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In what could potentially be one of the most, or least, significant actions of his term in office, President Trump Tuesday signed an Executive Order requiring federal agencies to strengthen critical infrastructure against ElectroMagnetic Pulse (EMP) attacks.
EMPs occur for a variety of natural and man-made reasons including, most notably, Nuclear Explosions and Coronal Mass Ejections (CMEs), either of which could potentially take out entire sections of the country's electrical grid and other infrastructure and capabilities, requiring require years or decades to recover from.
Members and supporters of the decommissioned US Commission to Assess the Threat to the United States from Electromagnetic Pulse have long warned of the possibility of an EMP attack, with some individuals, such as Peter Pry, who previously led the congressional EMP commission, asserting that an EMP attack on America could kill off 90% of the US population.
This is because a man-made EMP has the advantage of being highly asymmetrical. A small country able to pull one off would cause potentially massive disruption to a large tech dependent country such as the United States.
Past EMP related coverage here, here and here
(Score: 2, Interesting) by Anonymous Coward on Friday March 29 2019, @11:21AM (19 children)
It could also be disrupted by the sun. When Apollo 11 landed on the moon the astronauts discovered there was glass in all the craters, as if something had heated the entire surface to melt it. They dated it to the last 30k years based on the rate of turnover of the lunar surface. A layer of similar glassy substance is found all over earth and has dated to the younger dryas.
(Score: 1, Informative) by Anonymous Coward on Friday March 29 2019, @12:38PM
Source:
Apollo 11 Observations of a Remarkable Glazing Phenomenon on the Lunar Surface.
T. Gold. Science. New Series, Vol. 165, No. 3900 (Sep. 26, 1969), pp. 1345-1349. 10.1126/science.165.3900.1345
http://science.sciencemag.org/content/165/3900/1345 [sciencemag.org]
Melted glass from a cosmic impact 12,900 years ago
Ted E. Bunch, et al. Proceedings of the National Academy of Sciences Jul 2012, 109 (28) E1903-E1912; DOI: 10.1073/pnas.1204453109
https://www.pnas.org/content/109/28/E1903 [pnas.org]
Strange that the title of the second paper is different in the "citation tools".
(Score: 2) by PiMuNu on Friday March 29 2019, @01:22PM (2 children)
> A layer of similar glassy substance is found all over earth and has dated to the younger dryas.
I could not read the first article.
The second article is consistent with meteor impacts rather than solar flares (i.e. a big f--ing asteroid).
Or did I read wrong?
(Score: 0) by Anonymous Coward on Friday March 29 2019, @01:29PM (1 child)
When you read scientific literature you need to separate the facts with the explanation. A meteor made more sense to them because they are unaware of the glass on the moon dated to the same period (they don't mention it). It is unlikely an impact would cause both at the same time.
Also paste the dog into scihub to read the moon paper.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @01:32PM
Autocorrect changed doi to dog:
http://sci-hub.tw/10.1126/science.165.3900.1345 [sci-hub.tw]
(Score: 4, Insightful) by Immerman on Friday March 29 2019, @05:56PM (14 children)
From TF summary:
EMPs occur for a variety of natural and man-made reasons including, most notably, Nuclear Explosions and Coronal Mass Ejections (CMEs)
Glass in craters doesn't support anything - you *expect* to find glass in craters. And every where nearby (including all over nearby astronomical bodies, if the impact is large enough) - it's created by the heat of impact, and thrown up in the resulting debris cloud. If the glass was created by a CME, you should see less glass in the craters than on the surrounding surface, as craters will be exposed for a shorter duration than flatlands. You'd also expect to only find such glass on the half ofg the moon that was facing the sun at the time, unless the CME was so sustained that the moon was immersed in it for a full month-long rotation. Might be worth investigating once we've gathered samples from the rest of the surface, but it seems implausible from what little I know of solar physics. CMEs form when a loop of plasma breaks free from the suns magnetic field - they can be quite large, but the "explosion" itself is over fairly quickly after it begins. I suppose a large cluster of separate CMEs would do the job, but I don't think that's likely - especially since the sun rotates roughly once every 24 days, so you'd need constant CMEs constantly erupting all around the equator for a month to hit the moon for that long. A terrifying prospect.
Glass scattered all over the Earth is far more likely the result of a large impact (or atmospheric detonation) than a CME - for it to be due to a CME that ejection would have to spend at least a day passing the Earth (which isn't completely impossible), and deliver an *astounding* amount of instantaneous power to the surface, which is also not impossible, but would be likely very difficult to achieve without superheating the atmosphere to the point of killing most living things. You'd also expect to see a much higher density of glass near the poles, as the Earth's magnetic field would concentrate the worst of the influx there.
(Score: 2, Informative) by All Your Lawn Are Belong To Us on Friday March 29 2019, @06:31PM (5 children)
Maybe, except the part about, "only find such glass on the half of the moon that was facing the sun all the time." There is no part of the Moon that doesn't face the sun for (roughly) 13.66 out of every 27.32 days. "Roughly" because of both libration effect and it's an average not an absolute period. There's only the half of the Moon we never see because the same face always shows towards the Earth; when it is "new moon" the face we can't see (far side) is 100% lit in the Sun and we see only a dark moon and when it is "full moon" we see our facing half all lit up and the far side is dark Better explanation [phys.org] You may have been trying to explain something else but couldn't get past what you said about both a half facing the sun all the time and the 'month-long rotation' which is actually 13 and a half days leading to nearside and 13 and a half days leading to farside illumination.
This sig for rent.
(Score: 5, Informative) by Immerman on Friday March 29 2019, @07:47PM (4 children)
>There is no part of the Moon that doesn't face the sun...
Certainly. Though libration has a fairly minimal effect, and a lunar day (aka lunar month) actually lasts 29.53 Earth days. 27.32 days is the time it takes for it to complete a complete rotation with respect to the stars, but it also travels roughly 1/12th of the way around the sun in the same time period, so it has to make a further 1/12 of a rotation before the sun is back to the same place in its sky.
My point was that a CME impact is typically a brief event lasting only a few hours between when the the first and last particles hit - and that's out at Earth orbit, after the particles have been spread out by 1-3 days of traveling towards us at different speeds. The moon doesn't rotate much in that time (only about 1.5 degrees), so the CME would only hit the side currently facing the sun.
To hit all parts of the surface for even a few moments the CME impact would need to last almost 15 days, and then the impact would be very uneven, in a very distinctive pattern: the strip of the moon at the dawn-line when the leading edge hit (and just reaching nightfall when it was over) would have been bombarded for 15 straight days, while the strip that only caught the leading edge at nightfall, and then the tail end at dawn only gets a few minutes. To get a uniform effect the impact would have to last for a full 29.5 days, so that all parts of the moon were exposed to an equal amount of it.
I'm not sure it's even physically possible for a CME impact to last for even two weeks - that would imply that the "explosion" was an ongoing event that had lasted roughly that long on the sun. Plus, since the sun spins once every 27 days, in order for that miraculously sustained stream of plasma to stay focused on us, the eruption would have to travel more than half way around the sun's surface in near-perfect synchronization with the Earth while it was happening, otherwise the "impact" would be spread around 1/2 of the Earth's orbit, and we'd pass only be hit by a tiny portion of it as it swept across us like a lighthouse.
(Score: 2) by All Your Lawn Are Belong To Us on Friday March 29 2019, @08:57PM (3 children)
Gotcha. Thanks for the clarification. I'd read the parents above you and couldn't quite put it all together... Could it not be a series of CME's (or, far more possible, impacts) over hundreds of thousands of years? (Not one event but many taking place all around the rotative phases?) Or a roast on one side and then a million years later a roast on the other? One might not get uniformity but rather a coat all over? I'm not saying I buy that at all, just exploring the possibility.
The other thing I wouldn't get is why wouldn't it be the volcanic action (if one accepts the impactor-volcanic theory) which created the glass - not just impacts alone. But the timing would be all wrong to glass over just the last 30,000 years as that era was done in the millions of years ago IIRC.
This sig for rent.
(Score: 2) by Immerman on Friday March 29 2019, @09:12PM (2 children)
Sure, lots of bursts are possible.
My biggest objection is with the idea that glass inside craters is evidence of solar activity, when craters would be the least impacted areas by a solar event. Unless perhaps they're talking about glass that was buried by dust and then later exposed when new craters were formed.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @11:23PM
They say "For radiative heating from a small angular source in the sky the bottoms of craters are substantially favored." You are ignoring geometry (it gets warmer in a crater for the same reason it is colder at poles than the equator).
(Score: 2) by All Your Lawn Are Belong To Us on Friday March 29 2019, @11:29PM
True, and as you mentioned there would be unevenness due to crater shadow.
This sig for rent.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @07:10PM (7 children)
You realize you are disagreeing with NASA who concluded it was some sort of solar event... despite admitting you know little about it? I provided the source above, take a look.
(Score: 2) by Immerman on Friday March 29 2019, @08:04PM (6 children)
I don't think the sources post was there yet when I first replied. Not that a one-sentance summary of a media article necessarily reflects what the scientists actually said... but it's a start. And Science was (is? it's been a while) generally one of the better ones.
But regardless, *nobody* understood solar physics all that well in 1969 - we had almost no data about the sun, had only just achieved simple laboratory fusion twenty years earlier, and had no computers capable of running any but the most rudimentary of simulations.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @08:22PM (4 children)
1) Who said this phenomenon covers the entire moon? Have samples been taken from opposite sides?
2) If it is cyclic, then over time the entire surface of the moon would be hit. The period would need to be 15k years or less or micro meteorites would have destroyed these structures (according to the paper). About 15k years before the younger dryas was the last glacial maximum https://en.m.wikipedia.org/wiki/Last_Glacial_Maximum. [wikipedia.org]
3) In the paper they say the sun would have gotten 100x brighter for tens of seconds every few tens of thousand of years.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @08:53PM (1 child)
Well, I'd originally dated Anunnaki first contact to about the Middle Uruk period (3800 - 3400 BCE). But it could have been earlier. This isn't Star Trek, so we have to think about how difficult it would be for a technological civilization to detect signs of a primitive technological civilization after arriving at a strange new planet.
I'd always assumed that FTL travel isn't possible (probably 0.01c tops, even for sufficiently advanced technology), but could about 5 to 10 colony ships dropping out of warp generate an EMP to create glass like that?
(Score: 0) by Anonymous Coward on Friday March 29 2019, @09:04PM
And why do you think this hypothesis is worth considering? Does it predict anything different than the solar micronova one?
(Score: 2) by Immerman on Friday March 29 2019, @09:08PM (1 child)
1) Yeah, I think I fixated on "all the craters" to a ridiculous extent
2) agreed
3) Must be the pay-walled first paper, the PNAS one seems to be focused entirely on meteor impacts and airbursts.
(Score: 0) by Anonymous Coward on Friday March 29 2019, @10:12PM
The download link is here: https://soylentnews.org/comments.pl?noupdate=1&sid=30805&page=1&cid=821781#commentwrap [soylentnews.org]
(Score: 0) by Anonymous Coward on Friday March 29 2019, @08:49PM
It looks like the landing sites are all on the same side.
https://www.skyandtelescope.com/observing/how-to-see-all-six-apollo-moon-landing-sites/ [skyandtelescope.com]