Questions about solar flares causing problems on Earth.

General Questions
#1

The recent spat of Solar activity has provoked a couple of questions from my little brain.

  1. Todays is an X18 - supposedly the 3rd largest ever. While the Earths Magnetic Fields spares the planet from most effects, could there possibly be a big enough flare/eruption that could power its way through the field and cause significant damage to us earthlings? IE - A flare the is just too big for the Earths magnetic field to handle.

  2. IIRC, the field doesn’t offer nearly as much “protection” around the magnetic poles. If a person was say, near the southern magnetic pole and under the ozone hole, would that put them in any jeoprady if a big event like todays happens?

#2

Yes, in theory, but it seems unlikely in the near future (even at the poles–the ISS astronauts in orbit aren’t even considered to be in great danger from this storm).

Our bodies aren’t really in much danger, even from a nasty nasty 1859-type storm. ( http://www.space.com/scienceastronomy/mystery_monday_031027.html ) What is in danger is our electrical/electronics (b/c magnetic fields can induce currents in conductors … and if you induce a big current in, say, something the size of the power grid, it can be bad).

Space.com has good coverage/explanation:

http://www.space.com/scienceastronomy/solar_flare_031028.html

#3

More information here:

http://www.sec.noaa.gov/NOAAscales/

#4

It is the atmosphere, not the magneitic field, that shields the earth’s surface from the harmful effects of such things.

#5

Sorry, but wrong.

Bolding mine.

#6

There are some very nice video clips of today’s flare up at the Solar and Heliospheric Observatory website.

#7

Thanks Larry. Those video’s are great.

#8

If you say so Q.E.D.. Our magnetic field likes to conduct particles to the poles. (Link).

We’ve got loads of shielding on this rock - it’s astronauts that have to worry. Flares occuring during the Apollo missions could have killed them had a mission been up during one.

Currently, both flare prediction and shielding is still pretty much handled by the cross-your-fingers-and-hope dept. Just one of the many reasons a mission to Mars is so risky.

#9

Sure, but how many people actually live at the poles?

#10

Quite a few, relatively speaking, at the South Pole.

:smiley:

#11

What exactly are the “devastating” effects that the magnetic field is protecting us from? Solar flares produce charged particles reaching tens of MeV, but that’s not enough to penetrate the earth’s atmosphere, is it? (Here are some quantitative information if anyone cares to interprit.)

One thing is for sure: the magnetic field provides absolutely no protection against X-ray and gamma ray radiation from solar flares. These are also impossible to predict because they travel at the same speed as light. (Becayse they are light.) Charged particles travel much more slowly so you can see them coming.

#12

Hrm. I think I was going to say something like that why auroras stick to the poles traditionally. Reminds me that I should take a look. Last night the aurora wasn’t so great - the entire sky was a muted green, but that was it - no definition, no swirling… I did note that it appeared there was a light meteor shower going on at the same time. Dunno what the deal was with that.

I’m wondering about the magnetic field=protection thing now too. The atmosphere would seem to be pretty good, no?

#13

Hmmm. Maybe so, but I’m going to look into this further.