tell that the highest-energy particles come from acceleration
mechanisms deriving energy from
[https://spaceplace.nasa.gov/sun-corona/en/ §coronal magnetic fields].
Therefore SEPs are probably present in the low corona at times.
This Nugget discusses one potential consequence of SEPs near the Sun.

== Solar radiation belts ==

By analogy with the Earth's radiation belts, energetic particles can be trapped
in the Sun-girdling streamer belt
of closed magnetic fields (Ref. [1]), satisfying all three of the
[https://en.wikipedia.org/wiki/Adiabatic_invariant adiabatic invariants]
that allow the
[https://physics.uiowa.edu/about/james-van-allen Van Allen]
belts to exist.
At present it is only speculation about the sources solar radiation-belt
particles, but some are surely present as cosmic-ray secondaries in
high-energy interactions.

Shock-wave acceleration of SEPs gives us another
likely source of particles for solar radiation belts.
Modeling (e.g., Ref. [2]) clearly points to efficient shock acceleration
within streamer volumes.
Figure 1 illustrates one geometry (shock origin external to the streamer),
but flare/CME sources may occur within the streamer domain as well, in the
form of the "spine-and-fan" magnetic geometry of
[https://en.wikipedia.org/wiki/Active_region "anemone"]
active regions.

[[File:529f1.png|center|thumb|600px|caption|Figure 1: 
Sketches showing global waves emitted from the low corona:
[https://www.astro.gla.ac.uk/cartoons/Vainio-Khan_2004ApJ...600..451V_CME.html left],
showing the flank of a wave moving laterally, but somehow not entering
closed-field regions; and
[https://www.astro.gla.ac.uk/cartoons/Wild-1969_1969PASAu...1..181W_PHY.html right],
remedying that omission.
]]

== Particle pressure and "streamer blow-out" events ==

If global shock waves crossing streamers can leave trapped high-energy
particles within closed-field regions, what will happen?
The particles either precipitate or augment the plasma pressure, depending
on pitch angle.
Any increase of pressure will alter the quasi-equilibrium of the streamer,
creating more open field at the streamer cusp.
But an SEP event can produce a huge flux of high-energy particles,
arguably enough to match the ambient streamer magnetic field and
thus doubling the total pressure.
For example, 1033 protons at 100 MeV contain only 1030
erg, but exert the pressure of an 0.1 Gauss field in a volume RSun3.
In such a case one would probably see a "streamer blow-out" CME;
Figure 2 shows how such an event, also called a "bugle", appears
in synoptic coronagraph data.

[[File:529f2.png|center|thumb|500px|caption|Figure 2: 
Synoptic coronagraph data for one month in 1997, illustrating the time developments
of streamers.
Time runs from right to left as the Sun rotates; the streamer disappearing in
the indicated blow-out first grows in brightness for a few days, and then suddenly
disappears.
]]

This mechanism seems plausible; an impulsive flare accelerates SEPs, which
pressurizes the accessible field volume.
This drives expansion and creates or augments a CME; the energy added
to expand the field the returns in the normal
[https://www.astro.gla.ac.uk/cartoons/cshkp.html CSHKP]
process.

== Conclusions ==

We picked the "streamer breakout" CME class because its name is so evocative,
but it's quite possible that particle pressure is not the definitive
mechanism in this case.
But the important message here is that non-thermal particle pressure can have a
powerful effect on magnetic structures in the solar corona in general.
This mechanism must be functioning, since we observe SEPs and can infer their
presence the corona.
MHD simulations in general cannot paint a complete picture of coronal
dynamics without recognizing this elementary consideration.
The rather poor older-style graphics in this Nugget reflect the fact that we
could have come to this conclusion decades ago!
The dramatic discovery soft X-ray detection of dimming at the very
bottom of the corona (e.g., Ref. [3]) should have sent this clear message
already.

== References ==

[1] [https://ui.adsabs.harvard.edu/abs/2009ApJ...698L..86H/abstract "Coronal Radiation Belts"]

[2] [https://ui.adsabs.harvard.edu/abs/1982SSRv...33..219S/abstract "Observations of coronal structure during sunspot maximum"]

[3] [https://ui.adsabs.harvard.edu/abs/1997SoPh..175..601D/abstract "EIT and LASCO Observations of the Initiation of a Coronal Mass Ejection"]

File:529f2.png

Hhudson — Tue, 23 Jun 2026 09:08:15 GMT

Hhudson uploaded File:529f2.png

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File:529f1.png

Hhudson — Tue, 23 Jun 2026 09:07:39 GMT

Hhudson uploaded File:529f1.png

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