title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"Is our circulatory system one giant loop that involves all blood vessels or is it composed of many smaller loops which don't connect to each other?"
] | [
false
] | null | [
"All blood vessels are connected to each other. This becomes obvious when you realize that all our blood vessels have to connect to our heart, which is the pump for our circulatory system."
] | [
"The circulatory system is actually ",
" separate sets of tubes: one big closed loop (the blood vessels), and a second, open-ended, one-way system (the lymphatic system) that reclaims and conveys any fluid that leaked out of the blood vessels (about 3 liters in a day) back to the heart to rejoin the blood loop.",... | [
"Many smaller loops, but all connected to each other. Really simply: Arteries lead away from the heart, branching off to different parts of the body getting smaller as they get further out. The smallest vessels are capillaries where the blood actually perfuses the tissues. The blood then returns via veins. Initiall... |
[
"Can cravings for specific food be a symptom of deficiency?"
] | [
false
] | [deleted] | [
"There are some deficiencies that seem to have an effect on what we crave, such as low iron, calcium, zinc, and sodium. E.g. we crave meat for the iron, salty foods for the sodium (rare), etc. It appears there is some evidence to support these, but the research shows it is not the case for all (or even most) nutrie... | [
"Not having enough sodium in your diet being rare seems like the understatement of the decade."
] | [
"It's weird how the article is not mentioning sugar when having a low blood sugar level. That's the one I most commonly seem to have."
] |
[
"How fast can germs travel?"
] | [
false
] | Obviously - as small as they are - viruses, bacteria and fungal spores use larger animals as their primary means of transportation. But given a sterile surface, if contaminated in one spot and no other interference, how long before another spot - say 6 inches away - is actually contaminated? | [
"Pretty much only bacteria have a means of traveling on their own. Viruses need a host to move, although sometimes they can infect bacteria and be transported that way. Fungal spores also don't move by themselves, instead spreading based on air or water currents, mostly. Protists, another class of single-celled org... | [
"Is it not also the case that bacterial motion is rather randomized in terms of where they are going?\nI remember from my Microbiology lectures at university that they kind of zigzag around the place, not ever moving in a straight line for very long.\nIf so, the minimum of time for the bacteria to move the given di... | [
"I was just trying to give a theoretical minimum time. Yes, there is a lot of random motion, but bacteria also do follow chemical and other signals with impressive accuracy and purpose. There are cool videos of them and other cells following various trails and signals online."
] |
[
"If we can see light emitted from the big bang, could we hypothetically \"hear\" the big bang at a considerably shorter distance?"
] | [
false
] | I've wondered this for a while. If the observable universe stretches 46 billion light years in every direction (a figure I just took off Wikipedia). Could we, knowing the difference in the speed of light and sound, calculate approximately where the "sound" from the big bang currently is? Thanks! | [
"Actually, the earliest light we can see is from the CMB. The CMB is roughly 380,000 years after the Big Bang. Prior to that, photons did not last long enough to travel any distance.",
"In the Big Bang model for the formation of the universe, Inflationary Cosmology predicts that after about 10−37 seconds[6] the... | [
"WTF is going on here? Space isn't a perfect vacuum, but there are particles - and at higher redshift, more and more. The density of matter scales like (1+z)",
" so space had the density of air at a redshift of about a billion (a lot, but the universe was still ~30 seconds old, so it's after Big Bang Nucleosynt... | [
"The one thing that no one is mentioning is that the Big Bang is not an event that happened at a place, so you can't somehow figure out where it happened. It happened all at once everywhere in the universe, which as far as we can tell is infinite in extent."
] |
[
"From my 7 year old: Do the things in our bodies ever get tired? Like cells and antibodies? Do they have to rest?"
] | [
false
] | null | [
"Excellent question! ",
"Cells themselves don't need to rest in the way that the entire body does, but some organs and body parts do. Cells use a molecule called ATP to make stuff happen. Food + oxygen is turned into ATP and carbon dioxide. When you feel tired, what you are feeling is low amounts of ATP or other ... | [
"The basis of recommended amount of hours per night of sleep an average human should obtain is based from studies, both observational and experimental. Essentially researchers just took a bunch of data and analysed/compared which group functioned better. Some people need more, some less.",
"As for why, there are ... | [
"Can you explain why the brain needs X hours of sleep?"
] |
[
"What’s the reason head lice prefer the head and pubic lice prefer the pubic area? Hair is just hair isn’t it?"
] | [
false
] | null | [
"If you look at a diagram of pubic lice vs head lice you will notice the claws of pubic lice are bigger and more suited to thicker hair. The species is more likely to stick on the host in their respective regions because of this difference but that does not mean there’s zero chance of finding pubic lice in the eyeb... | [
"I hate you for making me learn I could potentially get pubic lice in my eyelashes"
] | [
"The hair spacing of eye lashes serves pubic lice fairly well too.",
"Not seen it yet myself but colleagues in the eye clinic have."
] |
[
"Does rinsing fruits/vegetables with just water really clean them?"
] | [
false
] | So I buy an apple, bring it home, rinse it and rub it a little with my hands, dry it off and then eat it. Does this really take everything off that should worry me? I've heard of a "vegetable wash" for this task.. Is that necessary? | [
"Sort of. It'll get rid of any pesticide residue and dirt on the outside, but it's not the best at removing bacteria. Bacteria aren't all that water soluble in the first place - there's a reason you use soap when washing your hands, and it's not because it smells good. Worse yet, a lot of produce has nooks and cran... | [
"I'm not an expert on exactly which pesticides are used, but when I worked on a farm, all pesticides had half-lives, either from them washing away or degrading. Guys in white suits come through, spray the place down, nobody is allowed in for 48 hours. After that, it's deemed safe, no special washing required.",
"... | [
"Why would farmers use pesticides which wash off when it rains? I assumed that they would be specifically designed to be non-water soluble."
] |
[
"How does scuba gear keep the water pressure from crushing your lungs?"
] | [
false
] | [deleted] | [
"The scuba gear itself doesn't really do that. There are two pressure regulators, one on top of the tank and the second one as a part of the mouth piece. These combine to deliver air from the tank at atmospheric pressure i.e air equal to the \nthe pressure of the water around you.",
"The air in the lungs will a... | [
"To expand on this, the deeper you go scuba diving, the more compressed the air in the tank and in the lungs (and gas in your blood), so the same amount of expansion of lungs in response to a breath will draw in a greater amount of more compressed air. Thus, the deeper you dive, the quicker you consume air. ",
"T... | [
"more compressed the air in the tank and in the lungs",
"Technically the air in the tank isn’t compressed. Since it’s in a rigid container the pressure of the air inside depends only on the volume of the tank, the temperature of the air and how much air there is in the tank. It only really compresses in you body!... |
[
"How do Americans get 115V?"
] | [
false
] | Well obviously from a plug socket, but I digress. In Europe, our power is generated in 3 phase (Red, Blue, Yellow, all 120 degrees apart), and when it's transformed down to its consumer power level, the voltage across any two phases is 400V. When there is a star load, you can take power from a single phase relative to ... | [
"most of us do get 240V to the home, as a single phase- but that phase is \"split\" - the transformer that supplies the house is center-tapped, that center is pinned to ground, so there's effectively a +120 and a -120. obviously not really positive and negative since it's a/c, but they're 180° out of phase. so so... | [
"You sound fairly knowledgeable for power in europe, so I can make this quick.",
"Is it transformed down from 230V at some point? Is the 3-phase voltage different?",
"That is the 3 phase voltage. Utilities will deliver 240V, 3 phase, at the transformer. Once inside a structure, the wiring will center tap result... | [
"Hey, just a heads up- but making comments on askscience which don't contribute to the discussion is frowned upon. A post explaining the rules can be found ",
"here",
", and if you're intent on trolling- I'd suggest just taking it somewhere else, because you'll just get your comments deleted and your account ba... |
[
"Can a camera record different frequencies of light at the same time? For example, can one camera with a single lens record visible light and infrared at the same time?"
] | [
false
] | null | [
"Keep in mind that every color you see is actually a different frequency, so a color image is an example of a picture in more than one frequency. The lens does matter a bit as glass, for example, can make a great lens for optical, but is opaque to infrared, so infrared cameras will have lenses made out of things li... | [
"This bit about the material is interesting! Say you have a glass lens. Is it a gradual transition into opaque as you go toward infrared, or a sharp cut-off/transition? "
] | [
"Yes, they certainly can.",
"I'm solely going to focus on digital cameras in this answer, as they are by far most common today.\nA camera sensor with a Bayer-filter array (red, green and blue micro-filters), captures electromagnetic radiation around the visible spectrum. It can capture near infrared radiation bec... |
[
"Would fireworks look the same on mars?"
] | [
false
] | Would the color be different, the way they look or would they look the same? | [
"They would look the same, the colors you see are the result of a chemical reaction occurring in the materials of the firework itself. Fireworks include their own oxidant, so they would burn the same on Mars as they would on Earth or even in space.",
"When they explode, they would probably spread out farther due... | [
"Yes, the thinner atmosphere would make the report sound muffled.",
"HERE",
" is an approximation of the difference between sound on Earth and Mars."
] | [
"How would the sound be different? Would it just be fainter?"
] |
[
"How do we define the strength of the fundamental forces?"
] | [
false
] | I understand that the force between two objects each with 1 coulomb of charge is stronger than two 1 kilogram objects, but how could we say that the electromagnetic force is stronger than gravity? If we used different units (Like nanocoulombs and megagrams), would we say that gravity is stronger? | [
"The only reason gravity beats EM at large scales is because protons and electrons almost universally balance each other out, making macroscopic things electrically neutral for the most part. If you had a macroscopic ball of protons (somehow), and one of electrons, the force exerted between them would still absolu... | [
"Of course not, since people can, and do, use very different unit systems. ",
"The relative strengths of interactions can be compared fairly well by considering their coupling constants. They are unitless quantities and thus independent of the unit system used.",
"Alternatively, on a more basic level, you can f... | [
"You're exactly right, the relative 'strength' of the forces is not the most fair comparison. These relative strengths are based mainly on their relative forces on an atomic scale. The strong nuclear force dominates here, holding the nucleus together, with electromagnetism not far behind, trying to tear the protons... |
[
"If you see through a colored filter, will the brain eventually adjust and reprocess it normally?"
] | [
false
] | [deleted] | [
"if the filter is broad enough that it lets through light that can stimulate all three types of cones, then you could probably adapt enough to be able to discriminate colors again, but not as well as without the filter; if it's a narrow filter (e.g. that is strongly red or blue), you won't be able to see color norm... | [
"Such a phenomenon definitely exists, and is called ",
"chromatic adaptation",
". This process can can be illustrated by the concept of ",
"color balance",
" in photography. The key is that our brain carries out quite a bit of processing when you viewing a scene, one effect of which is to make a scene appea... | [
"Just put on tinted ski goggels for a few hours. The first 5 minutes look a little distorted, but then it all returns to \"normal\". Then after a while, the same happens when taking them back off. "
] |
[
"Do insects have things similar to digitigrade, plantigrade and unguligrade feet?"
] | [
false
] | null | [
"Walking insects generally use tarsi (5 segments) at the end of their legs to contact the ground. Most insects have a specialized 5th segment for grasping that features claws or hooks. There is tons of variation in the insect world though, given the vast number of species compared to other animals. I'm sure some... | [
"There's some modification that I can think of, but it's in insects without true legs, i.e. prolegs or creeping welts."
] | [
"Here's",
" an interesting video talking about how some insects and other animals differ in what parts of the leg are used in locomotion. In particular, it introduces the idea of the \"distributed foot\" comprised by, for example, the spines on cockroach legs - structures that amplify the contact between the inse... |
[
"Does the gravity of the outer planets., viz Gas giants and Ice giants, influence the positioning of earth? What would have happened to the structure of solar system if the Outer planets where not there initially."
] | [
false
] | null | [
"As others have posted the gravitational effects of the outer planets on Earth are dwarfed by the sun's effects, but the Outer Planets are important in fact that they are so massive they suck in many large objects passing through the Solar System that could hit Earth and disrupted the formation or continuance of li... | [
"The gravitational influence of other planets is dwarfed by that of the sun. If the outer planets were not there, Earth's orbit would probably be slightly changed, but not noticeably. "
] | [
"F = GmM / r",
"G = gravitational constant (6.67384×10",
" m",
" kg",
" s",
"m = mass of Earth (5.9736×10",
" kg)",
"M = mass of Jupiter (largest of the outer worlds) (1.8986×10",
" kg)",
"r = distance (closest is 5.88e9 m, force will be lower as distance increases)",
"Force = 2.189e22 N",
"wh... |
[
"What is the science between wine reduction?"
] | [
false
] | [deleted] | [
"It simply evaporates. The goal is to concentrate the compounds that lend wine (or whatever you're reducing) its flavour by reducing the total volume, creating a very tasty broth. Reduction here does not refer to reduction in the chemical sense of reduction/oxidation reactions."
] | [
"A few other details that aren't totally off topic.",
"First, unless the reduction is carried to completion (meaning that the liquid is entirely evaporated), there will be some alcohol left. It will be less than before, but the common assumption that the alcohol boils off first is incorrect.",
"Second, the alco... | [
"Hmmm I wish it did! How disappointing."
] |
[
"How did people do spacewalks from these small crew capsules without losing their air?"
] | [
false
] | At the time where people started to go to space they made these small spacewalks from the crew capsules but how did they do that? I think they needed some kind of airlock so they don't lose their air but how does an airlock fit inside these small capsules? Or did they just had a tank of air to fill the vacuum after the... | [
"There was two main ways. The first spacewalk by Alexei Leonov was done using an inflatable airlock. It looked like a tube that inflated from the side of the spacecraft. You can see it ",
"here on a painting by the man himself",
".",
"The American early spacewalk were done from the Gemini spacecraft. In that ... | [
"You can get pretty sturdy/stiff inflatable structures if they are designed correctly. Leonov had huge issues with suit pressure that made his suit balloon up and very hard to bend. It made it hard to get back into the tiny airlock. The first spacewalk nearly ended in a catastrophe and he had to vent his suit to qu... | [
"The risk of failure is debatable. The inflatable modules are something like 30cm thick once inflated, consisting of many layers of Kevlar, ballistic nylon, and other materials. It’s basically built up like a really thick ballistic vest. In earth based testing, it survived hyper velocity impacts much better than th... |
[
"Is it possible to graph 4 variables on one graph?"
] | [
false
] | On a 2d graph, you can graph 2 variables and you get a line. On a 3d graph, you can graph 3 variables and you get a surface. Is it possible with a "4d" graph, you can graph 4 variables and get some other visualization? This may be stupid, but it just popped into my head. | [
"One nice way of graphing an additional degree of freedom is to use a colour scale and colour your graph according to the value of that last variable. I used this a lot in my dissertation by graphing 3D plots (a surface) without actually rendering anything in 3D, just by using a top-down flat view of a coloured ima... | [
"I have a bunch like ",
"these",
". They're pixelated but that doesn't really change the concept.",
"I also have some like ",
"these",
", which used to be in the form of the above (just not pixelated), which I turned into contour plots because I felt they looked better in print, but I kept the colour scal... | [
"Can you post a picture example of one of your graphs, just to give us a better idea of what you mean?"
] |
[
"What could be beyond the outermost galaxies?"
] | [
false
] | null | [
"There's no way to make it intuitively sensible without resorting to math, I think. However, there are an awful lot of people on askscience who are smarter than I, and perhaps someone will make a better 3D analogy."
] | [
"There's no way to make it intuitively sensible without resorting to math, I think. However, there are an awful lot of people on askscience who are smarter than I, and perhaps someone will make a better 3D analogy."
] | [
"The idea of a finite but boundless universe was presented by Hawking in A Brief History of Time. In his example he compared the expanding universe to the surface of an inflating balloon. \"Up\", in that case, is the arrow of time. However, this model requires curved space. Since that book was written there have be... |
[
"Why do electrons and protons have exactly the same charge magnitude even though their masses are different by a factor of nearly 1,000?"
] | [
false
] | null | [
"I guess I asked the question badly. My question seemed to imply that mass and charge are related.",
"What I'm saying is, I can understand that the masses of two different particles would be completely different, as there doesn't seem to be any reason for them to be the same. ",
"So why should a property like c... | [
"\"why is charge quantized?\" I'm sure you'll get plenty of interesting reading, with an ultimate answer of \"nobody knows.\"",
"Actually, there is a really interesting answer. At least more interesting than that. If there were magnetic monopoles, ie. a \"magnetic charge\", then not only would the Maxwell equati... | [
"\"why is charge quantized?\" I'm sure you'll get plenty of interesting reading, with an ultimate answer of \"nobody knows.\"",
"Actually, there is a really interesting answer. At least more interesting than that. If there were magnetic monopoles, ie. a \"magnetic charge\", then not only would the Maxwell equati... |
[
"Why does taking a hot shower temporarily relieve the symptoms of many minor human illnesses?"
] | [
false
] | Colds, the flu, a nasty sore throat, a cough, a hangover: a hot shower seems to take away the pain, soreness, exhaustion and general discomfort for at least a while. I understand the medical reasons why a hot shower might help soothe a cough, just like a humidifier, but what's the effect it has on the rest of the body?... | [
"The short answer would be vasodilation provided by heat. That would increase blood flow to affected areas and reduce pain and soreness and general discomfort. As far as a hot shower alleviating exhaustion, I don't know the precise mechanism behind that. ",
"There may also be a degree of psychology (placebo effec... | [
"That doesn't really hold up as if you have a hot shower you will sweat more to reduce your body temperature however this will have no effect due to the high humidity and constant exposure to the hot water. You also don't absorb water through your lungs. ",
"One thing that does occur is any mucus in your lungs an... | [
"Another thing that contributes to some extent is the hydrating effect of being exposed to that much water vapor, since a pretty good amount of that will be breathed in."
] |
[
"Trampolines in low gravity"
] | [
false
] | If all other things are equal, would a trampoline jumper achieve a different height in lower gravity? I.e a Moon base with full atmospheric pressure and a very high ceiling vs a similar setup on Earth. | [
"The trampoline is just a spring and just returns any energy put into it. So the question is really, \"Can people jump higher when there is lower gravity?\" The answer is definitely yes. With less gravity, the gravitational acceleration is lower. That means with a given initial velocity upwards, it takes longer to ... | [
"You will jump higher because the velocity of a projectile follows a parabolic function. If you jump up at two meters per second gravity will decelerate you to zero, then it will reaccelerate you to two meters per second exactly when you hit the trampoline. In this aspect, it is completely unimportant what the mag... | [
"You are assuming that he would bounce around like an inanimate object, a human however is using the leg muscles when jumping, so given the right timing the jump will be pretty high, also any follow up jumps would be just as and higher as you will keep using your legs"
] |
[
"Why do red and purple look similar when they’re at opposite ends of the spectrum?"
] | [
false
] | null | [
"Purple is a non-spectral colour, being a mix of red and blue. Violet is the name for the pure spectral colour beyond blue, and the reason it looks slightly red is that red cones have a small secondary peak of sensitivity at around that wavelength:",
"https://midimagic.sgc-hosting.com/huvision.htm"
] | [
"Your perception of color is related to the wavelengths of various visible light, but it's not a linear scale, the information is translated into color to emphasize important distinctions you might see in the world, rather than give you a precise accounting of wavelengths.",
"Somewhat separately - violet and pur... | [
"Perhaps a more informative way to phrase the original question would be \"Why is pure violet perceived as similar in color to a mixture that includes red?\". I found an explanation at ",
"https://web.archive.org/web/20170226011606/http://gene.bio.jhu.edu/violet/violet.html",
"."
] |
[
"Is time the same on Mars?"
] | [
false
] | [deleted] | [
"If you're talking about relativistic effects, they are effectively negligible. We're talking less than a part per million difference. In terms of timekeeping, the conventions on Mars are different because the days aren't 24 hours."
] | [
"the day on mars is roughly 24 hours and 40 minutes. i think a human would have little problem adjusting to that cycle. other than that i don't know what factors would effect human behavior differently to how they would on earth.\n",
"http://en.wikipedia.org/wiki/Mars"
] | [
"The engineers at NASA working with Curiosity are on a Martian sleep cycle."
] |
[
"What happens when sound waves outside the human ear's range make contact with us? And why don't we perceive them?"
] | [
false
] | null | [
"Bear in mind that we often still perceive such soundwaves, but just not as sound (e.g., the feeling of really deep bass at a concert).",
"Incoming sounds produce a traveling wave which propagates down the basilar membrane (to which the hair cells are attached, which in turn traduce motion into electrical dischar... | [
"There are tiny hairs in your cochlea ",
"I think it's important to note that these aren't actually hairs, but are actually stereocillia. They are commonly referred to as \"hair cells\", but are orders of magnitude smaller than the hairs on your head.",
"Those sounds outside of our range of hearing produce less... | [
"I think it's also important to mention that is seems that the human auditory cortex has evolved to interpret human speech, so those are the frequencies to which the Basilar Membrane is most responsive. We have hair cells beyond the range of speech frequencies to give us environmental cues, but the natural resonanc... |
[
"My 5 year old asked me \"daddy, how does a medicine know where to go once it gets to the stomach?\" after watching me take a pill for a headache. That got ME thinking and now I'm curious cause we always take it so normal on the everyday life."
] | [
false
] | [deleted] | [
"Medicine doesn't \"know\" where to go (at least, not yet). Ingested chemicals are dissolved in the body and reach areas they are able to go. In your case, a pain-reliever (like an NSAID) dissolved in your stomach, was absorbed into your blood stream, was distributed across the systems in your body, including cro... | [
"The field of working out how to make drugs go to a specific place is called ",
"targeted drug delivery",
" and is a very active field of current research, especially for new cancer therapies. There are a variety of methods under study for doing this, which are pretty well summarized by the Wikipedia article. ... | [
"There are already examples of this just entering common use now ",
"http://en.wikipedia.org/wiki/Antibody-drug_conjugate",
"In this case, the antibody provides the targeting for a general poison."
] |
[
"Why do we seem to discover periodic table elements only in sequence of the number of protons in the nucleus?"
] | [
false
] | [deleted] | [
"Couple of reasons. The main one is that the reaction cross section (probability of creating) for making these super heavies falls very quickly the larger the nuclei. So we simply have not done enough measurements to even see the much larger ones. In addition, the target and beam are chosen to yield a specific o... | [
"Anywhere I can read about that last thing?"
] | [
"I would have to search for the papers. Those type of experiments were mostly done in the 60s and 70s"
] |
[
"Is it possible to have a completely clean eye in a cyclone?"
] | [
false
] | The fantastical artic hypercane in the movie "The Day After Tomorrow" are shown with a completely clean eye that allows a clear and quite spectacular view of the surrounding eyewall. Now is this actually possible in reality, can real life tropical cyclones present a completely clean eye? I ask this because in all the v... | [
"I hesitate to even answer this question based on how horrifically unrealistic the science is in that movie. So in case anyone unfamiliar with the movie's \"science\" is reading this, I'll just start by linking to ",
"this brief list of some of the many things wrong with that movie meteorologically",
".",
"Fo... | [
"Wow thank you so much. This was exactly the kind of answer I was looking for. For the movie, I actually have some background in meteorology, and I know how terrible it is in scientific terms, I used it as an example just to visualized my idea of a completely calm eye. ",
"Thank you so much again",
""
] | [
"To get back to you a bit later, today's landfall of Hurricane Michael saw a good portion of the eye cloud-free. Here is one video: ",
"https://www.facebook.com/Stefan1126/videos/10156491591296138/",
" I did not think it would be possible for a storm of this intensity, but you can see almost the entire eyewall ... |
[
"Interesting biology work for a high school student?"
] | [
false
] | null | [
"Find out if there's any colleges nearby that have bio labs. If you ask a professor if you can volunteer in their lab you'll learn a bajillion times more, actually get to do real research, don't have to pay anything, and get something that looks REALLY good on resumes/college apps. Tell your parents helping you get... | [
"Where does it belong?"
] | [
"Not here. This subreddit is for scientific questions, not questions about science related jobs. "
] |
[
"Why do I only seem to get itchy and antsy right before I fall asleep, this causing me to move and become uncomfortable?"
] | [
false
] | null | [
"Hello,",
"We can't speculate about this here."
] | [
"Ok where can we? "
] | [
"You could try ",
"/r/answers",
"."
] |
[
"How do we know what makes up the center of the world?"
] | [
false
] | null | [
"The primary way that the different layers of the earth were discovered was through seismology. An earthquake creates a wave that begins near the Earth's surface and propagates outwards in all directions, all the way across the planet if it's strong enough. With sensitive detectors you can feel earthquakes from all... | [
"This is definitely the correct answer, I just wanted to add on a couple of things (which I’m sure you know, but for the benefit of other readers):",
"The mantle also comes out of the surface every once in a while as lava, so that helps",
"These are known as mantle xenoliths (literally ‘foreign rocks’) and are ... | [
"A fancy way is to actually \"x-ray\" the Earth. A normal x-ray picture works since bones absorb gamma rays differently than muscles/flesh etc. If you want to \"xray\" the earth you will need a particle type that isnt absorbed so easily on the whole distance. So ",
"people use neutrinos for that",
"\nThis kind ... |
[
"Is the Montreal plan to dump sewage into the St-Lawrence river actually that bad for the environment or is opposition to it just people trying to get environmental brownie points?"
] | [
false
] | null | [
"Outside of my field off expertise, but just to get things started, here is an article from 3 days ago where a researcher comments on the whole thing (",
"http://www.lapresse.ca/le-nouvelliste/actualites/environnement/201510/07/01-4907728-deversement-deaux-usees-a-montreal-luqtr-va-etudier-les-effets.php",
") -... | [
"Can't speak to the situation in Montreal, but dumping raw sewage into rivers is a pretty common issue in larger cities with older sewer systems. The sewer lines (sanitary sewer) are where the water goes when you flush your toilet/run your sink/where any water goes down a drain. This water flows to a treatment faci... | [
"So ",
"according to the professors from the Polytechnique engineering school, the dump is no big deal.",
"Its total volume is 0.5% of the river's flow, so the dilution factor alone lets us breathe easier. This means if you released it all in one second, the \"clean\" river would still dwarf the waste. The exp... |
[
"Why do we talk & act like we're drunk when we become exhausted?"
] | [
false
] | As someone who's had plenty of nights drunk & also had work days that seemed to never end (not at the same time)... I've always wondered this. Can anyone explain this to me? EDIT: thank you kindly to those that replied with intent to truly answer my question. Best response (& scariest) so far, by cough_e: When you are... | [
"Although this thread seems to be a downvote magnet, no one has really answered the question.",
"Although there are other factors at play, the main reason your body feels tired is because an increase in the neurotransmitter gamma-Aminobutyric acid, or GABA. This is an inhibitor that blocks the normal excitability... | [
"Please read the ",
"AskScience guidelines",
" before posting. Top level comments are reserved for expert panelists or comments that provide factual evidence with appropriate sources. ",
"Thank you!"
] | [
"/r/askscience",
" is not ",
"/r/funny",
" "
] |
[
"Why do we stop feeling hungry when we're nauseous?"
] | [
false
] | I currently have some sort of stomach bug and I've been having diarrhea all day (TMI, sorry). All I've eaten today is a granola bar (and about half a bottle of powerade) and I don't feel hungry at all. I am just curious what's going on in my body - are the mechanoreceptors in my stomach cells somehow less sensitive? Ar... | [
"Your gut is highly connected with your central nervous system and controlled by the parasympathetic nervous system. My assumption would be that if you feel sick your nervous system will be preoccupied and the same centre that controls appetite (Hypothalamus) will not be responding typically. This in turn will be r... | [
"Well, to answer ",
" we stop feeling hungry, it's an evolutionary trait to try to prevent anything else from entering your system that might cause you harm. If you've recently eaten something that's contaminated (or you're likely to... contaminate your surroundings) it may be best not to want to eat. Things that... | [
"Thanks for the insight! Sounds like that might be a hormonal response, then."
] |
[
"When we're out of oil. Will there still be plastics?"
] | [
false
] | I mean - will there always be some oil to drill up to make plastics, or will we have to move to similar materials? I have for example seen very much looking like plastic material made out of corn starch. Are there alternatives? | [
"Oil will probably never run out in the sense that it becomes impossible to find a single drop left anywhere on earth. Most parts of oil can be ",
"synthesized",
" from coal, gas or even biomass. So oil-based products will simply become gradually more expensive and replaced by alternatives where it is viable. I... | [
"Yep There are tons of different Bioplastics as they are called. some examples incluce... polylactic acid (PLA), Polyhydroxyalkanoates (PHAs). The wikipedia article does a good good of summerizing some of the common ones. If a chemical can be polymerized chances are we can turn it into a plastic for the right pr... | [
"In addition, recycling and extracting oils from waste plastics may be utilized more."
] |
[
"How likely is it that the \"Big Crunch\" is the ultimate fate of the universe? What sort of evidence led to this theory?"
] | [
false
] | null | [
"Given that the Nobel Prize in 2011 was given to the people who made the discovery that the universe is expanding at an accelerating rate, I would say not very likely. \nThe evidence so far suggests that the universe is expanding, and as it expands more dark energy is created. The mechanism that would lead to the b... | [
"So what is the ultimate fate of the universe? Everything will separate from everything else and the universe will expand forever",
"Trying to prevent the spread of this misinformation.",
"This isn't true, the ultimate fate of the universe is not known.",
"Accelerating expansion does not imply A big rip. We r... | [
"Is it just me or does a big crunch sound more optimistic than ever-expanding-into-darkness-and-cold? It'd be an epic end to the universe, maybe spawning another. I don't see how expanding forever is anything but terribly depressing."
] |
[
"Two probably nonsensical questions on spacetime from a layman."
] | [
false
] | Total relativity novice here. I understand that mass somehow "warps" the fabric of spacetime, thus massive objects "experience" time differently. What I am curious about is the underlying reasoning for this. What I am thinking of is that: it is harder to move a mass through physical dimensions of space (i.e. more en... | [
"Spacetime doesn't really care about the difference between space and time. Remember the length contraction and time dilation in special relativity? These arise because different reference frames have different conceptions of which directions are spatial and which is time. Time in my rest frame is going to be some ... | [
"Wow, that's a very good article. Not only that, but most of the articles it links to are clearly written and highly accessible. Physics is so much better on Wikipedia than my field."
] | [
"I meant that more as an apology than a complaint. I really should get back on Wikipedia."
] |
[
"Why do the eyes of some blinded people lack pigmentation?"
] | [
false
] | Is there a reason some eyes appear to be a grayish-blue color when blind? | [
"The lens becomes cloudy and occluded, making it appear white: ",
"http://en.wikipedia.org/wiki/Cataract"
] | [
"You might be thinking of cataracts, which can cause blindness.\n",
"Image"
] | [
"Right, the eyes don't lack pigmentation. Eyes that lack pigmentation such as in ",
"Albinism",
" appear red or purple."
] |
[
"Is it genetically possible for a mutation to occur that would give us superhuman properties? (i.e. something like Spider-man or the X-Men)"
] | [
false
] | null | [
"Well, consider that it was a series of mutations that advanced humans above the fray of primates amongst which we evolved. Compared to modern chimpanzees our powers of speech and problem solving could be considered a super power. ",
"So the possibility of future mutations endowing future humans with new capabili... | [
"This is probably the essential difference between the X-men and actual genetics. In the X-men universe, there's a single mutant gene that enables all of the special powers. In reality, it'd typically take mutations in a large number of genes to give someone a super-human feature."
] | [
"Wolverine actually had bone claws before they were covered with adamantium.",
"http://en.wikipedia.org/wiki/Wolverine_(comics)#Powers_and_abilities"
] |
[
"Are K+ ATP dependent channels active or passive transport?"
] | [
false
] | null | [
"So... what is the definition of active transport again? Rather, what is active transport ",
" on?"
] | [
"Active transport is movement that requires the input of energy. I'm not sure if this involves the input of energy however. The channel is open if there is no ATP bound to it and closes when ATP binds to it. My concept of it is that ATP is acting as an allosteric inhibitor by binding, not by phosphorylating. "
] | [
"Ahh, that does make it more confusing! I would say that it is not active transport because the ATP is not being hydrolyzed for energy. The channel is ",
" by this hydrolysis I'm sure, as being hydrolyzed will turn it back to ADP (much like in a G-protein that is active with ATP and then hydrolyzes it to ADP to b... |
[
"Is there a Bayesian analog to the frequentist chi-square goodness of fit test?"
] | [
false
] | null | [
"Dude this is askscience. Not being elitist or anything but its for people who have specialist knowledge to put forward their opinions on a questions asked, not for people to add 'whimsical' comments. "
] | [
"Dude this is askscience. Not being elitist or anything but its for people who have specialist knowledge to put forward their opinions on a questions asked, not for people to add 'whimsical' comments. "
] | [
"Well the Bayesian point of view is somewhat simpler. You can't just reject a null hypothesis, you instead pick the best, i.e. MAP, hypothesis from a set. So you calculate P(Model|Data) for all models, and pick the best one.",
"Are you looking for Bayesian examples where normal distributions are tested, or where ... |
[
"How do audio books, printed books, and videos differ in terms of how our brains retain and process the information?"
] | [
false
] | [deleted] | [
"I know video and books are definitely different. but paper books and audio books are processed in the mind almost identically. so when you listen to an audio book it is nearly as if not better than reading the book and handled almost identically in the mind.",
"Better with a particularly good reader as they can ... | [
"Learning style typically has no effect on performance, although we believe it does.",
"Here's an article published by one of my colleagues in the British Journal of Psychology ",
"http://onlinelibrary.wiley.com/doi/10.1111/bjop.12214/abstract"
] | [
"Learning style typically has no effect on performance, although we believe it does.",
"Here's an article published by one of my colleagues in the British Journal of Psychology ",
"http://onlinelibrary.wiley.com/doi/10.1111/bjop.12214/abstract"
] |
[
"Could we use photons to create a black hole?"
] | [
false
] | If I understand it correctly photons have a mass. If I put a large convex mirror in front of the Sun could the photons in the focal point create a black hole? And how large would that mirror have to be? | [
"\"Ball-lightning\" is just a name here, not saying that the weather phenomenon is related to black holes."
] | [
"Doesn't ball lightning last for more than a nanosecond? Wouldn't a black hole of such tiny mass evaporate so quickly it'd be nothing more than a burst of energy radiating out? "
] | [
"Doesn't ball lightning last for more than a nanosecond? Wouldn't a black hole of such tiny mass evaporate so quickly it'd be nothing more than a burst of energy radiating out? "
] |
[
"If we sent a probe into space away from earth at the speed of light, would it be able to transmit data back to us?"
] | [
false
] | null | [
"You can't accelerate an object with a non-zero rest-mass to the speed of light as this would violate special relativity. You can, however, accelerate the probe arbitrarily close to the speed, in which case it would still be able to transmit data just fine, although the time it would experience would be much slower... | [
"another problem would be the red shift if the probe was going at clsoe to the speed of light. At some point the wavelength would be too large to be detectable anymore."
] | [
"IF you could get a spacecraft to 1c, ",
"Then anything you like could happen. You can't answer a question with our current understanding of physics if you start with an assumption that violates that understanding."
] |
[
"(This question is bathed in ignorance): The speed of sound of an object?"
] | [
false
] | Forgive me for not having the original thread available to reference, but the question posed to was something about setting gears up around the planet and how long it would take for a rotation to reach the other side. The general assumption is that it is instantaneous; however it in fact was not and had to do with the ... | [
"1) What is the \"speed of sound\" of an object?",
"The speed of sound ",
" an object is just the speed at which disturbances travel. The air is an object, the speed of sound in air is about 340m/s. In other objects it is different.",
"2) What theories or hypothesis are used to come to this conclusion?",
"A... | [
"For Q3, the aforelinked wikipedia has a good summary on methods for measuring the speed of sounds in solids and gases."
] | [
"Were you thinking of ",
"this post",
"?"
] |
[
"Can stars exist outside of galaxies and still be visible from Earth?"
] | [
false
] | Are there any known stars that are: a) bright enough to be seen from or near Earth with any kind of equipment; b) outside of the Milky Way Galaxy; and c) known to not "belong" to another galaxy or are in transit between two? How prevalent are these stars (if they have been observed)? If they haven't been observed are t... | [
"I searched this subreddit for \"stars\" and perused all the askscience posts that came up from the last month and didn't find any similar questions. If anyone else can bring a similar thread to my attention I'll try and delete mine. Thanks for the notice."
] | [
"I searched this subreddit for \"stars\" and perused all the askscience posts that came up from the last month and didn't find any similar questions. If anyone else can bring a similar thread to my attention I'll try and delete mine. Thanks for the notice."
] | [
"Thanks MathGrunt, I'll remember that!"
] |
[
"Using only Bronze Age technology, how would you charge a mobile phone?"
] | [
false
] | null | [
"Using acidic fruit wouldn't work. While you can get a volt or two from a lemon or potato, the amperage is essentially nil. "
] | [
"My thinking was you might be able to make a battery with lemons or potatoes (depending on where you land) in series with copper and tin/zinc electrodes, strung to the charger by copper filaments. If acidic foods are not available, maybe a galvanic cell of sea water with copper and tin/zinc electrodes?",
"Then wh... | [
"Hmm, so maybe a wet battery is in order. I wonder how many orchards of lemons would be necessary for the necessary current."
] |
[
"What does /r/askscience think of the Gaia Hypothesis?"
] | [
false
] | What is your opinion of the ? The Gaia hypothesis, also known as Gaia theory or Gaia principle, proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet. ...The Gaia theory posits t... | [
"pedosphere",
"I had to google it, it just means the part of the Earth that's made of soil."
] | [
"As far as I know — and I know only what I've been told — there are actually two.",
"One is too trivial to deserve the name \"hypothesis.\" It just says that a large, complex system like the Earth will oscillate naturally around some sort of equilibrium state. This is of course true … right up to the point where ... | [
"It does have a lot of unnecessary \"junk\" in it (and I was dismissive towards it before I started interacting with atmospheric science professors). But on the other hand - it's actually ",
" in its simplicity. It's even included in several atmospheric science textbooks because it wonderfully (and simply) descri... |
[
"If light is both a wave and a particle, are distant stars' light particles affected by gravity of the galaxies they pass by on their way to us?"
] | [
false
] | Does this bend the light of distant stars so they may not actually be where we perceive them to be? | [
"Yes! This is more of a general relativity thing than a quantum mechanical thing, but still it's true. This effect was the source of the first evidence in favor of general relativity (a certain star was at a different position in the sky during a solar eclipse because the sun deflected the star's light), and a fo... | [
"Wow thanks! The wiki on gravitational lensing is exactly what I was wondering. It makes you feel so small... in a good way."
] | [
"It makes you feel so small... in a good way.",
"I know what you mean. At those times I like to read up on subatomic particles to make myself feel really big! "
] |
[
"How come light travels \"in one direction\" in transparent materials?"
] | [
false
] | During high school physics I seem to remember being told light travels slower in materials such as air than in vacuum because the photons keep getting absorbed (forcing an electron to increase its energy level) and then transmitted (returning the electron to a lower energy level) again after a brief period of time. My ... | [
"Feynman's QED lecture",
" focuses a lot on this. You're asking an important question.",
"The short answer is: photons are continually being absorbed and reemitted by atoms in the medium. They're emitted in ",
" directions, but amazingly, ",
", the photons tend to cancel out in all directions except for a v... | [
"But photons still do travel in other directions. ",
"Consider this image",
". It's a photograph showing the total internal reflection of light. As you can see, the laser is reflecting within the material and traveling in straight lines. But the camera still captures the image, showing that a significant number... | [
"Layperson here. I'll give some simple answers and let the experts expound on it if desired.",
"In response to your first point, absorbed photons are converted to heat. That's why black surfaces get hotter than white ones when exposed to the same amount of sunlight.",
"In response to your second point, some m... |
[
"Is there an organism whose genetic material lacks one of the four bases?"
] | [
false
] | I was once told about an organism (or virus, if you don't consider them organisms) whose main genetic material used only three of the four bases. I can't remember if the genetic material was DNA or RNA, but I assume it was single-stranded, logically. I believe that when he told me about this, he said that the organism ... | [
"watch out, that research is highly controversial:",
"http://www.physorg.com/news/2010-12-critics-nasa-arsenic-bacteria.html"
] | [
"I've taken quite a few genetics classes, and I've never heard of it either. Google isn't helping, so here are some things that might help you decide whether to believe it or not.",
"If it is a virus whose genome has been split into several sections (\"plastids\") then it's likely an RNA virus. Some have extremel... | [
"Just to point out, if it was missing 1 base, it would probably be missing 2. Pairs generally only bond to their \"opposite.\" This would result in only a few possible amino acids being made, fewer than is required for life."
] |
[
"How much alcohol would an average 6ft tall 185Ib male have to consume to die?"
] | [
false
] | null | [
"There's something called the \"LD50 value\", which is how much of something you can drink before you have a 50/50 chance of dying from it. For alcohol, it's about 5-8 g per kilogram of human weight. For 185 lb (= 84 kg), that's about 420-670 g of pure ethanol. Basically, an entire pint of pure ethanol.",
"So if ... | [
"Tiny change. LD50 refers to the dosage of a chemical that kills (lethal dose) 50% of the test animals and it's scaled up by weight. It doesn't necessarily relate to probability of it killing a human, that's just a guess."
] | [
"Thats 2 x 4 x 3 = 24 shots btw. That is a lot of shots for one party for most people"
] |
[
"How does VLF radio \"push out\" the Van Allen belts?"
] | [
false
] | I just read but I don't understand exactly what's going on. Are the VLF waves actually "pushing on" particles in the radiation belt? Is there some sort of "magnetic bubble" or something going on? | [
"So I've read the papers directly related to this research (",
"here",
" and ",
"here",
" - they're probably paywalled, sorry), and to answer your question, no, the VLF waves are not actually \"pushing\" on the particles.",
"As I understand it, what is happening is that the \"bubble\" of VLF waves form a ... | [
"Actually, having done some reading, this really isn't \"new\" science at all. The idea of man-made VLF waves causing scattering of electrons has been hypothesised since the early 80s, but until recently it was though to be contained to energies <500 keV. All that has happened recently it that the Van Allen Probes ... | [
"Thanks for answering! (Those articles are totally paywalled, but thanks for the links.)",
"So the VLF sort of \"eats\" the Van Allen belt because the electrons in the VLF-affected region are removed from the belt?",
"The link in my original question suggests that the top of the VLF region corresponds to the bo... |
[
"Mixing Helium and Hydrogen for balloons?"
] | [
false
] | As far as I can understand Hydrogen is better for balloons than Helium because Hydrogen gives more lift and is cheaper than Helium. But Hydrogen is pretty explosive so that's why we don't use it anymore? Helium on the other hand is a noble gas so it dosen't explode or even react with fire. But would it be possible to m... | [
"Part of the problem in what you're suggesting is answered in your understanding of noble gases. As Helium is such, it won't bond or interact with Hydrogen in any real way. ",
"The poster was not suggesting anything that implied any such thing either.",
"What you'll end up with is a balloon which over time beco... | [
"Pure hydrogen doesn't explode; as with (most) other flammable gases, you need a ",
" of air (or just oxygen) and the gas to get an explosion. A balloon filled with pure hydrogen will burn quickly and rather violently in air, but not explode the way it'd do with a mixture. ",
"What's known as the upper and lowe... | [
"What you'll end up with is a balloon which over time becomes \"layered\", with lighter hydrogen occupying the upper portion of the balloon, and heavier Helium settling more-or-less around the bottom.",
"I don't think this follows. Mixtures of gases do not spontaneously separate in general because of a difference... |
[
"Why does pressure decrease as velocity decreases?"
] | [
false
] | Using the equation A1 v2, we know that velocity and Area are inversely related. Using the pressure equation, we can say A = F/P. We can then say (F1/P1) v2. Shouldn't velocity and pressure be directly related? | [
"In your approach you ended up introducing the force acting on the fluid at each cross section of the pipe, which is a number you don't know.",
"Instead, let's look at the more general equation for incompressible fluid flow - Bernoulli's equation.",
"1/2 ρ v^2 + ρ g h + P = constant\n",
"where ρ is the fluid ... | [
"As for your title, velocity decreases as pressure increases. ",
"The other explanation with bernoullis law is correct. You can look at it as converting energy stored as pressure to kinetic energy and vice versa.",
"Intuitively, what will increase pressure? Impeding the flow of a fluid which decreases the veloc... | [
"Also gotta point out difference between total pressure and static / dynamic pressure. Total pressure would be more equivalent to the energy density comparison you made and is the addition of static and dynamic pressure. So if your pipe diameter decreases, your velocity increases, which causes a drop in static pres... |
[
"When I'm on an airplane and I look straight ahead during takeoff or landing, I feel like I can see that the plane is pointed up or down. Can I really, or does my brain just extrapolate based on other information to create this illusion?"
] | [
false
] | My relative position in the plane stays the same in takeoff or landing, so why am I able to see that we are pointed up or down when I'm just looking straight ahead? | [
"You can do this, but not with great accuracy.",
"Your visual perception is certainly affected by gravity, which like other accelerations, acts upon the vestibular organs in your inner ears.",
"We have a very fast neuron arc from these sensors to the neural circuitry that controls eye movements. Here's a simpli... | [
"On that last point. Pilots are trained to trust their instruments absolutely, if they are unsure of their attitude at night or in bad weather.",
"Your senses can very easily be confused or deceived. This ends up with a pilot thinking he's pointed up, down, or in a bank, when he is in fact doing none of those thi... | [
"This happened to me during pilot training. Your inner ear can \"reset\" to a non-level attitude so that it treats it as though it were level. You then perceive yaw, pitch, and roll based on this internal idea of \"level.\" I would have bet any amount of money my instruments were lying to me. Good thing I was with ... |
[
"Is it possible to create a device similar to an electronic device that uses photons instead of electrons?"
] | [
false
] | null | [
"Yes! Photonic and optical devices are increasingly used in place of electronic devices. Light has particular advantages when it comes to transmitting information, creating 'high quality' resonators, or interacting on a quantum level. ",
"Some examples:",
"fiber optics",
"Silicon-based optical waveguides",
... | [
"Yes, and people are. The biggest roadblock, in my view, is a lack of photonic memory at the moment. Storage times on the order of milliseconds are state of the art in a photonic integrated circuit.",
"Also shameless plug for my sub that is dedicated to this topic ",
"/r/siliconphotonics"
] | [
"The most fundamental part of electronic devices is a transistor, essentially a small device that can be switched from conducting to insulating. There have been demonstrations that this can also be done for light: One beam either goes through or not, depending on whether the other beam is on. But I imagine you see ... |
[
"Does a fish ever see it's tail?"
] | [
false
] | Settle a dispute my friend and I are having. And we're talking about a standard fish here, nothing fancy. I'm pretty sure they can, because their eyes are on the sides of their heads, but he's saying that their peripherals, are not as good as I am thinking. Thanks and much love ( :-*) | [
"Unfortunately, I can't seem to find any direct report of whether fish can see their tails but we can still try and figure it out.",
"The most convincing evidence of fish-seeing-own-tail is this ",
"video of a betta fish biting its own tail",
". At times the tail is covering the eye and therefore must be perc... | [
"A fish doing a ",
"c-start",
" (which is something nearly every fish can do as an escape response) would definitely be bending more than 15 degrees and therefore would likely be able to see its tail."
] | [
"AH thank you! I knew fish could absolutely bend their tails quite a bit but I couldn't find any info about it beyond pictures of fish. Searching \"c shape\" gave me nothing useful, but \"c-start\" is exactly what I needed! ",
"This article",
" states that they can bend almost 180 degrees!"
] |
[
"If the surrounding temperature is higher than a surface's temperature, does radiation occur ?"
] | [
false
] | I know that q_rad = C*(T_s -T_surr ), but I'm not sure about what happens if the object's temperature is lower than the surrounding temperature, is it considered irradiation in this case ?? meaning that heat transfers into the object ? | [
"That equation is about the ",
" radiation from a surface. If the right side is positive, the surface has more radiation leaving it than it is absorbing. If it is negative, there is more radiation being absorbed than emitted. In the negative case, there is still radiation leaving the surface in the form of phot... | [
"you would not be able to see an icecube in a warm room",
"Is reflection the same principle as radiation?"
] | [
"Radiation = beam of photons. You're right that in principle, photons are not reflected, but a lot of times, the scattering theory describes physical phenomena very well, so it's often described like that.",
"On the main topic: Every (real) object emits thermal radiation. If two objects are the same temperature c... |
[
"How do spacecraft/rovers/space probes communicate back to earth from such long distances?"
] | [
false
] | null | [
"On the far ends, they have a low power (20w) radio transmitter with a highly directional antenna pointed at Earth. At this end we have very sensitive radio receivers connected to HUGE and highly directional radio antennae pointed back at the spacecraft. Transmissions from Earth to the spacecraft are sent at ... | [
"In case of rovers and landers, they use orbiting satellites as relays (for example Mars rovers communicate directly to orbiters and then orbiter sends data back to Earth)"
] | [
"It's probably also worth pointing out that the transmission datarates are also extremely slow by our modern terrestrial standards, which improves the signal-to-noise ratio dramatically. New Horizons now transmits at less than 1 kbps at its current distance.",
"EDIT: ",
"Here's a lovely picture of one of the en... |
[
"Hot water and the urge to urinate: What's the deal?"
] | [
false
] | null | [
"If I assume by your question that you mean the \"hand in warm water\" trick or something similar, then I couldn't really find a valid answer to the question, or any literature associated with it. ",
"Immersion diuresis",
" is the closest thing I could find relating to the phenomenon, but it involves full subme... | [
"I would also speculate that it has to do with warm water inducing muscle relaxation, specifically of the pelvic floor, which is a precursor to urination."
] | [
"Not a totally scientific answer, but Mythbusters have tried it and have called it Busted. You don't get the urge to pee, at least while sleeping, if they submerge your hand in warm water."
] |
[
"How does matter \"remember\" that it is moving a direction after an initial force is applied to it?"
] | [
false
] | null | [
"Momentum is conserved."
] | [
"Where? So to speak. "
] | [
"Everywhere, all the time. Whatever momentum an object has in one instant of time will be the same in the next instant of time, if there is no net external force acting on the object.",
"If there is an external force ",
" acting on the object, and its momentum at time t is ",
"(t), then in the next instant of... |
[
"Do sleep walkers still get the same, sufficient amount of recuperation as if they slept soundly?"
] | [
false
] | After watching the reaction video of the mother who was treated to a video of herself sleepwalking (for what I assume is the first time), I was curious if the brain can still recuperate as efficiently when someone is sleepwalking as if they had slept soundly. | [
"No, sleep walkers generally walk during the SWS (slow wave sleep) phase of rest and require a higher level of consciousness than is typically seen during REM (rapid eye movement) because their brain is partially engaged during the walk.",
"But, this varies depending on the complexity and length of the sleep walk... | [
"That said, would lucid dreamers then have a similar amount of recuperation as a normal person?"
] | [
"Lucid dreaming is somewhat of a misnomer and a contradiction. ",
"So, lucid dreaming wave patterns (higher concentrations of beta frequency band: 13-19 Hz) interrupt the predominant wave patterns of REM sleep (higher concentrations of delta frequency band: 0.5-2 Hz) and effectively remove the sleeper from stric... |
[
"How valid is the Myers-Briggs Type Indicator?"
] | [
false
] | I'm also not sure if this is a proper question for askscience, but I didn't know where else to go. is this test an accurate determination of a person's psychology profile? If not, what makes it inaccurate or wrong? In anecdote, I've always found that this test can accurately describe myself and close friends I've had t... | [
"Pretty much bunk.",
"See:",
"Key passages:",
"\"The test does have some severe inherent problems. It's been found that 50% of test takers who retake it score differently the second time.\"",
"\"From the perspective of statistical analysis, the MBTI's fundamental premise is flawed. According to Myers & Brig... | [
"Some researchers have interpreted the reliability of the test as being low. Studies have found that between 39% and 76% of those tested fall into different types upon retesting some weeks or years later.",
"So, perhaps not very accurate."
] | [
"Personality does change a little over the course of your life, and more so when you're younger, but a high number like 83% would be entirely inconsistent with what we know about people. This would mean that people were constantly having significant personality overhauls, and we know that this isn't true.",
"Howe... |
[
"Is there a difference between Cytotoxic T cells (killer T cells) and Natural Killer (NK cells)"
] | [
false
] | I know they are both WBC's but are they different types of lymphocytes? | [
"NK cells are an interesting part of microbiology. To put it simply:",
"Cytotoxic T cells recognize a major histocompatibility (MHC) I complex which contains foreign protein fragments on the surface of the cell using a TCR on a T-cell's surface. The foreign protein has been digested and broken down within the aff... | [
"Actually there is a growing body of evidence indicating that NK cells may in fact form memory populations ",
"1",
" ",
"2",
"."
] | [
"This makes it super clear to me!! Thank you!"
] |
[
"What is different between Earth and Mars that gives Earth a Magnetic field, while Mars does not?"
] | [
false
] | null | [
"The molten semi-liquid core, made primarily of iron, for the most part. Mars's core is iron, but it is not in a liquid state, rather solid. It has to do with the fact that there is circulation, or \"rotation\" within it. That is mostly what generates a magnetic field, movement of a magnetic conductor."
] | [
"The reason Earth's core is still liquid but the core of Mars isn't is that Earth's core is more massive, and so it still retains some of the heat from planetary formation and radioactive decay of heavy elements while Mars' core cooled off faster due to the planet's smaller size."
] | [
"Both planets have a crustal magnetic field, roughly the same order of magnitude nT. The Mars crustal field is distributed around the south pole in a pretty interesting way. This implies there was a core field at some point in the past, since we don't think it was made by impacts.\n(Earth crustal field: ",
"htt... |
[
"What happened before the Big Bang?"
] | [
false
] | I'm relatively ill-educated in physics, but I'm interested in the topic. I was thinking about the Big Bang and realised that, whilst I knew that this event was acknowledged as the beginning of our universe, that I didn't know what occurred before it. So I ask, what happened before the Big Bang? Is there a scientific co... | [
"the current accepted answer to that question is \"that question doesnt make sense.\" there was no \"before\" the big bang. Now some people beleive we live in a sinusoidal universe meaning before what we know as the universe was another universe that that crunched down to a point then big bang to our universe."
] | [
"No, it's not beside the point. It ",
" the point. You've conflated \"north\" with \"up\" here, and you're imagining that moving north somehow is equivalent to increasing your altitude.",
"Cut that out. Stop thinking of the Earth as a ball hanging in space. Focus your attention solely on the ",
" of the Earth... | [
"Since our every experience is constrained to the constant of time, what happens outside of that isn't describable it a way we could understand or relate to.",
"No. This is completely the wrong way to look at it. You're thinking of it as something ineffable, mysterious, beyond comprehension. That's wrong. You're ... |
[
"I've heard it said that we should use hand sanitize less frequently because it encourages the evolution of sanitizer resistant super bacteria. Why is this not a concern with traditional hand washing?"
] | [
false
] | If both hand washing and hand sanitize get bacteria off of your hands (away from where they want to be), couldn't hand washing encourage the evolution of soap-and-water resistant bacteria? | [
"Traditional hand washing removes bacteria from your hands rather than attacking it chemically (unless you us anti-bacterial soap), so the bacteria does not develop the d same kind of defense. "
] | [
"Is this actually a concern with proper hand sanitizers which are just ethanol and water with a little gelling agent? "
] | [
"There are actually some bacteria which are more resistant to ethanol than others, probably due to a different cell wall structure. It's not clear whether or not ",
" are breeding resistant bacteria by using ethanol. Even if we are, it's probably still less of an issue than specific anti-bacterials. ",
"http://... |
[
"[Chemistry] Is Cupric Sulfate + Methanol dangerous?"
] | [
false
] | I want to mix (I bought the type that is not anhydrous) with some methanol (Wikipedia says it dissolves). Cupric Sulfate is what they use in fireworks and flame tests to make green fire, so I am planning on filling a water gun with this solution and shooting it at a bonfire in a couple weeks. First, would this solutio... | [
"Also worth noting that one of the problems with using alcohols in flame tests is that they burn and give off their own emissions, which can sometimes drown out the color you're trying to use. Methanol is better for this than ethanol, but water is clearly the better choice here."
] | [
"Why do you want to mix it with methanol? If you're shooting at a flame, water would do just fine to change the flame colour. What you're trying to make is a flame-thrower - which is dangerous. Methanol may also be less spectacular than you think, since its flame is faint and burns quickly - the fact that it's fain... | [
"It'll even be better if you can modify the nozzle so it sprays a mist instead of a jet. Better yet, just use regular cleaner spray bottles. This way you won't accidentally kill the flame."
] |
[
"Are solar panels that are glass-faced (for protection) significantly less efficient at creating energy than bare panels because glass prevents the transmission of UV light?"
] | [
false
] | null | [
"One, only a small portion of the energy in sunlight is in the UV.",
"Two, photovoltaic cells work by turning one photon into one electron-hole pair. A photon with too little energy (too long a wavelength) will produce nothing. A photon with excess energy (a short wavelength) will \"waste\" that excess. Single-ju... | [
"Good answer. Readers should note that in the linked spectrum, it's the red curve that's relevant--the atmosphere already reduces the UV significantly.",
"The spectrum there is available as a data file at ",
"https://www.nrel.gov/grid/solar-resource/spectra-am1.5.html",
" If you take 350 nm as the cutoff of... | [
"Something that hasn't also been specifically mentioned is that the UV energy that is partially blocked by the glass also improves durability of PV modules.",
"While UV energy only a small portion of the overall energy, the large photon sizes make it the primary cause of polymer photodegradation. A slight reducti... |
[
"Would it be possible, given a person's prescription, to create an altered image that would appear normal to that person?"
] | [
false
] | [deleted] | [
"I was refraining from answering before because I'm not a full expert in the field, but I've got some experience, and given the other... not very helpful \"answers\" below, I'll give it a shot.",
"Blurriness from bad vision, while looking at a flat plane (computer monitor), is a convolution filter on an image (a ... | [
"Ok, my theory seems to not be incorrect. However the contrast achieved using this method is very limited since we can't have negative intensities.",
"http://i.imgur.com/3mIRy.png",
"For reference i first show the process of restoring a blurred image. The convolution kernel is a combination of a disk and a Gaus... | [
"Adding to this. (from a signal processing background) ",
"A convolution filter (like blur, defocus etc) is the same as multiplying the ",
" function in the frequency domain (fourier domain)",
"This means that the only information truly lost is for frequencies where the transform of the blurring filter is ze... |
[
"What's the correlation between sexual abuse and trauma and it causing mental illness (specifically long term mental illness and emotional damage)?"
] | [
false
] | I am aware of women both in my family and in extended relationships that endured sexual abuse at some point in their lives that led to long-standing mental illness, be it borderline personality disorder, manic depression, anxiety disorder, post traumatic stress disorder, etc. One person in particular has basically been... | [
"This is a really complicated question. TLDR at the bottom.",
"One of the most famous scientific controversies in the history of the United States arose from a question very similar to yours. It's called the ",
"Rind et al. controversy",
" (link to wikipedia). Rind et al. wrote a paper about the self-repor... | [
"That was a really well-written break down. Really interesting that the study was condemned like that."
] | [
"Thanks. It was a really big damn deal at the time because politicians basically ",
" to vote to condemn it or their opponents would make them look like sympathizers of child-abusers. But at the same time, politicians have practically zero qualification and literally zero authority to tell scientists that they'... |
[
"If you were locked up and only had access to 1 litre of water, how should you comsume it in order to survive the longest?"
] | [
false
] | null | [
"A still requires material that were not part of the original conditions."
] | [
"Before drinking any of it, store your urine if it's dilute. You're probably pretty hydrated already, so you'll be losing a lot of water through there. When your urine starts to get darker(Probably only after 1 piss), stop, and start drinking small amounts of water. Concentrated urine will be very bad for you, and ... | [
"A evaporating chamber with a connected cooling chamber. Usable in deserts with two 2l plastic bottles and tape to turn urine of any colour into clear water. Put sand over the cooling chamber. "
] |
[
"At one end, photons experience no time. Is there anything at the other end which has experienced more time?"
] | [
false
] | null | [
"Photons do not have a rest frame. So the statement \"photons experience no time\" is meaningless.",
"This thread in the FAQ answers your question.",
"https://www.reddit.com/r/askscience/wiki/physics/exceed_speedoflight",
"edit: This second one might answer your question more directly.\n",
"https://www.redd... | [
"I thought time stood still at c. What do you mean by rest frame?"
] | [
"The rest frame of a massive particle is one in which it is not moving. Photons always move at ",
", and so they do not have a rest frame. So it is meaningless to ask questions like \"what does a photon experience\"."
] |
[
"Is there such a thing as \"hangtime\" during jump?"
] | [
false
] | i often hear commentators in various sports comment about certain players ability in air and how they get hangtime in air, or ability to stay in air for longer than opposition while being shorter. Is it simple physics of having a better jump or is there a special technique or variable that allows you to outlast someon... | [
"To a limited extent, yes. By moving your limbs in particular ways you can alter where your center of gravity is. While the center of gravity will always follow parabolic path, your body doesn't always have to. A classic example of this is the Fosbury flop used by high jumpers and pole vaulters. "
] | [
"I think the perception of hang-time is mostly driven by how far horizontally the player moves during the jump. It's the flattening of the top of the parabola that seems most impressive to me."
] | [
"Height has nothing to do with time spent in the air, though being taller does improve your reach. Strength of the jump is basically the only factor in the time you spend in the air. The other things like limb position affect it a little bit but usually not to a noticeable amount."
] |
[
"Similar to increasing wealth gap, are we experiencing an increasing educational gap? Are well-educated getting more educated and under-educated staying under-educated?"
] | [
false
] | Edit: Thanks everyone for many different perspectives and interesting arguments! One statistic brought up was global educational attainment rising overall, which is a quite well-known development, and I'm glad it is taking place. Another point brought up was education and degrees. In this question, I don't necessarily ... | [
"TLDR: Yes and no. There is no direct connection between having and education and then getting more education as a result. However, education leads to more money and more money leads to more opportunities for education and more success in obtaining education, both for an individual and for that individual's childre... | [
"The question is about education disparity among classes, not the general trend of educated populations."
] | [
"I think you need to define \"we\". This would be very different for each countries laws. Things like access to education, ability to use that education to actually benefit lifestyle, etc, will dictate the answer to this question."
] |
[
"Why do neutrinos oscillate but electrons don't?"
] | [
false
] | Are there any interesting theories as to why neutrinos would oscillate but not electrons given that they're both leptons? | [
"By definition.",
"Basically take ",
"this answer of mine",
" and replace the up-type quarks (u,c,t) with the charged leptons (e,μ,τ) and replace the down-type quarks (d,s,b) with the three neutrinos. Exactly the same thing happens with the leptons.",
"(There's a difference from quarks in that the neutrinos... | [
"So ",
"u/rantonels",
" answer is correct but assumes you are familiar with quarks; I will assume you are not. ",
"Okay so basically the reason is that we have to be careful about what we call a particle when we right down a Quantum Field Theory. The definition is basically something like \"If I can seperate ... | [
"As you said within the standard model the flavour of a neutrino is defined by the charged leptons it produces in a weak interaction. The question is if there is a possibility assuming beyond the standard model physics.",
"There is a fantastic paper by ",
"Akhmedov",
" that discusses everyting about the oscil... |
[
"How do stem cells know how to arranges itself in space, defining tissues boundaries and shapes?"
] | [
false
] | Hi! I was always intrigued by how stem cells work together to build a complete organ, and parts of the human body. Like, for example, to build an arm, how do stem cells "know" that they have to go X cm lenght to start to build the wrist. And moreover, how do that X cm lenght converts to Y number of cells. I know it's n... | [
"It all comes down to chemical reactions and signals, like you said. At the most general level, cells will differentiate one way or another based on a presence of a signal, which usually means that the signal needs to reach a certain threshold for something to happen, and if it doesn't reach that threshold, then an... | [
"Chemical markers/messengers. Cells spew out molecules that other cells “read”. Based on what molecule it is the cell differentiates itself into a particular type of cell, e.g., liver or neuron. Then in turn it spews more messenger molecules for the other cells to “read”. Imagine a soup of these messenger molecules... | [
"I would like to add to the other answers here that the signals which cells use create order structures (tissues and organs) are not purely chemical, they can also be mechanical. For example, an epithelial cell (the epithelium being the surface of a tissue) should be surrounded on all but one side by other cells, a... |
[
"If skin sheds and regrows daily, then why do scars develop?"
] | [
false
] | Scar tissue seems much different than normal skin tissue. It almost seems more fragile. Why would replacement skin grow if it's weaker or a different texture? Follow up: what leads to scars forming? I got a paper cut on my forearm, and it's still red, although it'll disappear after a couple of days. Yet picking small s... | [
"The short answer is that the body is mainly concerned with patching the hole in the skin as fast as possible. It does this with fibrous tissue as opposed to the normal skin cells, which then makes up the scar. The smaller cuts can be tightened and heal without the need for scar tissue formation.",
"As to the pic... | [
"Heres a hopefully clearer explanation. There are multiple layers to your skin. The top layers are made of the cells you're thinking of as skin cells, or keratinocytes. These cells form a barrier that helps keep water in and the environment out. These cells are linked by proteins and as they mature they're shed. Th... | [
"The body leaves the scar tissue because there's no reason to replace it as far as the body is concerned. The scar is actually not fully healed for a long time after the wound is closed, the pinkish hue that can be seen in the scar is capillaries continuing the healing/modeling process. ",
"The 'scarred' cells do... |
[
"How effective are two dose vaccines if you get the second dose long after the recommended time interval?"
] | [
false
] | This has become relevant due to Biden’s plan to release COVID-19 vaccines that were being previously reserved as second doses. Let’s say you receive the first dose of a vaccine and it is recommended to get the second dose one month later. But instead you do not receive the second dose for multiple months or even a year... | [
"Well there is some research. Mainly being that just getting the one dose is only around 50% effective at preventing covid, so really you aren't very protected until you get the second dose when protection effectiveness is like 95% or more \nAs far as other vaccines that area two shot series, it's a difficult compa... | [
"so really you aren't very protected until you get the second dose",
"It's not really as clear-cut as that. Looking at the ",
"initial report",
", it looks like the 50% figure is from observing:",
"After the first vaccination, PsVNA responses were detected in less than half the participants, and a dose eff... | [
"Out of curiosity, what happens if you get the 2nd vaccine shot 2 or 3 days after getting the first one. I might be able to book a 2nd appointment 2 days after getting the first one and am not sure if I should or not?"
] |
[
"What causes galaxies in our universe to move?"
] | [
false
] | [deleted] | [
"The predominant motion of the universe depends on what scale you're looking at. If you look at small scale motion then gravity dominates the motion. So we see all the familiar gravitational phenomena. For example, the Milky way has a smaller galaxy, known as a satellite galaxy, orbiting it called the Ursa Minor Dw... | [
"So space kind of expands \"from under us\" and the reason, e.g., galaxies are getting further apart is that the forces binding them are unable to compensate for the rate of expansion, however the reason we are still the same size is that the bonds that make us up can counteract this expansion?"
] | [
"Yeah, that's right. Worth noting though that you wouldn't get bigger, you would be pulled apart since all the particles you're made of would get further apart. Just a technicality."
] |
[
"Where can I find a good explanation of String Theory?"
] | [
false
] | null | [
"You might try Barton Zwiebach's book ",
", which is geared towards advanced undergraduates."
] | [
"This is cool. (short add first) NOVA on PBS\n",
"http://video.pbs.org/video/1512280538/"
] | [
"String theory is very (very) mathematical, what sort of mathematical background do you have?",
"I found that with all areas of physics there is a lack of good material for advanced laypeople, ie. material for casual reading more advanced than say \"The universe in a nutshell\" that is not undergrad level."
] |
[
"Time dilation question"
] | [
false
] | null | [
"In your calculations for [1] and [2] you use the distance between Neptune and the Earth as seen by the stationary observer on Earth (Captain Kirk) and the velocity of the ships Alpha and Omega (again measured by Captain Kirk). This is the time that Kirk will age before the ships pass Earth. There is nothing more t... | [
"One additional question - how would you calculate the age of Kirk from the frame of reference of each ship?",
"You take the fact that when Omega (for example) passes Earth Kirk is 8.06 hours old, then calculate his age at any moment using the fact that Earth time is slowed by a factor of ~0.87 in Omega's referen... | [
"Gah, ok, that makes sense (that my assumptions are incorrect). I do want to learn Special Relativity the easy way, so thanks for providing a learning resource, and thanks for the response. "
] |
[
"How and when does a virus cross over to another species?"
] | [
false
] | Crossing over requires another host with similar evolutionary lineages, but that's about the extent of my knowledge. | [
"In many cases, viruses evolved to be well adapted to a certain species. This is true of several steps in its life cycle: how it's transmitted, what surface proteins in binds with to gain entry into the cell, which proteins it can interact with to replicate, how it shuts down the immune system, etc. This is why i... | [
"You have to remember than the \"virus\" is just some genes in a protein shell. Everything it does is dictated by chemistry and physics; it doesn't really \"decide\" anything. Take avian flu for example: a duck sneezes out droplets filled with virus. Wherever that droplet goes, that's what the virus will try to ... | [
"Thank you, I found your explanation helpful. Can you provide any insight as to when a virus crosses over? As in, when does it \"decide\", so to speak, that there is a need to jump species? Or is it by sheer chance? Because if the crossing over doesn't work, isn't that equivalent to suicide?"
] |
[
"Without a cataclysmic event like the Cretaceous–Paleogene extinction event, would intelligent human life still developed and if so would it have happened millions of years later?"
] | [
false
] | null | [
"We also run ",
"/r/AskScienceDiscussion",
" which would be a good bet."
] | [
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):",
"For more information regarding this and similar issues, please see our ",
"guidelines.",
"If you disagree with this decision, please send a message to the moderators."
] | [
"Thank you. Sorry to not meet the criteria. Is there another sub for this sort of question, like a \"sciencewhatif\"?",
"Thanks."
] |
[
"Why won’t the rocket equation give the same answer for simple conservation of momentum?"
] | [
false
] | you know how the ideal rocket equation says Delta V = Vexh ln(m0/mf)? If I use it for a very simple example, like a bowling ball with an ice skater, I get two different result, and I don’t know why. Here’s what I mean: Say that a 50kg ice skater with a 10kg bowling ball launched the ball at 10 m/s in one direction. Fro... | [
"In the situation you describe, the change in mass is being treated as an impulse, while in the case of the rocket equation the mass is being expelled continuously as a function of time.",
"Referencing ",
"this",
" derivation of the rocket equation, you can see that the differential equation",
"m dV/dt = -v... | [
"Just as a notational thing, I wanna be clear that by δ(t), is that referring to the Dirac delta function at t=0?",
"Yes.",
"In that case, would the units still be in seconds? I’m just trying to make sure that the units make sense when you preform the integration since you’d be multiplying both sides by dt.",
... | [
"In that case, I guess one could say that you could come to very close values for delta V by just using algebra and conservation of momentum, with no need for calculus. Or maybe if you could write a program or something and come to a good value with just introductory high school physics. Also this is the first tim... |
[
"How is gender (not sex) biologically structured? Why does gender dysphoria exist?"
] | [
false
] | null | [
"I wrote something like a year ago on the epidemiology of Gender Dysphoria for an assessment in my abnormal psychology unit. It might be of some use to you.",
"Gender dysphoria is the experience of distress resulting from an incongruence of a person’s psychological and emotional gender identity and their biologic... | [
"First theory: you get two \"doses\" of testosterone production while in utero. It may be that the timing or administration of these doses is abnormal. "
] | [
"The second believes there is a critical time in early life development where environmental factors influence gender identity. Parents reinforcing opposite gender roles or stereotypes, abuse, or other abnormal situations during this time period may disrupt the normal \"sense of self\" time period "
] |
[
"How many generations (or time) back would we have to go before being unable to produce fertile offspring with one of our ancestors?"
] | [
false
] | Bonus question: What determines wether or not two organisms can reproduce? | [
"For the first question, ",
", but ",
" at least ",
" ",
" 500,000 years (sorry, I forgot about Neandethals when I was first writing this answer...silly me).",
"Let me answer the bonus question next, and then I'll give a few thoughts on your main question.",
"The place to start is with the genetics. An ... | [
"I would just add that an important factor for fertility of offspring is chromosome number. Mules are perfectly functional as individual animals but are sterile because their parents had different chromosome numbers, so it is nearly impossible for them to pass on a complete haploid genome. The great apes, other t... | [
"I can't access your final link (it goes to the UCDavis library login), but cheers that's an awesomely detailed answer."
] |
[
"When will energy be free?"
] | [
false
] | null | [
"Electricity will only ever be \"free\" if it is covered by taxes.",
"People are needed to produce electricity, or at least produce the objects that produce electricity, and they need salaries to continue to work. So it won't be free."
] | [
"We're getting bombarded by free energy all the time. The issue is transforming that energy into a form that does useful work. If it is cold outside, I am getting \"free\" heat by standing out in the sun, which serves a useful purpose of heating me up. However, unless I had the means to transform that energy int... | [
"you're assuming the current \"capitalist\" configuration of society. That's akin to saying a couple hundred years ago that slavery will never be outlawed, or saying even a hundred years ago that landing on the moon is inconceivable."
] |
[
"I've learnt that bacteria can become spores and preserve themselves for thousands of years, but how do they survive if DNA has a half-life of 521 years?"
] | [
false
] | [deleted] | [
"One thing to remember with the decay of DNA is that it's not necessarily a radioactive decay. The decay is typically from the molecular bonds being broken. This is commonly caused by chemical reactions involving water and oxygen. When these bacteria go into stasis, they are still alive but chemical reactions... | [
"Carbon-14 makes up about 1 ppt of the total carbon in the world. Some of it will inherently become incorporated into DNA, when it decays it decays by beta emission and becomes Nitrogen-14. This would probably break up the ring structure of whatever base pair or sugar it is incorporated into in the DNA. ",
"Fu... | [
"Carbon-14 makes up about 1 ppt of the total carbon in the world. Some of it will inherently become incorporated into DNA, when it decays it decays by beta emission and becomes Nitrogen-14. This would probably break up the ring structure of whatever base pair or sugar it is incorporated into in the DNA. ",
"Fu... |
[
"Should we see a mild flu season?"
] | [
false
] | In theory, should we be seeing a lower than average amount of flu cases this year due to the enhanced social distancing, mask wearing, and sanitization? Will we actually? Why or why not? | [
"Influenza cases in the Southern Hemisphere’s flu season were extremely low, and so far in the Northern hemisphere cases have been far below average. ",
"Following widespread adoption of community mitigation measures to reduce transmission of SARS-CoV-2, the virus that causes COVID-19, the percentage of U.S. resp... | [
"My hospital posts statistics daily due to Covid and we are behind the number of flu cases this year in comparison to the last ten years."
] | [
"It's almost like washing your hands, using hand sanitizer, and staying away from other people can reduce the transmission of the flu virus too!"
] |
[
"On Jupiter, will more superstorms the size the Great Red Spot eventually form, or are the positions and types of storms relatively constant?"
] | [
false
] | Hurricanes and big storms on Earth move around and change size, but does that happen on Jupiter? | [
"I'd expect that Jupiter's weather calculations would be even more chaotic",
"I did my PhD dissertation running climate models of Jupiter. Surprisingly, this is ",
" the case.",
"Earth is actually the planet with the hardest weather to predict. That's because we live on the only planet with atmosphere and oce... | [
"The great red spot has been a standout feature of Jupiter for at least a couple hundred years, possibly a lot longer. Clearly it's not a short-lived feature like storms and hurricanes on Earth.",
"But as for its evolution and the formation of other storms like it, that's all unknown AFAIK. Understanding our own ... | [
"Sorry, bit too much personal info in there to share publicly. The part of my dissertation that was about Jupiter (the majority was actually about Uranus) summarized, though:",
"Until recently, the Great Red Spot (GRS) was the only massive vortex on Jupiter that was also red. It's very unclear why this is the cas... |
[
"Why don't candles smell until you blow out the flame?"
] | [
false
] | null | [
"TLDR: The stuff you smell is being burned up while its lit. "
] | [
"Complete combustion turns all the components of the candle into gases, which is why expensive candles tend to run very little. The wax and wick mixture is perfect for a virtually perfect, clean flame. ",
"In combustion of the solid wax, first it must be vaporised. This vapour normally rises into the blue core of... | [
"Ask science is not the place for guesses, especially ones as wrong as this.",
"Read the rules for the subreddit!"
] |
[
"What does the SEIR model of infection actually tell me?"
] | [
false
] | There are so many formula's but it doesn't mean much to me. I have a definition for most part of the model but I can't seem to put them together. I there a succinct way to describe it? Phone grammar | [
"The SEIR model is one way of projecting how many individuals in a population are ",
"usceptible ",
"xposed ",
"nfected and ",
"ecovered when considering an epidemic that allows an infected individual to immediately transfer the parasite to another individual. ",
"Some parasites have latency periods wher... | [
"It allows you to model the rate at which an infectious disease spreads through a population, and as such the impact an infectious disease will have on that population. Will it be a minor outbreak or a full blown epidemic? What happens if the disease mutates such that it becomes more contagious, or what happens if ... | [
"It's a way of describing how the population is divided (into the SEIR categories) in relation to a particular infection, and how individuals transfer between categories. Just like with any model, if you know a few parameters (for instance, the proportion of the population in each category, or the rate that individ... |
[
"Even though we share 98% of our DNA with chimpanzees, we can not interbreed. Since it is known that Humans (Homo-Sapiens) interbred with Neanderthals, is there any estimate on how close of a match our DNA was?"
] | [
false
] | null | [
"A recent estimation is that 7.9% of the differences between humans and chimps occurred after the split from Neanderthals, so that would put the estimate of differences in our DNA from Neanderthals at around 0.2%. In other words, modern homo sapiens share around 99.8% of their DNA with Neanderthals.",
"http://hum... | [
"According to my Anthropology text (A Human Voice Exploring Biological Anthropology) on pg. 270 it states that it varies based on location with some areas being as high as 62% (",
"Sankararamann et al, 2014",
") and in others as low as 0.1%."
] | [
"Do you mean that the genetic similarity between the two species varied across homologous genomic loci?"
] |
[
"Does the mirror test really prove consciousness or self-awareness?"
] | [
false
] | And does failing the test really show that you aren't conscious or self-aware? It seems like an incomplete test to me, but maybe I'm missing something. I feel like an animal can be conscious but still lack the reasoning power to realize that the animal in the mirror is himself. Conversely, I feel like an animal can be ... | [
"Posted this photo on my facebook last month:",
"Forcing Trunks to accept the fact that he's a dog. He wishes he took the blue pill instead.",
"We showed my dog the mirror for a while while interacting with him to help him understand that he was the one in the mirror. We don't have any ground level mirrors in t... | [
"I'm not sure I'd call the mirror test a measure of ",
", but that's more of a philosophical matter. It certainly ",
" a measure of self recognition, of course - or, more accurately, a certain ",
" of self recognition. ",
"Animals that normally fail the mirror test may still possess a degree of self awarene... | [
"haha awesome story",
"poor thing, probably thought he was gonna grow up to have hands, stand up, and eat at the table and everything."
] |
[
"Gravity Probe B has essentially perfectly spherical gyroscopes that are supposedly only 40 atoms out at any point. Would these be, relatively, the roundest objects in the universe?"
] | [
false
] | If the gyroscopes are the size of ping pong balls (~2.5 cm diameter) and only have an error of a maximum of 10 nm, relatively, they would be flatter than neutron stars would they not (an error of up to 5 mm over a diameter of somewhere around 15 km)? Is anything more round and spherical than this? | [
"The gravity probe b website claims they are topped in sphericity by neutron stars ",
"http://einstein.stanford.edu/TECH/technology1.html",
". If you want to stretch the definition of object slightly, I believe electrons are the most spherical things ever measured ",
"http://www.youtube.com/watch?v=yYZhNBYYmL... | [
"The associated charge distribution does, and that's what has been measured to exceptionally high precision ",
"http://www.nature.com/news/2011/110525/full/news.2011.321.html",
". When you get right down to it though, nothing really has a shape; everything is just a charge/mass distribution on some level."
] | [
"If for \"round\" you'll accept a circle rather than a sphere, then a possibility is the orbits of some binary pulsars. Due to gravitational radiation, they naturally circularize their orbits over time. We can measure the eccentricity of the orbits from pulsar timing experiments. ",
"One pair in particular(pdf... |
[
"Why does Venus rotate so slowly?"
] | [
false
] | I remember reading that Venus rotates at a rate much slower than Earth and have been wondering what the cause of this is. | [
"It took me less than 5 minutes to do the reference trail on the Wikipedia article, which leads to ",
"two",
" ",
"articles",
" by the same authors that describe ",
" and ",
" conclusions that lead to the points about tidal locking and thermal tides. Laskar is a well respected researcher, but two papers... | [
"http://en.wikipedia.org/wiki/Venus",
"according to wikipedia its because the atosphere is so dense it has a tidal (like the sea on earth) effect on the planet, where its rotation actually switches direction over billions of years, it is currently a retrograde motion, but slowing again. eventually it may rotate ... | [
"Sources please."
] |
[
"Why do airplanes seem louder when it's really cold outside?"
] | [
false
] | null | [
"Hey guys,",
"I've come up with some possible explanations for the loud airplanes. While we're all waiting for the airport people to call me back, I thought I'd share some with you.",
"Imagine you bought a McChicken sandwich but couldn't eat it for a few days. Your next move? Put it in the refrigerator. Delicio... | [
"I am going crazy. Somehow, cold air is more dense than warm air. I'm trying to imagine a hot air balloon here. Obviously understanding the answer to this has opened up a pandora's box of science questions which is revealing that I can't remember anything from my high school science courses. Yikes. "
] | [
"I am going crazy. Somehow, cold air is more dense than warm air. I'm trying to imagine a hot air balloon here. Obviously understanding the answer to this has opened up a pandora's box of science questions which is revealing that I can't remember anything from my high school science courses. Yikes. "
] |
[
"When I look straight up into a perfectly clear, blue sky, What Exactly am I looking at?"
] | [
false
] | null | [
"i'll give some nonstandard answers to this relatively standard question. (standard answer is that you're looking into the great void, and the blueness is merely scattered light from the sun, rather than the 'color of' something, which glosses over the fact that everything else you look at outside in the daytime is... | [
"You're looking at outer space!\nThe blue color comes from a phenomenon called ",
"Rayleigh scattering.",
" This is the elastic scattering of photons, or more simply put, scattering in which the photons keep their original energy. This scattering is caused by the atmosphere. Now, as for the color, blue and viol... | [
"Yeah!",
"Also lots of little moving dots, many of which execute a sine-wave wiggle motion. Those are white blood cells which form gaps in the blood-filled vessels in front of your retina. ",
"Scheerer's phenomenon",
" or \"blue entopic phenomenon.\" The wiggle-motion is actually a capillary, and if you wa... |
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