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X5.1 solar flare, G4 geomagnetic storm watch

spaceweatherlive.com

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Re: X5.1 solar flare, G4 geomagnetic storm watch

#22

Post by superkuh »

We won't know any actionable detail till about 1 hour before it arrives at Earth. That's when interplanetary coronal mass ejections actually have their magnetic field orientation and intensity measured by ACE and other satellites far out at the L1 lagrange point: https://services.swpc.noaa.gov/images/ace-mag-swepam-24-hour...

If you see the red line on this plot^, the interplanetary magnetic field, be more than -10 nanotesla for about 4 hours then there's a good chance of lower than normal latitude aurora. Negative means the magnetic field is pointing downwards out of the ecliptic plane of the solar system and this is the most energetically favorable orientation for reconnecting CME magnetic field lines with Earth's magnetic field lines and letting solar particles/energy in.

It can be 20nT positive (upwards) magnetic field with intense density and high velocity but still be a non-event aurora-wise just because energy is delivered to the Earth's ring currents at 10x slower rate than if it's pointing downwards.

None of the WSA-ENLIL or related predictive models take into consideration the magnetic field orientation of iCMEs because it's really hard to know from remote observations. They can be thought of as warnings to pay attention to the ACE L1 measurements.

Re: X5.1 solar flare, G4 geomagnetic storm watch

#23

Post by CoastalCoder »

deskamess wrote: post #16
aaronmdjones wrote: post #8

Earlier quoted context omitted.

16 hundred hours; 16:00. Since revised down to midday (12 UTC). https://www.swpc.noaa.gov/sites/default/files/styles/pad_sid...

Bad timing for North America Eastern TZ - day break here. Pacific/Mountain TZ should be fine.

In Rhode Island it seems like auroras practically guarantee overcast skies.

Update: tonight the sky is clear and the air is frigid. I guess this logically implies there won't be an aurora :)

Re: X5.1 solar flare, G4 geomagnetic storm watch

#25

Post by sva_ »

abujazar wrote: post #2

Also: 100 % cloud cover in basically all of Northern Europe :/ Iceland is probably the place to be for the aurora show!

In northern Germany, it seems like clouds will clear up tomorrow night, when the CME arrives, according to meteoblue? I can only hope.

Re: X5.1 solar flare, G4 geomagnetic storm watch

#26

Post by hdgvhicv »

lukan wrote: post #19
thebruce87m wrote: post #13

Earlier quoted context omitted.

Note to non-UK readers: Most of the time when someone says they are in the “North East of the UK” it’s not some Scotsman up in Shetland it is an English person who is currently in the North East of England. The North East of England is in the middle part of the UK mainland.

So .. they don't see scotland as part of the UK anyway? Why was it such an issue then that they wanted to leave? (And why were there bloody wars fought about it in the first place?)

Who wanted to leave? What wars?

Re: X5.1 solar flare, G4 geomagnetic storm watch

#27

Post by permo-w »

lukan wrote: post #19
thebruce87m wrote: post #13

Earlier quoted context omitted.

Note to non-UK readers: Most of the time when someone says they are in the “North East of the UK” it’s not some Scotsman up in Shetland it is an English person who is currently in the North East of England. The North East of England is in the middle part of the UK mainland.

So .. they don't see scotland as part of the UK anyway? Why was it such an issue then that they wanted to leave? (And why were there bloody wars fought about it in the first place?)

I think most people say "the North East" as a synecdoche for "the North East of England". the commenter being referred to likely just misspoke

Re: X5.1 solar flare, G4 geomagnetic storm watch

#29

Post by kjs3 »

hdgvhicv wrote: post #26
lukan wrote: post #19

Earlier quoted context omitted.

So .. they don't see scotland as part of the UK anyway? Why was it such an issue then that they wanted to leave? (And why were there bloody wars fought about it in the first place?)

Who wanted to leave? What wars?

Someone with a tiny little...um...axe to grind and not enough sense to take it someplace where people care. You can tell when they have to go back to Culloden to try and drag something up to wave around.
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