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Greatluster t1_je38zih wrote

Reply to comment by william_patino in Aurora Australis, New Zealand {OC} (1500x1000) by william_patino

How do you know when there’s going to be an aurora?

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Taco_El_Paco t1_je39srw wrote

Solar flares. More due this Friday and Saturday courtesy of a hole in the sun that was observed yesterday

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ForgottenPercentage t1_je3sbu5 wrote

It is not as simple as solar flares. Not all solar flares produce CMEs. You need a solar flare that causes a coronal mass ejection (CME) which releases many particles to cause a good Aurora. Solar flares also come in varying magnitudes with M# and X# class flares being the strongest.

The CME needs be earth facing and preferably the interplanetary magnetic field is showing a negative Bz so that the interaction from the solar wind (CME) and earth's magnetic don't repel eachother.

Ofc you also want a cloudless night.

The sun is approaching solar maximum and is estimated to occur July 2025. This means increased sun activity, which means more sun's spots which means more flares and more chances for powerful earth facing CMEs. The sun goes through a solar minimum - maximum cycle on average every 11 years.

I use solarham.net and space weather to track sun activity for Auroral events.

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Yadobler t1_je4c52i wrote

But does CME happen without solar flares?

If so then seeing solar flares (which you can only see if it's facing the earth) is a good enough guage to approximate if AA or AB is happening.

Or in the contrapositive, no solar flare -> no AA

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ForgottenPercentage t1_je4s5r8 wrote

CMEs can occur without solar flares although most large CMEs coincide with solar flares. It's not a well understood phenomenon.

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thisismyaccount3125 t1_je7li3h wrote

>July 2025

Noted.

also kinda temporarily forgot what year it was, panicked cause I didn’t know if this was one year or five years away for a second, both incorrect.

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william_patino OP t1_je47f0g wrote

Check my YouTube channel for more of a ELI5 answer. Link is in the comments or just search my name there :)

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