[SFDXA] SOLAR FLARE FRENZY

[Bill]

*SOLAR FLARE FRENZY:* Yesterday, May 22nd, sunspot AR2824 unleashed a 
flurry of solar flares unlike anything we've seen in years. NASA's Solar 
Dynamics Observatory recorded 9 C-class 
<https://www.spaceweather.com/glossary/flareclasses.html> flares and 2 
M-class <https://www.spaceweather.com/glossary/flareclasses.html> flares 
in only 24 hours. Click on this animation of a single explosion to see 
the entire day:

<https://www.spaceweather.com/images2021/22may21/frenzy.gif>

The rapidfire explosions hurled multiple overlapping CMEs into space. 
NOAA analysts are still untangling the clouds to determine if any might 
hit Earth. So far, none appears to be squarely Earth-directed, but 
glancing blows are possible starting on *May 26th*. Stay tuned for 
updates. *Solar flare alerts:* SMS Text <https://spaceweatheralerts.com>.

*HUGE SOLAR RADIO BURST:* During yesterday's solar flare frenzy, the sun 
emitted a shortwave radio burst so loud that "it drowned out lightning 
static from a severe local thunderstorm," reports Thomas Ashcraft, who 
recorded the signal using a radio telescope in rural New Mexico. Click 
to listen to a 100 second sample:

<https://www.spaceweather.com/images2021/22may21/SunMay222021_2130UT22.21MHz_Ashcraft.SW.mp3>
View the dynamic spectrum 
<https://www.spaceweather.com/images2021/22may21/dynamicspectrum.png> or 
listen to the audio 
<https://www.spaceweather.com/images2021/22may21/SunMay222021_2130UT22.21MHz_Ashcraft.SW.mp3>

The radio burst coincided with an M1.4-class 
<https://www.spaceweather.com/glossary/flareclasses.html> solar flare at 
21:30 UT. "This was a very hot and dynamic flare for sure," says 
Ashcraft. "I was recording audio at 22 MHz and 21 MHz, and my radio 
spectrograph was operating from 30 MHz down to 15 MHz. Strong solar 
radio emissions were present at all frequencies."

Astronomers classify solar radio bursts into 5 types 
<https://en.wikipedia.org/wiki/Solar_radio_emission#Solar_radio_bursts>. 
Ashcraft recorded Type II 
<https://www.atnf.csiro.au/pasa/17_1/cairns/paper/node5.html> and Type V 
<https://link.springer.com/article/10.1007%2FBF00152480>. These are 
caused, respectively, by shock waves and electron beams moving through 
the sun's atmosphere in the aftermath of strong flares.

"The sun has been in a state of Type III 
<https://www.frontiersin.org/articles/10.3389/fspas.2020.00056/full> 
radio storming for the past three days with near continuous emissions," 
says Ashcraft. "It is possible this sunspot region will produce more 
activity. I will be listening and watching."

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