AskScience AMA Series: I am /u/pengdrew, a physiologist that studies Penguins! I study the physiology of aging in wild penguin species and am here to any questions you have about penguins, aging and physiology/ecology! AMA!

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• AskScience AMA Series: I am /u/pengdrew, a physiologist that studies Penguins! I study the physiology of aging in wild penguin species and am here to any questions you have about penguins, aging and physiology/ecology! AMA!
• What's happening in my brain when someone says something to me, then I ask "what?" and immediately realize I heard them perfectly in the first place?
• Is evolution guaranteed where there's life?
• When talking about brain waves, what actually are these waves?
• The diagnosis rate of depression is 6.7% of adults, so why is it as a "disorder" if having the condition is not a statistical anomaly?
• What makes Quantum mechanics and the General Theory of Relativity incompatible?
• What is a lens flare and why does it happen?
• Why are 1, 3, 7, and 9 the only numbers whose multiples can end in any digit?
• What are meteorites made from?
• Is there any material that is not a solid at absolute zero?
• If you exercise when it's hot outside, you certainly feel more tired, but do you actually burn more calories?
• How does inhaling work? You're not creating a vacuum or something, right?
• If the Dead Sea is 400m below sea level, would it be possible to refill it to sea level by simply building a canal to it from the Mediterranean?
• If two black holes spinning in opposite directions of each other were to come close to one another and eventually merge, what would happen to the event horizon before and after merging?
• Do gravitational waves get "red" shifted like light and radio waves do?
• Are there objects far enough away from us that light they have emitted has never reached Earth, but will in the future? Or are all such objects traveling away from the Earth faster than the speed of light?
• How can the quality of a video deteriorate if it is uploaded, downloaded and re-uploaded to and from the same location?
• An object in space gives off sound waves with the same amount of energy as light radiation from the Sun and at the same distance from Earth as the Sun. Would we be able to hear the sound on Earth?
• How does a stem cell know in which way it has to specialize depending on its place in the embryo ?
• If I electrify the pan I am using for melting a chocolate bar, will it have any results the article mentions?
• Do we experience time dilation relative to the rest of the universe? If so, how does it affect us?
• Gas expands when heated. Gas cools when it expands. What gives?
• Would a empty hard disk weight differently than a full one? (considering both hard disks are identical)
• How to achieve a perpetual sunset?

AskScience AMA Series: I am /u/pengdrew, a physiologist that studies Penguins! I study the physiology of aging in wild penguin species and am here to any questions you have about penguins, aging and physiology/ecology! AMA! Posted: 22 Jun 2016 04:20 AM PDT Hi Reddit! I am a PhD physiologist and ecologist studying the physiology of aging in wild penguins! I am currently in the second year of my PostDoc studying stress hormones, aging, and ecology in Spheniscus penguins. Specifically my work explores the relationship between stress hormones, telomeres and life-history decisions (reproduction, mating, growth, etc) in a very long-lived seabird! I'm excited to talk about: Penguin Biology Physiology of Aging / Physiological Ecology Penguin & Seabird Ecology General Physiology/Ecology Graduate School & PostDoc in Biology Other fun stuff! A few other notes on me: B.A. in Biology from a small Liberal Arts College (gasp!) PhD in Biology from a Top R1 University. I will be here from 12:00pm - 2:00pm PST (15 ET,20 UTC) to answer your questions…AMA! submitted by /u/AskScienceModerator [link] [comments]

What's happening in my brain when someone says something to me, then I ask "what?" and immediately realize I heard them perfectly in the first place? Posted: 21 Jun 2016 01:50 PM PDT submitted by /u/realandrei [link] [comments]

Is evolution guaranteed where there's life? Posted: 22 Jun 2016 06:07 AM PDT Recently I read a New York Times article saying that, if we use Drake's equation as a general guideline, then we should believe that it is extraordinarily likely that intelligent life besides ours has appeared at some point in our galaxy. The article failed to explain why we should assume that evolution occurs anywhere where life appears. Why should we assume this? Aren't there reasons to withhold this assumption? We have only seen how living organisms behave on earth, and their behavior here is no credible model for their behavior elsewhere. Maybe evolution is a necessary consequence of living organisms striving for survival, but how can we assume that life elsewhere would also strive for survival, as it does on earth? Even if it did and evolution followed, how can we assume that evolution's trajectory elsewhere would lead towards something like human intelligence? Why not just a bunch of highly specialized organisms - highly speciated, but nothing like rational and technological species. If we can't back up these assumptions, then isn't Drake's equation pretty unsubstantiated? submitted by /u/waitinround2d [link] [comments]

When talking about brain waves, what actually are these waves? Posted: 22 Jun 2016 12:55 AM PDT What are the waves representing? Is it simply a function of brain activity? Does activity occur in waves? If so, why does it occur in waves and not a steady stream? submitted by /u/UnclePutin [link] [comments]

The diagnosis rate of depression is 6.7% of adults, so why is it as a "disorder" if having the condition is not a statistical anomaly? Posted: 22 Jun 2016 03:21 AM PDT Is this a problem with our definition of depression? Our diagnosis rate? Why do we refer to depression as being "abnormal" when "normal" (not depressed) fails 95% confidence? submitted by /u/blackholymoly [link] [comments]

What makes Quantum mechanics and the General Theory of Relativity incompatible? Posted: 22 Jun 2016 02:08 AM PDT I am reading The Elegant Universe by Brian Green. Right at the beginning Brian says that Quantum mechanics and General Theory of Relativity aren't compatible with each other, ie, they both can't coexist under the same set of laws. But he never explains and details what's making it so. Can someone enlighten me where they clash? submitted by /u/antistar88 [link] [comments]

What is a lens flare and why does it happen? Posted: 22 Jun 2016 05:16 AM PDT Here's an example of what I'm talking about http://www.psdgraphics.com/file/lens-flare-effect.jpg submitted by /u/oddonesmishapenhead [link] [comments]

Why are 1, 3, 7, and 9 the only numbers whose multiples can end in any digit? Posted: 21 Jun 2016 06:58 PM PDT Obviously 1 can multiply into anything. Multiples of 7 can end in any digit 0 through 9 07 14 21 28 35 42 49 56 63 70 Same for 3 03 06 09 12 15 18 21 24 27 30 And 9 09 18 27 36 45 54 63 72 81 90 But 2, 4, 5, 6, and 8 won't do it. submitted by /u/_Username-Available [link] [comments]

What are meteorites made from? Posted: 22 Jun 2016 05:00 AM PDT Title pretty much explains it all, it's always interested me, like are they granite? Because surely that would imply they were formed volcanically, or are they just pure elements? submitted by /u/patienceandthyme [link] [comments]

Is there any material that is not a solid at absolute zero? Posted: 21 Jun 2016 03:24 PM PDT submitted by /u/harald705 [link] [comments]

If you exercise when it's hot outside, you certainly feel more tired, but do you actually burn more calories? Posted: 22 Jun 2016 05:39 AM PDT submitted by /u/nirvanna94 [link] [comments]

How does inhaling work? You're not creating a vacuum or something, right? Posted: 21 Jun 2016 07:40 PM PDT submitted by /u/kmaheynoway [link] [comments]

If the Dead Sea is 400m below sea level, would it be possible to refill it to sea level by simply building a canal to it from the Mediterranean? Posted: 21 Jun 2016 01:53 PM PDT submitted by /u/hoikarnage [link] [comments]

If two black holes spinning in opposite directions of each other were to come close to one another and eventually merge, what would happen to the event horizon before and after merging? Posted: 21 Jun 2016 02:21 PM PDT My buddy and I were talking about this in regards to the milky way and andromeda merging and what would happen if Sagittarius A and andromeda's black hole at the galactic core were to hypothetically merge with one another. So would the event horizon increase, decrease, or do some things that we simply don't know yet? submitted by /u/a-rabid-hamster [link] [comments]

Do gravitational waves get "red" shifted like light and radio waves do? Posted: 21 Jun 2016 09:47 AM PDT With improved instruments for Gravitational Wave Astronomy, it seems science will soon be able to listen in to ever distant black hole collisions and other similar events. I'm curious if there is any property of the gravitational distortion that is directly affected by expansion of the universe? Thank you. submitted by /u/BrightGene [link] [comments]

Are there objects far enough away from us that light they have emitted has never reached Earth, but will in the future? Or are all such objects traveling away from the Earth faster than the speed of light? Posted: 21 Jun 2016 08:32 PM PDT The universe is isotropic and expanding, so everything is moving away from everything else. Are there light-emitting objects far enough away from the Earth and moving fast enough that in the ~14 billion years of the universe's existence their light has never reached us? If there are, will that light ever reach us? Or is impossible based on the geometry of the universe? submitted by /u/pelzhaus [link] [comments]

How can the quality of a video deteriorate if it is uploaded, downloaded and re-uploaded to and from the same location? Posted: 21 Jun 2016 06:37 PM PDT This question comes from this post where he uploaded and downloaded and re-uploaded the same video 1000 times. My thinking is this: Let's say you export a video, and take the SHA1Sum of the exported file. (For my knowledge a SHA1Sum verifies that a file downloaded is the same as the source file.) Then you upload and download the file, and compare its SHA1Sum to the original SHA1Sum. I imagine that they would be the same, because the same file was uploaded and downloaded. Now if the process was repeated 1000 times, I still would think that the SHA1Sum's would be identical. I thought that maybe it was YouTubes processing of the video which deteriorated it over time causing a change in the SHA1Sum, so to exclude that factor, instead of uploading to youtube, what if it were uploaded to Dropbox, Google Drive, or even just another computer on the same network. What causes this video deterioration if the SHA1Sums do not change? submitted by /u/HiddenGhost14 [link] [comments]

An object in space gives off sound waves with the same amount of energy as light radiation from the Sun and at the same distance from Earth as the Sun. Would we be able to hear the sound on Earth? Posted: 21 Jun 2016 06:36 PM PDT Sorry if this doesn't make sense. It could help to read the inspiration for this submission, which was a recent comment on r/blind (last paragraph). submitted by /u/gelema5 [link] [comments]

How does a stem cell know in which way it has to specialize depending on its place in the embryo ? Posted: 21 Jun 2016 12:03 PM PDT Science books from high school told me it was because of its location. So yeah, kinda obvious, cells on the top become "head", cells on the bottom become "bottom". But which factor influence this? How does one cell knows it is "on the top" ? Maybe I am wrong about this, please correct me. submitted by /u/MrSydFloyd [link] [comments]

If I electrify the pan I am using for melting a chocolate bar, will it have any results the article mentions? Posted: 21 Jun 2016 01:53 PM PDT Here is the post with the article I refered in the title: https://www.reddit.com/r/science/comments/4p3rug/scientist_discovered_that_by_running_liquid/ It's actually a honest question and not a try on /r/askshittyscience. submitted by /u/Soudescolado [link] [comments]

Do we experience time dilation relative to the rest of the universe? If so, how does it affect us? Posted: 22 Jun 2016 12:23 AM PDT In Vsauce's most recent video, he said that relative to the Cosmic Background Radiation of the universe earth is traveling at approximately 2.1 million kilometers per hour. When I watched this, I was a little shocked at first, because that seemed really damn fast. So... What is the validity of this? If it's true, what affects does this have on astronomy and humanity? submitted by /u/anerdson [link] [comments]

Gas expands when heated. Gas cools when it expands. What gives? Posted: 21 Jun 2016 01:42 PM PDT It's been about a decade since I took AP chemistry...I can remember some things like "gas solubility in liquid increases as temperature of solvent decreases," but I can't remember why. It seems, intuitively, that if adding heat makes a gas expand, then an expanded gas should have more heat. What am I missing? submitted by /u/igottennispenis [link] [comments]

Would a empty hard disk weight differently than a full one? (considering both hard disks are identical) Posted: 22 Jun 2016 06:13 AM PDT submitted by /u/not_an_ottoman [link] [comments]

How to achieve a perpetual sunset? Posted: 21 Jun 2016 08:23 PM PDT Hello /r/askscience, I have a peculiar question for you. I'm a huge fan of sunsets, and was wondering if it was possible to catch one on land. And it isn't. But by plane it is, as you have to be traveling about 1000mph by jet. However is there such an altitude (or it may even be considered an orbit at some point) at which you could cruise at a comfortably slow speed and watch a perpetual sunset for a few hours at a time? submitted by /u/jacobyflynn [link] [comments]

You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google Inc., 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States

Hi Reddit, I’m Margaret Leinen, here to talk about the world’s oceans and how we observe them. Ask Me Anything!

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• Hi Reddit, I’m Margaret Leinen, here to talk about the world’s oceans and how we observe them. Ask Me Anything!
• Why does cheddar cheese crumble, but mozzarella is stringy and stretchy?
• Do young children who grow up bi-lingual initially assume they are just learning 1 language, or do they always know that they speak more than 1 language?
• When a light or sound wave hits a surface upon which it can reflect, it undergoes a phase change of pi. Why?
• If you fired a handgun from the ISS, pointing away from Earth, would it be able to escape Earth's gravitational pull?
• Why aren't balloons used as a platform for space launches?
• Is there a maximum speed at which a gas can escape through a hole? What affects it?
• Black holes bend space so that light doesn't have a "path" out. How does more matter enter a black hole?
• If water boils in a vacuum, what happens if there is not much space for the water to expand into (e.g. the airless volume inside a container is only twice the size of the volume of water as a liquid)?
• Does increasing the pressure of a gas in a container (and thus increasing the gas's density) decrease the speed of light through it?
• How do electronics in satellites not get effected by the Earth's magnetic field? Does the field affect the orbit speed/direction due to the satellite being made of metal?
• Why is brain size relevant in comparing interspecies intelligence but not intraspecies intelligence?
• if 'mass is confined energy', and energy is just a concept that help us in dealing with physics, what does the first phrase mean ??
• What were humans when the asteroid hit?
• Are we anywhere near making nuclear fusion produce more energy than it consumes?
• Is there any not-yet-feasible but theoretically sound experiment that would determine topology of the universe?
• Can all combinations of sounds be replaced by a sound of a single frequency?
• I saw a picture of an Owl nest (Link Inside) basically made out of lemmings. Is this normal behavior and why would an animal make a nest of other animals?
• What is the advantage of having five, rather than four or six, fingers?
• How is information encoded between the eye and the brain?

Hi Reddit, I’m Margaret Leinen, here to talk about the world’s oceans and how we observe them. Ask Me Anything! Posted: 21 Jun 2016 05:32 AM PDT I'm the president (http://about.agu.org/president/) of the American Geophysical Union, the world's leading organization of earth and space scientists, and I'm also the director of Scripps Institution of Oceanography (https://scripps.ucsd.edu/) at UC San Diego (http://www.ucsd.edu/), which has a global focus on understanding and protecting the planet through ocean, earth, and atmospheric explorations. The oceans cover more than 70 percent of the planet and hold the key to many critical challenges facing science and society, from sustainably feeding human populations to addressing the impacts of climate change to protecting vulnerable marine species. One of the cornerstone methods of keeping tabs on the oceans is through innovative tools and technologies to monitor them. At Scripps Oceanography we contribute to several ocean observation systems and networks that relay critical data about the seas and how they are changing. These include networks just off our populated coastlines (Southern California Coastal Ocean Observing System, (http://www.sccoos.org/)) for applications as diverse as marine operations, coastal hazards, and ecosystems, to far out at sea where it's not easy to access information (Argo, (http://argo.ucsd.edu/)) to help us understand phenomena such as El Niños and ocean warming. I look forward to answering your questions about ocean observations between 12 and 1 EST on Tuesday, 21 June! Ask Me Anything! submitted by /u/AmGeophysicalU-AMA [link] [comments]

Why does cheddar cheese crumble, but mozzarella is stringy and stretchy? Posted: 20 Jun 2016 07:46 PM PDT Did a quick google, didnt find anything. Edit: probably flaired wrong. Sorry mods, not sure where it goes submitted by /u/AccidentallyTheCable [link] [comments]

Do young children who grow up bi-lingual initially assume they are just learning 1 language, or do they always know that they speak more than 1 language? Posted: 20 Jun 2016 08:47 PM PDT I recently met a child who spoke both Russian and English. However, she just used the languages interchangably and could alternate words in a sentence between the two languages. I grew up bi-lingual but I knew I only spoke one language with my grandparents, and English with my parents. So does this child who creates sentences in 2 languages really know that she is speaking 2 languages? Or does she just think that there are more than just 1 word per item she is refering to, and uses them interchangably? submitted by /u/nopeitynopenop [link] [comments]

When a light or sound wave hits a surface upon which it can reflect, it undergoes a phase change of pi. Why? Posted: 21 Jun 2016 02:09 AM PDT Why doesn't it undergo a path change of half a wavelength instead? submitted by /u/Ohowun [link] [comments]

If you fired a handgun from the ISS, pointing away from Earth, would it be able to escape Earth's gravitational pull? Posted: 20 Jun 2016 08:25 PM PDT Title. My mates and I were discussing bullet physics in space and this scenario came up. In addition to the primary question, would you actually be able to fire a gun in space? We surmised that the atmosphere within the bullet would sustain the ignition to fire the weapon, but we're tired, stupid, and we need real answers. submitted by /u/JP20Boss [link] [comments]

Why aren't balloons used as a platform for space launches? Posted: 20 Jun 2016 08:38 PM PDT Obviously a balloon couldn't make it to space, but could one not be used to carry a launch vehicle the first 30km or so, allowing it to launch from above the thickest part of the atmosphere? Even if it didn't mean an increase in payload, I imagine a balloon launch would be significantly cheaper than all the hardware/fuel required for a launch from the ground. submitted by /u/lesabre98 [link] [comments]

Is there a maximum speed at which a gas can escape through a hole? What affects it? Posted: 20 Jun 2016 08:29 PM PDT If I have an indestructible un-shape-changeable ^(I hope someone could provide me with a word that would fit that better) balloon and I filled it at 1 psi, then 2 psi, then 3 psi ... up to infinity, would there be a maximum speed at which gases could escape? submitted by /u/SellMeAllYourKarma [link] [comments]

Black holes bend space so that light doesn't have a "path" out. How does more matter enter a black hole? Posted: 20 Jun 2016 11:33 AM PDT This is very confusing to me. As I understand it, the reason light can't escape a black hole is because the gravity of the black hole has bent space so much that there isn't an path that light could take that would lead out of the black hole. If that's true, wouldn't a black hole somehow segregated from the rest of space? How does this even work? submitted by /u/n1nj4d00m [link] [comments]

If water boils in a vacuum, what happens if there is not much space for the water to expand into (e.g. the airless volume inside a container is only twice the size of the volume of water as a liquid)? Posted: 20 Jun 2016 12:05 PM PDT I was trying to image what would happen if I had some water (say a liter) inside an airtight container and it filled the space. If I could draw a plunger and expand the space to 2 liters, but no air could get in, and the container would resist the pressure, what would happen to the water. Would it become a basically a less dense liquid spread throughout the 2 liter space)? submitted by /u/efficiens [link] [comments]

Does increasing the pressure of a gas in a container (and thus increasing the gas's density) decrease the speed of light through it? Posted: 21 Jun 2016 04:28 AM PDT submitted by /u/Menaus42 [link] [comments]

How do electronics in satellites not get effected by the Earth's magnetic field? Does the field affect the orbit speed/direction due to the satellite being made of metal? Posted: 20 Jun 2016 08:41 PM PDT submitted by /u/Blade2277 [link] [comments]

Why is brain size relevant in comparing interspecies intelligence but not intraspecies intelligence? Posted: 20 Jun 2016 03:35 PM PDT Why is it that brain volume is considered a relevant factor in estimating the approximate difference in intelligence in early and late hominid species but between individuals or groups or modern humans? submitted by /u/READERmii [link] [comments]

if 'mass is confined energy', and energy is just a concept that help us in dealing with physics, what does the first phrase mean ?? Posted: 20 Jun 2016 04:52 PM PDT submitted by /u/Moon_ire [link] [comments]

What were humans when the asteroid hit? Posted: 20 Jun 2016 04:28 PM PDT I.e., 65 million years ago, what (ape) ancestor(s) survived that extinction to become humans? submitted by /u/Biuku [link] [comments]

Are we anywhere near making nuclear fusion produce more energy than it consumes? Posted: 20 Jun 2016 01:19 PM PDT At least from what i have understood, that current ones aren't very effective. submitted by /u/Thermawrench [link] [comments]

Is there any not-yet-feasible but theoretically sound experiment that would determine topology of the universe? Posted: 20 Jun 2016 10:01 AM PDT Or is there a fundamental problem preventing one from observing the topology of the spacetime he's in? submitted by /u/hardex [link] [comments]

Can all combinations of sounds be replaced by a sound of a single frequency? Posted: 20 Jun 2016 09:43 AM PDT I know that a sound is determined by its amplitude (loudness), frequency (pitch), and harmonics. Suppose I play 2 different notes on the keyboard. The sound wave pattern that I get, can I play a sound at a specific frequency which would sound the same as the 2 combined? Should this frequency also be present on the keyboard? I guess what I'm asking is do sounds of different frequencies combine in any form to create new frequencies like light? Or are they only recreatable as a combination of multiple different sounds? Also, side question: all notes on a keyboard have a fixed frequency. Do the different preset tunes only differentiate in harmonics, or is it something else? submitted by /u/athousandwordss [link] [comments]

I saw a picture of an Owl nest (Link Inside) basically made out of lemmings. Is this normal behavior and why would an animal make a nest of other animals? Posted: 20 Jun 2016 01:04 PM PDT http://imgur.com/rfo4QTD submitted by /u/WadeWilsonforPope [link] [comments]

What is the advantage of having five, rather than four or six, fingers? Posted: 20 Jun 2016 04:33 AM PDT Why do humans have five fingers (and toes) instead of any other number of fingers (and toes) submitted by /u/Edgele55Placebo [link] [comments]

How is information encoded between the eye and the brain? Posted: 20 Jun 2016 04:26 AM PDT Taking a very simplistic and potentially naive view of the eye, it takes in light (or "information") which stimulates rods and comes which are on the retina. This information is then transmitted along the optic nerve to the brain. This information needs to be encoded in some form - do we know how it is encoded? submitted by /u/pugl33t [link] [comments]

You are subscribed to email updates from AskScience: Got Questions? Get Answers.. To stop receiving these emails, you may unsubscribe now.	Email delivery powered by Google
Google Inc., 1600 Amphitheatre Parkway, Mountain View, CA 94043, United States

AskScience AMA Series: I'm astronaut Leland Melvin, space shuttle traveler and explorer. Ask My Anything!

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• AskScience AMA Series: I'm astronaut Leland Melvin, space shuttle traveler and explorer. Ask My Anything!
• Drinking water from natural sources and it needing to be boiled?
• Can I get an educated guess on what the creature might be that was found on Google Earth new Deception Island?
• Why are emitted Photons in a Quantum Dot Laser coherent?
• During normal thought, does that "inner voice" actually create vibrations on your vocal cords?
• How can one prove the Laws of Conservation?
• Other than humans, are there any known species on Earth that have increased their natural lifespans?
• The paradox of calculus - zero but not zero: is there a good explanation?
• Anything Smaller Than a Sub-Atomic Particle?
• how carbon and gamma rays interact?
• Is the sheer size of the yellowstone magma chamber keeping it from erupting?
• Can we determine animal behavior solely from fossil records?
• What geological evidence do we have to prove that ice ages are cyclical??
• Is there a material that allows movement in one direction but stops it in the other depending on how it is applied?
• Can wind patterns cancel each other out?
• Is it theoretically possible to keep a heavy element stable by trapping it in graphene, and possibly within a geometric arrangement of other atoms whose proximity 'force it' into stability?
• Why do nuclear reactors need a steam turbine to generate electricity? Why can't we just directly convert the thermal energy into electricity?
• Is there a typical bond length cutoff for hydrogen bonding?
• How are the amplitude and frequency of gravitational waves related to the source of said waves?
• Are we 100% sure that there isnt a stronger degeneracy pressure that would prevent a singularity from forming?
• What happens to tectonic plates when continents move?
• Relativistic space travel thought experiment: Time dilation, how does it work?
• Why is the interstellar medium made of hydrogen atoms and not H2 gas?
• Do black holes move through space? [Physics]

AskScience AMA Series: I'm astronaut Leland Melvin, space shuttle traveler and explorer. Ask My Anything! Posted: 20 Jun 2016 04:57 AM PDT Hi everyone. I'm Astronaut Leland Melvin, a space shuttle traveler, explorer and STEAM (Science, Technology, Engineering, Art, and Mathematics) education promoter. This summer I'm featured on Science Channel's new series, HOW TO BUILD...EVERYTHING premiering on Wednesday, June 22 at 10PM. I will be here starting around 2 PM ET to answer your questions. Ask Me Anything! submitted by /u/AskScienceModerator [link] [comments]

Drinking water from natural sources and it needing to be boiled? Posted: 20 Jun 2016 01:37 AM PDT I watch quite a lot of surviving in the wild type programs and one thing that constantly puzzles me is the idea humans can't drink from natural water sources unless the water is boiled. I find it hard to believe our ancestors did this when we were hunter gathers and it seems odd to me that all other animals seem to have no issues drinking from whatever water source they can find. So what's the explanation? Would we actually be fine in a lot of cases and people are just being over cautious? Is it a matter of us just not having the exposure to the various bugs that might be found in such water? If say we had been drinking it all our lives would we be fine with it? submitted by /u/dvb70 [link] [comments]

Can I get an educated guess on what the creature might be that was found on Google Earth new Deception Island? Posted: 20 Jun 2016 06:50 AM PDT Video: https://www.youtube.com/watch?v=F-WZ7CCpsis Is this some sort of magical sea creature or something from the deep? Or is it most likely something completely explainable that was blown out of proportion by the internet? Detailed reasoning would be interesting and helpful. submitted by /u/MagnanimousCannabis [link] [comments]

Why are emitted Photons in a Quantum Dot Laser coherent? Posted: 20 Jun 2016 03:39 AM PDT Hello Guys, I know how spontaneous emission and stimulated emission in classic laser works. With the three energy levels of the atom, the atom in the excited state and whatsoever. I know how Quantum Dots work. Small crystals below the Bohr radius of the atom. I know (kind of) why the emitted Photons of a Quantum Dot has a wavelength dependent of the size of the Quantum Dot. What I don't understand is, why are the emitted Photons in a Semiconductor Quantum Dot Laser coherent? Coherent means in phase with each other and the same wavelength, right? It is understandable for me with the stimulated emission in a normal Laser, but i don't get how it works in a Quantum Dot Laser. It would be cool if someone is able to explain this to me. I need to know this :P submitted by /u/Activehannes [link] [comments]

During normal thought, does that "inner voice" actually create vibrations on your vocal cords? Posted: 19 Jun 2016 04:39 PM PDT submitted by /u/3findthrow [link] [comments]

How can one prove the Laws of Conservation? Posted: 20 Jun 2016 04:14 AM PDT Of mass, energy, etc? submitted by /u/hmpher [link] [comments]

Other than humans, are there any known species on Earth that have increased their natural lifespans? Posted: 19 Jun 2016 04:38 PM PDT submitted by /u/ChocoScoots [link] [comments]

The paradox of calculus - zero but not zero: is there a good explanation? Posted: 19 Jun 2016 09:58 PM PDT Here's what's always bothered me about calculus and real analysis. I understand how the limit as delta x approaches zero, the slope gets infinitely accurate. But delta x cannot be zero, or else the function is undefined. I see how you can factor and get a value that isn't defined, such as how the derivative of x2 simplifies to 2x+h and then the h term is treated as exactly zero. But we still treat delta x is zero even though it can't be zero! For example, with the tangent line, Leibniz defined it as two points that are infinitely close together - this makes sense but it seems that modern calculus and standard analysis thew this idea out the window. We now define the tangent as the line touching at one point with the same instantaneous rate of change at that point. But if it touches at one point, then that means delta x is zero and the function is actually undefined! In summary: I can't see how we don't just say the function's slope is tending to "a" as the distance becomes infinitely small. We say it's exactly "a". We say it touches at exactly one point. But the idea of exactness and the tangent line instead of an infinitely accurate secant line makes me frustrated because there's a paradox I can't get over. Is there a good explanation as to how I can understand why we can say what we do without it really being a contradiction? submitted by /u/dog-damnit [link] [comments]

Anything Smaller Than a Sub-Atomic Particle? Posted: 20 Jun 2016 07:40 AM PDT So, I was wondering, is there anything with mass that could be smaller than a sub-atomic particle, like a quark or gluon? I would imagine that the smallest piece of matter physically possible would be the Planck length, but I'm not sure if that's really a possibility. submitted by /u/PlatinumDV [link] [comments]

how carbon and gamma rays interact? Posted: 20 Jun 2016 06:55 AM PDT Hello, I have a series of questions but I will start with this one and a question leading from it here first. So here we go. 1) My first question is about gamma ray and carbon interaction, If I was to blast gamma rays at carbon what thickness would be nessesery to lower the radiation to safe levels. 1.2) are there any interactions that would effect the carbon from gamma rays? heating or changes in structure? or would they just pass through and deflect? and leading from that 2) Would the shape of the material gratly effect the interactions? I have in mind to have a conal or triangular shape. I know it would increase the thicknes on a direct angle of attack. That is all for now. Thanks in advance. submitted by /u/nibs123 [link] [comments]

Is the sheer size of the yellowstone magma chamber keeping it from erupting? Posted: 19 Jun 2016 05:08 PM PDT I think it doesn't matter how big it is, it WILL erupt. But my brother thinks that maybe the sheer size of the chamber is keeping it from erupting. He thinks that the amount of energy required to erupt it is too much at this point. submitted by /u/Ogrebreath [link] [comments]

Can we determine animal behavior solely from fossil records? Posted: 20 Jun 2016 05:21 AM PDT For example, would we know hippos are so territorial and aggressive if the only evidence we had of them was from fossil records? submitted by /u/Kiroway66 [link] [comments]

What geological evidence do we have to prove that ice ages are cyclical?? Posted: 19 Jun 2016 06:11 PM PDT submitted by /u/silversnap [link] [comments]

Is there a material that allows movement in one direction but stops it in the other depending on how it is applied? Posted: 19 Jun 2016 04:30 PM PDT submitted by /u/UltimateHawkpie [link] [comments]

Can wind patterns cancel each other out? Posted: 19 Jun 2016 05:18 PM PDT I was just looking at >this site< and I see in the middle of the hellfire that is the northern Mexico there is one point (green circle) where all the wind systems seem to be targetted at. ALL wind. This doesn't seem right. Google maps location Screenshot Is there some sort of cancellation effect? Is this map simply incorrect? Is the Maw of Cthulhu opening in the desert and sucking the energy of the planet dry? submitted by /u/opus-thirteen [link] [comments]

Is it theoretically possible to keep a heavy element stable by trapping it in graphene, and possibly within a geometric arrangement of other atoms whose proximity 'force it' into stability? Posted: 20 Jun 2016 07:06 AM PDT submitted by /u/blue-dot [link] [comments]

Why do nuclear reactors need a steam turbine to generate electricity? Why can't we just directly convert the thermal energy into electricity? Posted: 19 Jun 2016 09:31 AM PDT submitted by /u/nottoodrunk [link] [comments]

Is there a typical bond length cutoff for hydrogen bonding? Posted: 20 Jun 2016 06:03 AM PDT I am wondering about heuristics for quick evaluation of expected hydrogen bonding of a structure by inspection. Is there a rule of thumb judging by bond distance only to say whether or not you probably can expect there is significant hydrogen bonding in the solid state? Especially for these: N = N ••• H O = N ••• H I am doing DFT studies of NMR parameters in some molecular crystals containing C, H, N, O. I am interested in how hydrogen bonding effects the electronic structure (and hence the magnetic resonance) near Nitrogens. submitted by /u/AltoidNerd [link] [comments]

How are the amplitude and frequency of gravitational waves related to the source of said waves? Posted: 19 Jun 2016 08:08 PM PDT If a body produces gravitational waves, does the amplitude increase with the mass of the body? What about the frequency? Could especially high frequency gravitational waves bring two points in space much closer together from the viewpoint of a higher spatial dimension than the three we perceive in spacetime? submitted by /u/DickJohnsonPI [link] [comments]

Are we 100% sure that there isnt a stronger degeneracy pressure that would prevent a singularity from forming? Posted: 20 Jun 2016 02:00 AM PDT submitted by /u/sourc3original [link] [comments]

What happens to tectonic plates when continents move? Posted: 19 Jun 2016 05:23 PM PDT I understand that continents move BECAUSE tectonic plates exist. But I don't understand how is that tectonic plates make continents move, I can see why earthquakes happen and why mountains arise in Earth history. But considering that tectonic plates are very well embedded, I just don't understand what happens with them when continents move. Or how would they move across such a distance. For example, in this speculative video of continents moving, I don't know what's happening with the plates beneath the ocean. I've found several videos showing how continents evolved from Pangea to their current place, and speculative videos of how continents will evolve to form Pangea Ultima, but I've never found a video of how tectonic plates evolved from Pangea to their current place (or how they will behave to form Pangea Ultima). submitted by /u/Dimakhaerus [link] [comments]

Relativistic space travel thought experiment: Time dilation, how does it work? Posted: 19 Jun 2016 01:13 PM PDT So I have some difficulties understanding the "real world" implications of special relativity time dilation. Most examples you find on the internet deal with one observer at rest and one observer moving past the first tangentially at near light speed. They also all deal with magical telescopes that ignore redshifting and the actual distances traveled. This of course doesn't take into account how it'd look like for an observer at rest at the start or end of the journey so that the crew moves directly away from/at them respectively. So the spaceship Z by virtue of the WonderDrive(TM) is able to accelerate to 99.999X% of light speed within a day without disintegrating. This is used to make the trip from Earth to Proxima Centauri that is exactly 4 light years away in this experiment. Now what I am interested in is what the observers named Earth, Proxima and Spaceship-Z see in their respective frames. The predictions I'd make is what is so paradoxical to me since in my opinion point 2 and 3 contradict the usual examples when taking account the actual propagation of the light waves: Earth sees a massively redshifted Spaceship-Z that appears to accelerate progressively much slower than it actually does due to length contraction. It also seems to slow down during its journey which it appears to have completed after 8 years. During that time the redshifted images observed showed the crew at a near standstill. This should be analogous to the usual examples. Spaceship-Z sees a massively redshifted Earth with clocks moving at the same rate at Spaceship-Z's. They themselves perceive their journey to take, say, 1 hour. The distance from Earth to Proxima is massively contracted for them. Proxima doesn't see anything for almost 4 years in the frame at rest relative to Earth. Then in the end they see a flash of massively blueshifted light from Spaceship-Z whose clock looks on the one hand slowed down according to the time dilation experienced by Spaceship-Z, on the other hand sped up immensely because the light that is emitted at the start of the journey reaches Proxima only seconds before the ships arrival, like a bow wave. During travel its own light emissions appear to move at c in relation to Spaceship-Z because in their back the distance is contracted and in the front the distance covered by the photons emitted and the spaceship is in line with the massively dilated time. So I am sure a lot of my assumptions here are wrong because I adhere to classical mechanics wave propagation too much. It'd be nice if an astrophysicist could drop in and explain to me why my hypotheses 2 and 3 are at odds with the notion that Spaceship Z should in turn see time slowed at Proxima and Earth at the same rate as they should see it slowed in the Spaceship. submitted by /u/searingsky [link] [comments]

Why is the interstellar medium made of hydrogen atoms and not H2 gas? Posted: 19 Jun 2016 01:13 PM PDT From Wikipedia: Approximately 70% of the mass of the interstellar medium consists of lone hydrogen atoms; most of the remainder consists of helium atoms. Given enough time and collisions, why doesn't the hydrogen atoms form diatomic hydrogen gas? submitted by /u/TheSecretNothingness [link] [comments]

Do black holes move through space? [Physics] Posted: 19 Jun 2016 04:09 PM PDT I would imagine they would, but I'm curious if something like a black hole would still be bound by inertia and velocity. Some part of me wants to imagine them as essentially a hole in space/ time. Though they obviously produce a gravitational pull to other objects, are they, themselves, also subject to these forces? Apologies if my question has an obvious answer. My background is in chemistry and biology, so although I have an interest in astrophysics, my understanding of physics on an astronomical scale is limited. submitted by /u/zeronyx [link] [comments]

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