Secrets Behind Sunquakes Could Lurk Beneath the Solar Surface


Jan. 4, 2021

A secret behind the workings of sunquakes – seismic activity on the Sun during solar flares – might be hidden beneath the solar surface.

These earthquake-like events release acoustic energy in the form of waves that ripple along the Sun’s surface, like waves on a lake, in the minutes following a solar flare – an outburst of light, energy, and material seen in the Sun’s outer atmosphere.

Satellite images of the Sun's surface show rippling concentric waves.

Movie of a sunquake – the earthquake-like waves that ripple through our star. Left frame shows the active region in visible light (amber) and extreme ultraviolet (red) on July 30, 2011. Right frame shows the ripples on Sun’s outlying surface up to 42 minutes after the onset of the flare, which is marked by the label “IP” for impulsive flare.Credits: NASA/SDO

Scientists have long suspected that sunquakes are driven by magnetic forces or heating of the outer atmosphere, where the flare occurs. These waves were thought to dive down through the Sun’s surface and deep into its interior. But new results, using data from NASA’s Solar Dynamics Observatory, have found something different.

In July 2011, SDO observed a sunquake with unusually sharp ripples emanating from a moderately strong solar flare. Scientists were able to track the waves that caused these ripples back to their source, using a technique called helioseismic holography. This technique, which used SDO’s Helioseismic and Magnetic Imager to measure how the solar surface was moving, has previously been used to track acoustic waves from a variety of other sources in the Sun.

Instead of the waves traveling into the Sun from above, the scientists saw the surface ripples of a sunquake emerging from deep beneath the solar surface right after a flare occurred. The results, published in the journal Astrophysical Journal Letters, found the acoustic source was around 700 miles below the surface of the Sun – not above the surface as previously was thought.

The scientists believe that these waves were driven by a submerged source, which was in turn somehow triggered by the solar flare in the atmosphere above. The new findings might help explain a long-standing mystery about sunquakes: why some of their characteristics look remarkably different from the flares that trigger them.

The scientists still haven’t identified exactly what mechanism actually causes sunquakes, though the results do provide the clue that their origins likely lurk beneath the surface. The scientists plan to continue searching for a mechanism by looking at other sunquakes to see if they have similarly submerged sources.

Solar Flares Set the Sun Quaking
Learn more about SDO

By Mara Johnson-Groh
NASA’s Goddard Space Flight Center, Greenbelt, Md.Last Updated: Jan. 4, 2021Editor: Lina Tran

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January 4, 2021 10:15 pm

The Iron Sun?

Last edited 2 months ago by Philip Mulholland
Leif Svalgaard
Reply to  Philip Mulholland
January 4, 2021 10:33 pm

No. That is complete nonsense.

Reply to  Leif Svalgaard
January 4, 2021 10:46 pm

Nothing to see here? Move on.

Reply to  Philip Mulholland
January 5, 2021 2:23 am

Analogy is totally false, no tectonic plates up there. These events are in final analysis are due to thermonuclear processes (fusion) very deep in the core and slowly percolate towards the surface.

Leif Svalgaard
January 4, 2021 10:21 pm

We have known for some time[e.g. ] that the [magnetic] energy that powers solar flares [and associated sunquakes] must come from the deep interior of the sun. So the finding in the post is not a surprise.

Reply to  Leif Svalgaard
January 4, 2021 11:06 pm

Science is about exploring ideas, not about dogma.
Manuel, O.K. 2017 The Universe is in Good Hands

Last edited 2 months ago by Philip Mulholland
Reply to  Philip Mulholland
January 5, 2021 4:54 am

Science is about exploring ideas and then dismissing those that are complete nonsense, as complete nonsense.

Joel O’Bryan
Reply to  Leo Smith
January 5, 2021 1:30 pm

gastro enterology dismissed as nonsense the idea that peptic ulcers had a pathogenic bacterial etiology and could be resolved in > 95% cases with cheap doxycycline or similar antibiotics. cheap antibiotics destroyed a medical cottage industry of gastric resection surgery overnight.

Loren C. Wilson
Reply to  Joel O’Bryan
January 6, 2021 4:36 am

It’s hard to convince people of something when their paycheck depends on it not being true.

Patrick MJD
January 4, 2021 11:27 pm

Does it affect “climate” (Avg 30yrs weather as per IPCC)?

January 4, 2021 11:28 pm

Not all solar flares are associated with sunquakes. I presume the ratio of sunquakes to flares of M1 XRay classification will vary among different years; but read it has been as low as merely ~20% of that category of flares exhibiting sunquakes.

Furthermore often the stronger X classified flares did not have sunquakes, or still only have less remarkable sunquakes than X-class flares comparatively less strong. Apparently it is usually the more moderately intense flares that seem to actually be the ones which better promptly channel the impulses coming (as per original post) from below into sunquakes.

Joel O’Bryan
January 4, 2021 11:48 pm

This group’s findings are consistent with my GW-solar active region hypothesis.
My GW-solar flare AR hypothesis posits that gravitational waves of sufficient strength induce a set of standing waves in ultra high pressure magnetic thin flux tubes rising off the tachocline. The standing wave points with modes of higher amplitude oscillations between induce buoyancy differentials causing sections to rise through the convective zone a bit faster than adjacent sections. The buoyancy differential under the alpha effect (differential rotation) induces the twisted magnetic fields that characterize beta gamma and beta gamma delta active reguons near the surface.
The stronger the GW, the more the deep flux tubes are “plucked” like a harp string. Of course this strong GW thin flux tube excitation appearance at the surface is also dependent on the Sun’s 11 year long Schwabe magnetic state.
These strong GWs emanate from deep cosmic space (100’s of mega-parsecs typically) produced by binary black hole (bbh) inspirals and from binary neutron star (bns) inspiral mergers (much lower mass GW events than BBH but necessarily being much closer relative to BBH inspirals). Only the strongest GW chirps from deep intergalactic space produce the necessary tachocline flux tube string plucks to ultimately produce solar bgd active regions, per this hypothesis.

This is a testable hypothesis with the ALIGO Virgo Geo400 KAGRA GW interferometry collaboration. The Sept 2017 AR flaring was tied to both strong BBS and BNS detected GW events in August. The fkux tube rise time through the CZ provides the delay between GW and region emergence on the visible solar surface. Same with the original, seminal Sept 2015 strong BBH GW discovery.
Einstein’s GR posited polarization of GW’s means flux tube excitation is maximal on horizontal flux tubes deep in the CZ and on limb oriented near surface vertically aligned flux structures to the arrival vector (HA, Lat) of the GW through the solar sphere. Thus there is an early phase (1-4 days) of limb oriented magnetic flux structures excitation and a delayed phase at 14-18 days from GW evenr (delay due to flux tube rise time from near tachocline) of flaring from strong GW events.

Currently my best estimate for a strong GW is (solar mass evaporated as GW energy)/(distance in Giga LY)^2 > 1.0.

Last edited 2 months ago by joelobryan
Peta of Newark
Reply to  Joel O’Bryan
January 5, 2021 12:40 am

Wow, I was thinking just the same thing.
I’m no expert on harps tho, I was thinking of bungee cords or tie-wraps attached to cow farts
Probably explains why the di-lithi-tani-lanium fuggulator of my supper massive Spotnik had a batt flattery as it made a close approach to take a sample.

And it melted.
No matter, furetr research will mdoel the eqoobum sensivittity for back-force feed e-funk of the Gas Gas Efart Intent, thus confirming that the sun has a tempertaure of 5,621.42 Kevlars and not 5,621.97 Kelvar as projeviously prefectetd.

There, now that’s settled

Last edited 2 months ago by Peta of Newark
Rod Evans
Reply to  Peta of Newark
January 5, 2021 3:32 am

Thanks for clarifying those little points in Joel’s missive on solar energy interactivity with itself.
Now, can you help out with why the solar atmosphere is millions of degrees K yet the surface is only the now clarified 5,621.42 “Kevlars” as you confirm. I only ask because that missing 0.55 deg Kevs will make the disparity between the radiating body and the ethereal solar atmosphere that much more difficult to rationalise??
Maybe it is just “quantity” theory?

Reply to  Rod Evans
January 5, 2021 4:54 am

JPL’s Dr Barry Centre has a paper on the subject, worth a look (have no link, google it).

very old white guy
January 5, 2021 3:51 am

someone should go up and check it out.

January 5, 2021 5:54 am

It just proves Dr. Lerner’s observation, that cosmology must come back to the Lab.
Dealing with fusion plasma here will bring the insights necessary.
And a fusion propulsion system might use “quakes” for pulsed power, so well worth studying.
To suggest validating this against other stars, seems to be pie in the sky.
Get back to the lab!

Gordon A. Dressler
January 5, 2021 7:05 am

Scientists have spent decades and many millions (billions?) of dollars using supercomputers with advanced physics-based modeling of solar processes. Surely, there cannot be any “secrets” or surprises that the models have missed. Surely.

/sarc off

Loren C. Wilson
Reply to  Gordon A. Dressler
January 6, 2021 4:42 am

Agreed. Since the physics in the Sun are better known than the physics of our climate (unknown inputs at least), they should be able to do a better job of modelling its behavior. This should be a cautionary tale for climate modelers, but alas.

Jackie Pratt
January 12, 2021 4:47 pm

Damn! All that wasted time I spent at Keck observing Jupiter, to explain this phenomena…….

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