Wikipedia:Reference desk/Archives/Science/2016 January 10

= January 10 =

Does an atomic explosion send EM waves radiation into outer space?
Does an atomic explosion send EM waves radiation into outer space? Would it reach other planets? --Denidi (talk) 03:26, 10 January 2016 (UTC)


 * By "EM wave" do you mean Electromagnetic radiation? If so, then yes and yes. The same could be said for radio stations, your cell phone, the light bulbs on your front porch, etc. etc. Shock Brigade Harvester Boris (talk) 03:38, 10 January 2016 (UTC)


 * My cell phone is sending EM radiation into outer space? --Denidi (talk) 03:43, 10 January 2016 (UTC)


 * Yes. The amplitude is of course quite small. Shock Brigade Harvester Boris (talk) 03:45, 10 January 2016 (UTC)


 * Important caveat: not all transmissions will be powerful enough to escape Earth's ionosphere/magnetosphere.  S n o w  let's rap 03:50, 10 January 2016 (UTC)


 * That's my point. Otherwise why would E.T. the Extra-Terrestrial have bothered building a makeshift communicator to phone home? A cell phone would have been enough.--Denidi (talk) 03:53, 10 January 2016 (UTC)


 * Have you ever had trouble getting a cell phone signal? There's a reason deep space communications use high-gain antennas. You can't fight the inverse-square law. --71.119.131.184 (talk) 04:02, 10 January 2016 (UTC)


 * Well, bear in mind that cellphones didn't exist when ET visited, and also that there is a difference between whether some amount of the radiation escapes the earth's immediate environs and whether a recoverable signal does. And even if the signal escapes intact, depending on it's exact nature, it may be formatted in such a way that it comes across as indecipherable at the other end.  Still, you might want to watch what you say, just in case you do unwittingly become our first envoy to a network of super-advanced alien civilations. :)  S n o w  let's rap 04:09, 10 January 2016 (UTC)


 * Maybe not cellphones in the shape we think of now, but wireless telephones are not new - they've been around for about a century. ←Baseball Bugs What's up, Doc? carrots→ 04:23, 10 January 2016 (UTC)


 * That's true, but I'm not sure I see the relevance. I mentioned the detail of the timing of cellphones because they were the technology referenced.  S n o w  let's rap 04:32, 10 January 2016 (UTC)


 * What do you consider to be the distinction between cellphones and wireless phones? ←Baseball Bugs What's up, Doc? carrots→ 04:34, 10 January 2016 (UTC)


 * A cell tower, a cell network, different transmitter technology, carrier-frequencies, and signal formats. A wireless phone shares about as much in common with a cellphone as a telecommunications device as either does with a walkie-talkie, really.  But I guess I must still be missing your point, because I still don't understand the role you're implying for wireless phones with regard to the OP's question.   S n o w  let's rap 05:09, 10 January 2016 (UTC)


 * The first cellular phone network started operation in Japan in 1979. E.T. the Extra-Terrestrial was released in 1982. It is true that North America, where the film is set, did not have a network in commercial operation until 1983, but hey, E.T.'s from a technologically-superior civilization, so maybe he's an early adopter! --71.119.131.184 (talk) 04:55, 10 January 2016 (UTC)


 * I stand corrected! I wondered if there were perhaps prototype networks before then; I suppose I ought to have reckoned on a Japanese precursor before '82. (and in any event, should have checked!)  S n o w  let's rap 05:09, 10 January 2016 (UTC)


 * Let's try to bring this space Q back down to Earth: Would a nuclear explosion on or near the surface of the Earth create enough of an EMP to damage circuits of spaceships ? StuRat (talk) 04:51, 10 January 2016 (UTC)


 * Good idea, Stu. First, though, I'm going to discuss the main issue involved in general terms so the OP "gets" the answer.


 * Gamma rays are electromagnetic (EM) radiation. They are part of the "prompt radiation" emitted by nuclear weapons immediately on detonation. They are the important component triggering the Electromagnetic Pulse phenomenon, regardless of whether it occurs at or near the Earth's surface or over the ionosphere. This is the EMP phenomenon which grabs headlines for its potential to (according to some commentators) reverse-bias and destroy semiconductor junctions - hence, all manner of integrated circuits in cell phones, the computer you're reading this on, TVs and radios, and the computers and silicon-controlled rectifiers in all modern automobiles.


 * Now, the [STARFISH PRIME] nuclear weapons test, a 1.4 megaton detonation, 250 miles over a point near its launch site, Johnston Island in the Pacific Ocean, may have disabled three satellites in low Earth orbit.  Nuclear detonations at or near Earth's surface, however, would have EMP that propagated much closer to the Earth's surface - not into space.  OP, please read our article Electromagnetic Pulse to understand the issue more fully. loupgarous (talk) 05:16, 10 January 2016 (UTC)


 * (EC) Well I'm not sure how that question brings the issue "down to earth" (in either a literal or metaphorical fashion), but the answer is that it would depend on the scale of the explosion and the particulars of the shielding on the hypothetical craft, as well as the nature of the circuitry. It would have to be a sizable explosion in order to exit the stratosphere, but existing armaments could accomplish it, under the right circumstances. (Edit: forgot that Stu specified a detonation on the surface of the planet. Not quite positive of this statement in light of that hypothetical).  I'm sure if you dig about, you will find the ISS, by way of example, must have emergency protocols in event of a nuclear event. I'd bet money on that, but I'm short on time and can't search out the details just now; hopefully someone else can confirm or contradict that assumption.  Certainly many militaries have invested in heavily shielded aircraft; it's really not that difficult an issue to address (although, again, everything is relative tot he strength of the blast).  S n o w  let's rap 05:25, 10 January 2016 (UTC)


 * Well, it was a factually-based explanation. I don't see anything in your response to show how even a megaton-range detonation at or near the Earth's surface could impact a spacecraft (and in that description I include satellites).  The Russian  Tsar Bomba 50 Megaton weapons test is not recorded to have harmed any satellites.  Neither has any other nuclear weapons test outside the  STARFISH PRIME shot - certainly no nuclear weapons tests inside the troposphere.  Of course, if you have hard data, not speculation or hand-waving showing otherwise, we'd be grateful to you for throwing light on the question. loupgarous (talk) 05:49, 10 January 2016 (UTC)


 * Uh, I think you may want to re-read my post, because nothing in it was intended to challenge anything you said. Point in fact, I wrote my post without seeing yours (EC="edit conflict") and my post is clearly threaded in response to Stu's inquiry, not your answer.  I find your post makes complete sense.  As to the "surface" issue, you will note that I already realized that I had misremembered that detail of Stu's hypothetical and struck/corrected my post accordingly. I don't think you and I are saying anything that is at all inconsistent.  S n o w  let's rap 06:01, 10 January 2016 (UTC)


 * Whoops. Sorry, and you're right.  Stu's point was well-taken, though, the discussion had wandered off for about 30 lines or so about cellphones and everything but what the OP asked about.  Stu brought the discussion back to that.


 * While I regret the misunderstanding on my part, may I offer some constructive advice? It's important to focus on what the OP asked.  Your additional points are actually interesting.  According to this explanation simple solar flare activity is enough of a challenge to satellite designers to encourage them to build in a certain amount of protection against electromagnetic pulse.  Part of that is shielding against electromagnetic pulse, and our article on  radiation hardening technology explains what is done along those lines. loupgarous (talk) 06:32, 10 January 2016 (UTC)


 * I actually view it as broadly important to avoid protracted digressions on the ref desks, to source or wikilink any assertions, to avoid speculation, and generally be as consistent with WP:NOTAFORUM as we would for any other space on the project--or, at the very least, to do so with to the extent that the unique role of the ref desks allows. I think I actually have a reputation as a bit of a hard nose in regard to those positions.  So can you be specific about where you think my comments have strayed off topic?  The cell phone example was raised by Boris, embraced as a line of discussion by the OP and then questioned by Bugs; each of my comments in that line of discussion was a caveat to what someone else had said or an answer to a direct inquiry.


 * As to Stu's question, I personally felt it was a bit of separate issue, since the OP just wanted to know whether the radiation could be detected in space, not what practical effects it would have on technology. Nevertheless, since Stu's question was a reasonable one in its own right, I just decided to treat it like I would any question that was asked in its own thread and supplied what information I could on the topic.  I honestly feel I've been as on-topic as any contributor in this thread, but if you feel otherwise I (genuinely and non-passively-aggressively) will take any observations under advisement.  The gist of my responses to the OP were meant to clarify that not all radiation escapes back out into space (not immediately, anyway), and the gist of my response to Stu was that we could only answer his question in broad strokes without having specific details for both the blast and the materials involved.  S n o w  let's rap 09:09, 10 January 2016 (UTC)


 * The problem with Stu's point is they seem to be making an assumption the OP meant EMP. The OP never said anything about EMP and although the mobile phone discussion may have gotten a little offtopic (particularly the part about whether or not they existed during ET and the distinction between wireless phones and cell phones), it started off from the OP's followup. It's easily possible (actually I think more likely) the OP doesn't care about EMP or potential damage to space ships and is most interested in whether a sufficiently advanced civilisation would be able to detect when someone has worked out how to do generate such explosions from a distance. (This is a common trend in science fiction.) Or maybe the OP isn't even thinking of others looking for such explosions particular, but making the assumption that a nuclear explosion is the most likely "unintentional transmission" to be detected (which I don't think is correct). Ultimately we won't know unless the OP clarifies, but there's nor eason to assume the OP is particularly interested in EMP or damaged caused to space ships or stuff on other planets by nuclear explosions. Sturat may be interested in whether nuclear weapons on a planet may damage spaceships and there's nothing wrong with asking about it for personal knowledge, but such a question isn't inherently more on topic to the OP's question than whether or not ET could have used cell phones to communicate. Nil Einne (talk) 09:36, 10 January 2016 (UTC)


 * The problem with the original formulation of the Q was that it allowed for trivial responses. After all, a candle outside may well cause some photons to leave the Earth's atmosphere, but that's of no significance and thus a trivial answer.  I was trying to find a way to quantify the amount of radiation in a way that might be significant to the OP and not allow for such trivial answers.  Looking at how much radiation it would take for an alien to detect it is also impossible to answer, as it would depend on if that alien is in orbit, on the Moon, on Mars, at Alpha Centauri, or in another galaxy, as well as what size detector he might have.  StuRat (talk) 04:07, 11 January 2016 (UTC)
 * Indeed - but unless you know how, where and when the detection of these EM waves is being made, you can't provide a meaningful answer. If your concern is indeed with satellites being damaged - then that's very different from asking whether hypothetical alien beings orbiting a star 100 light years away would be able to detect them and thereby deduce that there is a population of somewhat intelligent beings with a strong tribal loyalty living on this planet who are intent on each other's destruction.  It also matters whether the detector is looking in one direction or all directions - whether it's sensitive to visible light, IR, UV, radio, microwaves, etc.  Obviously the sensitivity of the detector matters...so does the time of day on earth when it happened - because there would be better contrast at night - and because if the explosion happens on the limb of the earth (as seen from the detector), the signal will have to pass though a heck of a lot of atmosphere versus one that happens in the center of the disk as seen from the detector.  These are not small considerations when answering a question like this.  But if the question is whether any EM radiation at all leaves the earth - then the answer is obviously "Yes" and that answer would also be true of a candle flame or a cellphone call...that's a true answer - but it's probably not of much use...probably.  It is very often the case that our questioners need to hang around to clarify their question in light of what we're able to tell them...sadly, that doesn't happen often enough! SteveBaker (talk) 14:14, 11 January 2016 (UTC)


 * I take the question as meaning could aliens on a planet around another star detect an atomic explosion on earth? Well the signal would certainly be strong enough - but compared to the sun I think it would count as noise whereas a television signal though much weaker could be distinguished fairly easily if they had a huge receiver. But then again if they had receivers spread apart in space they might be able to separate the earth and the sun by direction and so see the signal came from the earth rather than the sun. Dmcq (talk) 11:56, 10 January 2016 (UTC)


 * I think people need a kick here. What we're looking for is a profile of the energy emitted as a function of frequency and time.  I came up with this as an example of what I want - it's pretty deficient in most regards but light years ahead of some of some of the bickering above.  I know some folks here have a better impression of what a number like "100 KV/m" means relative to the local radio station, so please, give the rest of us some help. Wnt (talk) 13:39, 10 January 2016 (UTC)


 * Several people have mentioned specific tests (Tsar Bomba being the largest) - but one should bear in mind that these ground-based experiments were done back in the 1960's when there were very few satellites up there. Subsequent testing went underground, specifically to avoid the effects of the explosion being felt too severely above-ground.  So the odds of one of that small number of satellites being damaged or disabled would be tiny even if there were some EMP or other effect involved.  These days, space is crammed full of satellites - and even if the odds were relatively small, we might see some effect that was not noticed in the 1960's.


 * So I think we need to consider theoretical issues rather than anything that was measured at the time.


 * That said - the reports from Tsar Bomba said that the mushroom cloud went up to 64km high and the heat pulse was felt at ground level 270 km away - window panes were broken 900 km away. Well, the "edge of space" is generally considered to be 100km vertically upwards - so it seems very likely that a low earth orbit satellite that happened to be passing overhead at the time would feel a significant effect...but one in a geostationary orbit would not.


 * Whether an observer on (say) a nearby star would be able to detect the increased EM radiation depends on the sensitivity of their instruments and where the earth was with respect to the sun at the time. If they were unable to resolve the sun and the earth as separate points - then even the Tsar Bomba would be the tiniest blip compared to a solar flare.  But if they had sufficient magnification to separate out Earth and Sun, and if the bomb went off on the side of the earth facing them - then I'd expect that an increase in Infrared and the visible spectrum to be noticed.   Reports of a light and heat as intense as the sun from a distance of 270km through the atmosphere suggest that far more than that would penetrate through the clearer and more tenuous atmosphere vertically upwards...even with a simplistic model of the atmosphere where air was as dense as at ground level all the way up to space (100km) and then vacuum would suggest that at the edge of space, the intensity of heat and light would be 2.72 larger than people reported 270km away.  The albedo of the earth is 0.3 so the explosion would produce a spot that would be certainly be at least 30 times brighter than the normal brightness of reflected sunlight.  So I think that with enough magnification, these hypothetical observers would have had a chance at seeing it.
 * But that's a very speculative answer. Everything depends on the sensitivity and magnification of their instruments - and how lucky they'd be about the timing of the explosion relative to earth's orbit and time of day.
 * SteveBaker (talk) 14:52, 10 January 2016 (UTC)


 * The prime question (one which came up during discussions of the "opacity" of the cloud of debris immediately after a nuclear blast when the characteristics of the nuclear propellant charges and the pusher plate for Project Orion spacecraft were being determined) is what the quantum electrodynamic "window" or "windows" of the blast relative to its surroundings was. The answer to that question determines how many photons in what wavelengths leave the vicinity of Earth after a nuclear detonation.  The OP said "other planets" in the original Q, so it's unclear whether he meant "detection by ET intelligence," which we might assume (from lack of evidence after intensive astronomical and radioastronomical surveys of our solar system for any extraterrestrial intelligence in the Solar System) means "intelligence in other solar systems."
 * If that's the case, STARFISH PRIME may have been a "loud shout" which, assuming our "neighbors" many light years away do radio astronomy, may have given them a clue that a technically-active civilization capable both of spaceflight and high-energy weapons is orbiting our sun.  Even  Tsar Bomba could (if the quantum electrodynamics were right) have caused someone's radiotelescope around Tau Ceti to "blip."
 * But the people out there listening have to make a few intuitive leaps before they can confidently conclude that they saw engineering activity and not just a natural phenomenon they hadn't seen before. Remember the "mysterious objects" in Saturn's B-ring?  It wasn't till 2010, after the Cassini fly-by of Saturn, then some analysis of that data, before these admittedly exotic artifacts were revealed to be natural activity analogous to similar - but larger- activity elsewhere in the Milky Way galaxy.
 * The one-shot nature of STARFISH PRIME and  Tsar Bomba may be the best proof any extraterrestrial astronomers have that the Solar System has intelligent, tool-using life around it.  And the radio emissions, not the visible light, say, from  STARFISH PRIME and all the other atmospheric nuclear tests are their most likely "proof" of that. loupgarous (talk) 20:04, 12 January 2016 (UTC)

Benoit - binomial authority for Euphrictus squamosus?
Hi, RD/S folks,

I recently started an article about this beastie. (I'm terrified of even little spiders, so the "It is requested that an image or images be included in this article to improve its quality" tag on the talk page, I kinda hope it won't get fulfilled.)

The critter's genus article includes the text (that I paste with attribution): Originally, the species E.squamosus, a species of this genus, was described as Zophopelma squamosa, a Barychelid, by Benoit, in 1965.

Who is M./Mme. Benoit is in this context? --Shirt58 (talk) 10:01, 10 January 2016 (UTC)


 * Pierre L. G. Benoit. Here is his French WP page Pierre L. G. Benoit.--William Thweatt TalkContribs 10:26, 10 January 2016 (UTC)


 * Thank you, William Thweatt! I obviously did not do my reseach well enough. I do note that as according to Fr:Pierre L. G. Benoit "Pierre L. G. Benoit est un arachnologiste belge, né en 1920 et mort en 1995" but only mentions "Quelques taxons décrits" without any further references. I have JSTOR access, but haven't been able to find an "in memoriam" in any journals for him.
 * Perhaps the citoyens of WP:RD/S could remedy this? --Shirt58 (talk) 10:34, 13 January 2016 (UTC)
 * Maybe something from this short list of Google Scholar results? The Dunlop & Manal paper (Dunlop, Jason A., and Manal Siyam. "Spiders of Sudan: a literature review." Arachnology 16.5 (2014): 161-175.) looks like it might mention Benoit prominently but I don't have access to that one to confirm.--William Thweatt TalkContribs 10:47, 13 January 2016 (UTC)
 * thank you again. That Google scholar search most certainly indicates that Benoit is a notable arachnologist. What I am actually looking for are reliable sources for his date and place of birth and his date and place of death.
 * Please note that *I am not doing this to be deliberately annoying*. But I fully admit this may well in fact be very annoying.
 * --Shirt58 (talk) 12:13, 13 January 2016 (UTC)

Sleeping pill effects
When will sleeping pills start showing their side effects like dizziness and headaches etc... ? If any one takes 2 pills a day when will side effects start showing up ? — Preceding unsigned comment added by 175.101.24.136 (talk • contribs)


 * Our article on side effects is pretty minimal and links to adverse effect - which is presumably what you're interested in here. As that article points out, these effects may only kick in when you start, stop or change dosage - they may occur randomly in some patients and not others - or (as you suggest) after longer term usage.


 * These effects depend on the individual and on the drug in question and depending on what other drugs you are taking - and even on what things you eat (Grapefruit, for example, is notorious for inducing side effects in drugs).


 * So I very much doubt there is a definite period/dosage at which this might happen.


 * It would be easier to make a guess at this amount of time if we knew which specific sleeping pill you were asking about - but to be honest, that would be a violation of our "No Medical Advice" rule and we would not be able to help you. This is a question best asked of your doctor who can look at your specific situation, the drug you're talking about and whatever other drugs or dietary issues you may have.  The wikipedia reference desk is a VERY bad place to get answers to this kind of question.


 * SteveBaker (talk) 14:22, 10 January 2016 (UTC)


 * It depends on whether you're talking about melatonin, antihistamines (like Benadryl or hydroxyzine), antipsychotics with antihistamine activity (like Seroquel or thorazine), drowsy antipsychotics without antihistamine activity (Latuda), benzodiazepines (like ativan), or a Z-drug. Yanping Nora Soong (talk) 23:36, 10 January 2016 (UTC)


 * Even if we knew all that, Steve's right. We'd be ignorant of the OP's medical status, and violating the "no medical advice" rule here AND other legal and moral strictures about the unlicensed practice of medicine.  If any of us were physicians, those persons would ALSO be ethically restricted from offering medical advice to someone not under their care.


 * So the best advice we can give is for the OP to consult the physician who prescribed the medication he's concerned about. Even if this were unprescribed, Over-the-counter medication, the OP's better off reading the precautionary statements on the package of the medication than accepting advice from the Help Desk. loupgarous (talk) 20:30, 12 January 2016 (UTC)