APOD: A Powerful Solar Flare (2018 Sep 02)

[APOD Robot]

A Powerful Solar Flare

Explanation: It was one of the most powerful solar flares in recorded history. Occurring in 2003 and seen across the electromagnetic spectrum, the Sun briefly became over 100 times brighter in X-rays than normal. The day after this tremendous X 17 solar flare -- and subsequent Coronal Mass Ejection (CME) -- energetic particles emitted from the explosions struck the Earth, creating auroras and affecting satellites. The spacecraft that took these frames -- SOHO -- was put in a turtle-like safe mode to avoid further damage from this and subsequent solar particle storms. The featured time-lapse movie condenses into 10 seconds events that occurred over 4 hours. The CME, visible around the central sun-shade, appears about three-quarters of the way through the video, while frames toward the very end are progressively noisier as protons from the explosions strike SOHO's LASCO detector. One this day in 1859, the effects of an even more powerful solar storm caused telegraphs on Earth to spark in what is known as the Carrington Event. Powerful solar storms such as these may create beautiful aurora-filled skies, but they also pose a real danger as they can damage satellites and even power grids across the Earth.

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[Holger Nielsen]

Note the overexposed image of Mercury at about 10 o'clock drifting slowly to the left after superior conjunction with the Sun on October 25, 2003.

[E Fish]

That CME gave me my first and so far only glimpse of an aurora. I was in northern Utah and hadn't even realized that it was possible. That's quite an amazing video.

[BDanielMayfield]

That CME gave me my first and so far only glimpse of an aurora. I was in northern Utah and hadn't even realized that it was possible. That's quite an amazing video.

Then I've moved far enough north to have a reasonably good chance of seeing one too from a location a few hundred miles north in Idaho.

[Chris Peterson]

That CME gave me my first and so far only glimpse of an aurora. I was in northern Utah and hadn't even realized that it was possible. That's quite an amazing video.

Then I've moved far enough north to have a reasonably good chance of seeing one too from a location a few hundred miles north in Idaho.

The last few solar max cycles have produced auroras as far south as Arizona. The thing is, two or three aurora events over several years means they are very easily missed. And at this point, it's uncertain what the next few solar max cycles are going to look like. There are credible predictions they will be weaker than usual. So who knows? But I've seen eight or ten nice auroras (and a lot more photographic ones) in central Colorado over the last 15 years. The trick is to stay on top of the solar weather and be prepared. Even with a less active Sun, you should definitely be able to catch some auroras from your latitude if you look out for the right conditions.

[ta152h0]

Vasco da Gama, errrr Vasco da Parker must be approaching the sun.

[heehaw]

I hope I'm deep underground when the next big one hits us. That last frame with all the little white strips of particle hits is frightening.

[De58te]

I hope I'm deep underground when the next big one hits us. That last frame with all the little white strips of particle hits is frightening.

You don't need to be underground since all biological life on Earth is protected by Earth's Magnetic Field. Unless your life is depended on electronic life support, then I'd worry. Also if you are on a plane that happens to be too far away from any airport that it can glide in to. Trains are OK since they'd just coast to a stop. What you'd need to do is learn how to make a fire by rubbing two sticks together to cook your food because they said it would take from 6 months to a year to restore the electrical grid. Most food that is refrigerated has only a week or so use by date. So you need to learn how to grow food from seed and also need a hunting rifle to hunt deer. You also need a manual hand water pump because electric pumps won't work. You'd also need to have at least a 6 months supply of cash money because plastic credit cards won't work. How would you pay rent to your landlord if you didn't have cash? Will he accept your personal check when the banks are down?

[Chris Peterson]

I hope I'm deep underground when the next big one hits us. That last frame with all the little white strips of particle hits is frightening.

You don't need to be underground since all biological life on Earth is protected by Earth's Magnetic Field.

Only partly protected. Plenty of high energy particles still make it to the ground during events like this. Enough to do biological damage.

Electronics aren't at much risk, nor things like airplanes. The fields are strong enough. The two main vulnerabilities are the power grid with its long conductors, and space assets, with their greater exposure. Failures in the latter could lead to seriously damaged computer networks and other communication systems, as well as services which depend on them (like banking). Your computer and well pump and car will still be fine.

[Sa Ji Tario]

And those who live subject to electrical appliances and / or pacemakers?

[Chris Peterson]

And those who live subject to electrical appliances and / or pacemakers?

Few electrical appliances would be affected, outside of the loss of grid power. Pacemakers would not be affected at all.

[neufer]

I hope I'm deep underground when the next big one hits us. That last frame with all the little white strips of particle hits is frightening.

You don't need to be underground since all biological life on Earth is protected by Earth's Magnetic Field.

Only partly protected. Plenty of high energy particles still make it to the ground during events like this. Enough to do biological damage.

Electronics aren't at much risk, nor things like airplanes.

<<There is no substantive scientific evidence to suggest that energetic proton events are harmful to human health at ground levels, particularly at latitudes where most of the Earth's population resides. The Earth's magnetic field is exceptionally good at preventing the radiative effects of energetic particles from reaching ground levels. Humans at high altitudes, as in airplanes or space stations, risk exposure to relatively intense solar particle events. Astronauts have reported seeing flashes or streaks of light as energetic protons interact with their optic tissues. High altitude commercial transpolar aircraft flights have measured increases in radiation during energetic proton events, but a warning system is in place that limits these effects by alerting pilots to lower their cruising altitudes. Aircraft flights away from the polar regions are far less likely to see an impact from solar proton events.>>

[Chris Peterson]

You don't need to be underground since all biological life on Earth is protected by Earth's Magnetic Field.

Only partly protected. Plenty of high energy particles still make it to the ground during events like this. Enough to do biological damage.

Electronics aren't at much risk, nor things like airplanes.

<<There is no substantive scientific evidence to suggest that energetic proton events are harmful to human health at ground levels, particularly at latitudes where most of the Earth's population resides. The Earth's magnetic field is exceptionally good at preventing the radiative effects of energetic particles from reaching ground levels. Humans at high altitudes, as in airplanes or space stations, risk exposure to relatively intense solar particle events. Astronauts have reported seeing flashes or streaks of light as energetic protons interact with their optic tissues. High altitude commercial transpolar aircraft flights have measured increases in radiation during energetic proton events, but a warning system is in place that limits these effects by alerting pilots to lower their cruising altitudes. Aircraft flights away from the polar regions are far less likely to see an impact from solar proton events.>>

Most certainly, energetic proton events are harmful to human health at ground level. The point here is that such harm does not rise above the noise floor. The level and nature of the damage is not readily detectable. Certainly, some number of human cancers are caused by single energetic protons hitting the wrong cell at the wrong time. It's just not a very large number in comparison with all the other causes of cancer.