Comment by ChuckMcM | Hacker News Reader

Comment by ChuckMcM | Hacker News Reader

Very cool. Its amazing what we don't know about the star sitting just 8 light minutes away from us.

For jnorthrop generally these events are effectively deflected by the Earth's magnetosphere, however we don't know what we don't know. Its hard to estimate whether or not any one of the extinction events this planet has experienced over the past was caused by solar activity.

I would hope it would add impetutus to efforts to surviving large changes in the Earth's envioronment by creating completely controlled environments (ideally across several planetary bodies) but I have low expectations that it will.

One of the science stories I've been following for a while has been the growing body of evidence that a magnetic pole reversal [1] is becoming more likely. (Note there was a hoax around it changing instantly in 2012 which has been pretty thoroughly debunked). One thing that is pretty well understood is that during reversals the magnetosphere is greatly reduced [2] which suggests that the simulataneous occurence of a CME and a reversal of the poles resulting in a reduced magnetosphere would be something to write home about.

[1] http://www.nasa.gov/vision/earth/lookingatearth/29dec_magnet...

[2] http://www.off-ladhyx.polytechnique.fr/people/willis/papers/...

And you would have to write, unless there is significantly more tolerance in our digital network!

With large solar flares there have been reports of telegraph wires having such large currents induced that the telegraph paper caught on fire from the sparks generated! [1]

Just imagine what these currents would do to modern sensitive electronics... And I suspect that there hasn't been that much thorough testing in consumer-level hardware, although power and communication companies are very aware of the problems and have changed the designs of some systems to handle these events better (as in "let's not melt the power grid quite as bad...")

[1] http://science.nasa.gov/science-news/science-at-nasa/2008/06...

"The northern lights were unusual enough but then worldwide telegraph systems started going out. Telegraph operators were being shocked unconscious and the flying sparks from the telegraph machines were setting the papers and their machines on fire. When the telegraph operators disconnected their machines from the batteries, there were still sparks flying. This is because the power of solar flares induced electricity into the lines that carried the telegraph signals from one telegraph station to the next. This became known as the Carrington Event."

http://factoidz.com/could-another-carrington-event-destroy-o...

http://www.overcomingbias.com/2009/06/space-storm-insurance....

Kinda puts me off sitting here with my headphones on...

I wouldn't think that most sensitive electronics is big enough to really be affected, you need a closed circuit that encloses a significant area. For the telegraph (and modern electrical grid) that would be the height that the wires are strung at times the length of the wires. Anything that fits in your home is probably safe, unless your network cables have shielding that's grounded at both ends with no series resistance or something.

The electrical disturbances don't need to be introduced into the electronics directly though - if the flare induced enough disturbance into the national grid, then all sorts of strange induced currents could appear on your mains voltage, and wreak havoc with inadequately filtered power supplies.

We rely on mains power to arrive at a nice even 50-60Hz, with the voltage varying a few percent. Sensitive electronics are designed to filter out this low frequency, but higher frequencies may well pass through into other circuits that weren't designed for it, with unknown consequences.

It'd likely fry transformers before they started detonating things in your home, though. The induced current on the path from the transformer to your house couldn't be that big.

Still, it's an interesting thought. With how fragile the power infrastructure is in North America, it could cause some serious problems.

In 1989 the Quebec province power grid was brought down for some hours following important solar activity. Like you said for consumers it was simply a black out. As for the power infrastructure I think they made important changes to make it more resistant (in Quebec), but I don't have more details.

What about optical technology? Would that be affected?

(yes, I know currently there is always at some electronical parts, but I mean in theory)

Early telegraphs didn't use a ground wire, the return path was literally the Earth. Modern systems with differential signals on a twisted pair are many orders of magnitude less affected.

It's amazing what we don't know about things sitting just a few light seconds away at most, too, such as the depths of the oceans or the spiders in my backyard.

I think they're working on the 'bases on other planetary bodies' backup plan, but it will be a few years.

Just FYI, The circumference of earth is roughly 4 * 10^7 metres, and the speed of light is 3 * 10^8 m/s, so light can actually circle the globe almost 7.5 times per second.

The depths of the oceans are just a few milliseconds away (40ms -ish?).

I figured it was something like that. Certainly explains why my ping to London is under 100 ms, right?

Yup. My Telecommunications prof back in University told us you can approximate the speed of a network as 2c/3, so that sounds right on the button.

http://www.wolframalpha.com/input/?i=depth+of+challenger+dee...

http://www.wolframalpha.com/input/?i=time+for+light+to+trave...

40 µs, not ms.

(off topic.. can anyone get wolfram alpha to answer that in one query?)

"Depth of Challenger Deep in light seconds"

I was going for the distance from some arbitrary spot in North America to some arbitrary spot way out in the middle of the Pacific Ocean, where I'd assume the ocean is at its deepest, but this is interesting too.

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