NASA | X-Class: A Guide to Solar Flares

Flares happen when the powerful magnetic fields in and around the sun reconnect. They're usually associated with active regions, often seen as sun spots, where the magnetic fields are strongest. Flares are classified according to their strength. The smallest ones are B-class, followed by C, M and X, the largest. Similar to the Richter scale for earthquakes, each letter represents a ten-fold increase in energy output. So an X is 10 times an M and 100 times a C. Within each letter class, there is a finer scale from 1 to 9. C-class flares are too weak to noticeably affect Earth. M-class flares can cause brief radio blackouts at the poles and minor radiation storms that might endanger astronauts. Although X is the last letter, there are flares more than 10 times the power of an X1, so X-class flares can go higher than 9. The most powerful flare on record was in 2003, during the last solar maximum. It was so powerful that it overloaded the sensors measuring it. They cut-out at X28. A powerful X-class flare like that can create long lasting radiation storms, which can harm satellites and even give airline passengers, flying near the poles, small radiation doses. X flares also have the potential to create global transmission problems and world-wide blackouts.


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[gilraen]

A day when I learn something is a good day. Thank you, NASA.

[Junkiang]

@JoelTM347 I am a Chinese, I have to say, the American scientists have done a lot for the whole human race's benefit by doing research on subjects like the one in the video. All people should thank them.

[Aspharon]

So, what would've happened if that X40-something flare DID hit the earth? Global blackout? Is there a maximum to the power of solar flares? if so, what would happen if a flare with maximum power would hit earth?

[lighttowers]

(3) and indicator that these proton eruptions must happen deep inside the sun/ near its core?. The proton event on 20110308 occured after the sun activity had risen for three (hot and dry)weeks without any larger flare or CME same with latest events in 2012- gravity increases? Also proir and after to dec 26 2004 there were several strong proton STORMS mostly followed then by larger eruptions .

[squidb]

Doesn't a flare take just minutes to reach earth. How do you prepare for that?

[sudhabathula]

And it's happening today, worth to mention its x class 😶 don't know should I laugh or cry being a space enthusiast

[infotechsailor]

the last line of this video is the worst scenario can never happen that seems pretty unscientific considering the various X class possibilities

[Astrostevo]

Thanks NASA - good breif explanatory clip here. Appreciated. :-)

[RajKumar-qgiv]

It's occurring today. Note my timestamp

[lighttowers]

@nasa. (1) in this viedeo you don`t refer to coronal mass ejections. There was f.i. an about 30° earthward directed X 8 flare in 2011, from which everyone expected it would create a large CME .But there was nothing at all. as it seems by comparisation: as larger the flare as smaller the CME.I started to follow these solar activities, after it became obvious that the Honshu earthquake on 20110311was anyway related to two major CMEs those arrived the days before.

[jacquelinejacqueline]

Black out will bring back all magical things 😉💚🌞💙💪🏼

[lighttowers]

(2)all impacting CMEs effect on the tectonic plates and rise volcanic activites and eq, even storms as all statistics showed but much larger flares did nothing comparable to the Honshu quake .It took me a while and some data reviews until it became clear. The mar 08 cme was accomponied by a seldom PROTON STORM. . the last proton outburst occured along with a backside eruption on Nov 08- 2012 But protons were emmited into all directions and without any Earth directed CME

[NJCProductions]

Old great, now we're going to need a gigantic faraday cage.

[torquemenistan]

You all know that, in the distant future, space could be our last resort yea?.. A very distant future.

[DavidOD]

I was just wondering because I'm still not sure how northern lights are formed but if there was an X class flare which I know is rare but would there be northern lights worldwide?

[Astrostevo]

@heartlessvietboy : The best "map" to look at for that would be a globe of the world. The Pacific Ocean takes up nearly half our planet. The Earth is indeed about two-thirds covered with oceans and seas -and rather misnamed! We should have called our world "Water" instead. ;-)

[water-shrimp]

I hears we're getting hit with one today. Monday july 12, 2021

[EzacK]

@snails40 Compared to what goes into the wars? The cost of the wars is much more than all of NASA's budget since the start of the program. $700 Million is nothing.

[kharnakcrux]

i wonder how big a Flare is needed.... to strip Earth's atmosphere

[Hyumanity]

Thank you guardians of planet Earth :D