| Why do we have two of certain organs while only one of certain others? What would an evolutionary reason to reject two hearts to one lung or one kidney to two livers for example be? Posted: 09 Dec 2016 10:51 PM PST |
| If someone is above the clouds (ex: atop a mountain) is it still possible to be struck by lightning? Posted: 09 Dec 2016 12:25 PM PST |
| Why isn't CO2 visible? Posted: 10 Dec 2016 12:00 AM PST I happened across a absorption spectrum of CO2 which included the very end of the visible spectrum. It seems to show CO2 absorbs light in the 630-700 nm wavelength, at least somewhat. I'm curious why, if CO2 seems to absorb some visible light, high concentrations of it are not visible as bluish/cyan gas (white light removing the deep reds). Is there something I am missing here? What led me to this was an interest in replicating the sort of things shown here or here. These all seem to use mid wave IR and a narrow bandpass filter. I would imagine that if a narrow bandpass filter around 650 nm on a regular camera would let you see CO2, they would have done that instead. But I don't see why it wouldn't work. EDIT: As Shookfoot notes below, the units on the graph are wavenumber, not nanometers wavelength. As such, the absorption isn't in the visible spectrum at all. submitted by /u/hansn [link] [comments] |
| Is a black hole hot or cold? Posted: 09 Dec 2016 05:25 PM PST Given that a black hole's singularity is an infinitely dense object (theoretically) is it infinitely hot? Or because it can redirect all energy towards itself would it be cold as it could not radiate energy? submitted by /u/Spankmewithataco [link] [comments] |
| With amber playing such an important role in the fossil record, I can't help wondering why big globs of resin were seemingly so abundant during ancient eras. Can someone explain? Posted: 09 Dec 2016 11:15 AM PST |
| How can we estimate a quantifiable amount of mass to exist in the universe, and speculate the universe to be infinite simultaneously? Posted: 10 Dec 2016 07:05 AM PST When I Google "how much mass is in the universe", I get this answer: Now, the size of the observable universe is about 14 billion light years, and using the above value of density gives you a mass (dark and luminous matter) of about 3 x 1055 g, which is roughly 25 billion galaxies the size of the Milky Way. How can we say this, yet believe that the universe is infinite? Does an infinite universe not imply infinite matter & time & space also? Or am I thinking of this wrong- are these actually conflicting theories (an amount of mass versus infinite mass)? submitted by /u/JOHANSENATOR [link] [comments] |
| Can an atom be more stable in a molecule? Posted: 09 Dec 2016 11:37 PM PST Four highly unstable atomic elements Nihonium (Nh), Moscovium (Mc), Tennessine (Ts), and Oganesson (Og) with half-lives of seconds or smaller were just named, and there is already speculation on their molecular possibilities. Can bonds with neighboring atoms and electrons keep an atom from decaying as fast as it would alone? submitted by /u/Drakonic [link] [comments] |
| Can a planet have a non-rocky moon (i.e. gas)? Posted: 09 Dec 2016 04:14 PM PST |
| Does the Sun ever get hotter or cooler at different times of the year? Posted: 10 Dec 2016 07:27 AM PST |
| Is it possible to represent the exact instant the universe began using everyday time notation? ie "3:43:11 am on Wednesday, March the third, 7,772,874,665 BC"? Posted: 10 Dec 2016 05:53 AM PST |
| What would happen if you mixed all the chemical elements in the Ask Science logo? Posted: 09 Dec 2016 08:42 PM PST |
| What happens when a hypothetical black hole would exist that's so big that metric expansion becomes noticeable across it's diameter? Would this affect its Schwarzschild radius? It's temperature? Anything else? Posted: 09 Dec 2016 06:31 PM PST |
| What causes degradation of vision in astronauts who are in space for longer than 6 months? Posted: 09 Dec 2016 10:07 PM PST I heard that some astronauts were coming back to Earth with impaired vision. Sometimes going from 20/20 vision to 20/100. I theorize that this is due to a lack of use in viewing/focusing on object details at distances greater than 2-3m. When going for a daily stroll you view objects that are anywhere from 25cm up to 3km away. Your eyes are constantly being stimulated to make massive fluctuations in viewing distance and focusing in on the detail. In outer space, I imagine that your eyes don't get too much practice in viewing objects further than maybe 10 feet away at any given time. This leaves a huge gap in exercising your eyes on anything with a distance greater than a few feet. You could say that looking at the Earth exercise enough; but because human eyes cannot interpret that distance and due to it being outside of the flexible range of the lens in the human eye. It shows the earth as a relatively flat surface and is unable to show the planet in much detail and still leaves out the viewing distances of greater than 3m but less than 250km To fix this, there would need to be a tool or method of exercising the eyes of astronauts on a daily basis to slow the decay of vision. I understand that MRI scans have shown that the eyes of astronauts are flatter with swollen optic nerves, but I believe this to be due to a lack of muscle use in the eyes. submitted by /u/BlackWidowSpider [link] [comments] |
| How much does the strength of rope increase by braiding? Posted: 10 Dec 2016 01:50 AM PST |
| Can I use resonant frequency to crack ice? Posted: 09 Dec 2016 05:02 PM PST In other words, would an oscillating harmonic force be sufficient enough to crack and separate compact snow/ice on a metal pole or driveway? Thanks! submitted by /u/KTong94 [link] [comments] |
| How can you know when the Aurora Borealis will be be visible? Posted: 09 Dec 2016 06:20 PM PST I have a bucket list trip scheduled to Ivalo, Finland at the end of December to see the Northern Lights. Is there any way to know if they will be visible? submitted by /u/amttaylor [link] [comments] |
| What does actual economic research say about ways to achieve a high amount of sustained growth? Posted: 09 Dec 2016 11:56 AM PST |
| Why is blue light the hardest colour of light to focus our eyes on? Posted: 09 Dec 2016 09:25 AM PST My robotics teacher mentioned that blue LEDs are used in keyboards and other indicator lights, as it's the hardest colour to focus on and we don't pay much attention to it. Googling around has verified that blue is hard to focus on but I can't find any credible research talking about it or verifying it, so is it the hardest colour to focus on and if so, why? https://www.reference.com/science/hardest-color-see-d53b847eb1eeff5e# Is the most credible source I've found, but all of the links it references are dead. submitted by /u/TestPostPleaseIgnore [link] [comments] |
| How are tire treads designed? Posted: 09 Dec 2016 05:46 PM PST I learned about coefficients of friction in college but it can't be that simple, right? Does the tread pattern increase friction or is it more about redirecting water and dirt? submitted by /u/Angrybagel [link] [comments] |
| Does there exist a chart or diagram which visually shows that the faster an object moves in a spacial dimension, the slower it moves in the time dimension? Posted: 09 Dec 2016 05:41 PM PST Special and General Relativity say that as a massive object's velocity increases through a spacial dimension, its velocity through the time dimension decreases. I imagine that it would be fairly easy to chart the relationship on a graph, but I can't find one that does this. I remember once seeing a demonstration that all objects always move at c through spacetime, but an object can only move at c through spacial dimensions if its velocity through time is zero (i.e. it has no mass). An object with mass always has some non-zero velocity through time, and so can never reach c in spacial dimensions. In other words, it was something like, "an object's total velocity (c) = the object's velocity in space + the object's velocity in time." Could somebody link a graph explaining the relationship between an object's velocity in space and it's velocity in time, and how those two numbers are related to c? Or, if you're feeling particularly generous, could you make one yourself? I'm hoping for an animated graph, but i understand that that may be asking a lot. Thanks very much! submitted by /u/non-troll_account [link] [comments] |
| Where do deepsea anglerfish get their bioluminescent bacteria? Posted: 09 Dec 2016 11:45 AM PST I learned that deepsea anglerfish commonly use bioluminescent bacteria to light up their lures. But where do the anglers get that bacteria from? submitted by /u/xXHacknslasHXx [link] [comments] |
| Why does drinking alcohol lead to drunkenness? Posted: 09 Dec 2016 10:16 PM PST |
| What's happening at the molecular level to cause the colour change during titration? Posted: 09 Dec 2016 10:14 PM PST Asking this due to the recent why is water blue question. I do various titrations at work to ensure our process water is within spec. I will take our M-alkalinity test as the example since I've noticed a variation. Normally, when I titrate with our M Indicator (60-100% Isopropanol/1-5% Methanol) it will start off blue when M-alk is present with the endpoint being orange. Now I've noticed when the water has higher than normal levels of free Cl2 the endpoint will be green-yellow. The different colour for the endpoint has not affected the results. 250 ppm M-alk /w 0.13 ppm Free Cl2 & 250 ppm M-alk /w 2.18 ppm Free Cl2 Why do I see orange with low levels of free Cl2 and green-yellow with high levels of free Cl2? submitted by /u/Ristake [link] [comments] |
