a thoughtful web.
Good ideas and conversation. No ads, no tracking.   Login or Take a Tour!
comment
am_Unition  ·  914 days ago  ·  link  ·    ·  parent  ·  post: Look for a nice aurora on Thursday (April 14)

So uh. Typically, large coronal mass ejections are produced by clusters of big,

magnetically complex

sunspots.

Over the next few days, those badbois (2993, 2994, and 2995) are gonna rotate into geoeffective position, from the left side of the earth-facing solar surface into the center-right area. Unintuitively, we would call this "from East to West", because the prevailing convention is to affix East to Earth's duskward direction, and West to dawnwards. At least geometric/astronomical North and South are consistent between the Earth and sun. But, of course, the Earth's North pole is actually a magnetic South pole, by convention (field lines go "into" the Earth's "North" pole and "out of" Earth's "South" pole). And to think, if we woulda just decided electrons were mathematically positive and protons negative, North would be North. At least for now, until the poles reverse again in another hundred thousand years or so.

Also worth noting that so far solar cycle #25 is very much outperforming expectations:

BTW, I think we should formalize a better method than counting sunspots for quantifying solar activity (total solar irradiance might be part of it), but of course also keep sunspot number, since comparisons with the historical record are so valuable.

Hopefully this is the last comment I make here.