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Wednesday, September 6, 2017

When a storm like Irma is at sea, what's happening below the surface?

When a storm like Irma is at sea, what's happening below the surface?


When a storm like Irma is at sea, what's happening below the surface?

Posted: 05 Sep 2017 08:08 PM PDT

How is the biosphere effected? Do fish just swim deeper and go about their regular life?

submitted by /u/DrJawn
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If you were to randomly find a playing card on the floor every day, how many days would it take to find a full deck?

Posted: 05 Sep 2017 09:25 AM PDT

The post from front page had me wondering. If you were to actually find a playing card on the floor every day, how long would it take to find all 52? Yes, day 1, you are sure not to find any duplicates, but as days pass, the likelihood of you finding a random card are decreased. By the time you reach the 30th card, there is a 22/52 chance of finding a new card. By the time you are looking for the last card, it is 1/52. I can't imagine this would be an easy task!

submitted by /u/Eddie_shoes
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Aside from Pu-238, what other sources of power could be used for deep space satellites?

Posted: 06 Sep 2017 06:35 AM PDT

I know Pu-238 was used by numerous satellites like Cassini and Voyager, but is there any other nuclear power source with a similarly long half-life? Po-210 would seem to be a possible substitute, but it's half-life is too short.

submitted by /u/7spade
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It is said the theoretical maximum sustainable wind speed in a hurricane is around 200mph. Why?

Posted: 05 Sep 2017 02:01 PM PDT

While there might be spikes above that, it is said that the theoretical maximum speed of wind, that a hurricane can keep up sustainably, is around 200mph. This is what Hurricane Irma is approaching towards. Why is that so?

submitted by /u/hdsjulian
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Why do larger elements have more neutrons in comparison to their protons?

Posted: 06 Sep 2017 07:18 AM PDT

Why do Ammonites seem to be the most common fossil, and why are they referenced so often to the Cretaceous–Paleogene extinction event, compared to other species who went extinct?

Posted: 06 Sep 2017 02:02 AM PDT

Why can't quarks exist as separate individual particles?

Posted: 05 Sep 2017 04:01 PM PDT

Im reading a physics book and the author just wrote the above argument with no explanation/ reference to some research on the subject as a basis. As if this was a given. I demand an explanation!

submitted by /u/Hashanadom
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How do scientists measure extreme temperatures?

Posted: 06 Sep 2017 12:55 AM PDT

E.g. the melting point of steel or near absolute zero. I'm pretty sure a regular thermometer wouldn't cut it.

submitted by /u/TheWonderworks
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Ask Anything Wednesday - Biology, Chemistry, Neuroscience, Medicine, Psychology

Posted: 06 Sep 2017 08:06 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Biology, Chemistry, Neuroscience, Medicine, Psychology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions.

The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here.

Ask away!

submitted by /u/AutoModerator
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Why does the European model for hurricane forecasts outperform the American model by such a large degree?

Posted: 05 Sep 2017 03:31 PM PDT

With the recent Hurricane Harvey hitting the United States in Texas, the American HMON model showed Harvey heading over Mexico, while the European model's prediction was very close to the actual path. Why is the American model so far behind?

Article for reference: https://arstechnica.com/science/2017/09/at-times-during-harvey-the-european-model-outperformed-humans/

submitted by /u/how_do_i_land
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How do all-purpose cleaners work?

Posted: 05 Sep 2017 05:11 PM PDT

I have a bottle here that lists several ingredients including: decyl glucoside, sodium citrate, glycerin, and a lot of natural oils. How do these ingredients actually clean a surface?

submitted by /u/mpblizzard
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How does being struck by lightning and surviving affect the survivor's physiology?

Posted: 05 Sep 2017 03:42 PM PDT

I've heard several stories of people being struck by lightning and surviving. In some cases, the same person was struck more than once at a different time. How does a lightning strike affect the body of survivors? Does it have any long standing effects that can be seen years after?

submitted by /u/AbruptBiblicalSword
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How does a radar measure a rotational speed of a baseball?

Posted: 05 Sep 2017 09:41 PM PDT

Start Speed: 88.3 mph Spin Rate: 1710.4 rpm

You can easily see these kinds of stats in baseball forums.
How do you measure a spin rate of a ball?

submitted by /u/skchyou
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How do trees know what time of year it is for defoliation?

Posted: 05 Sep 2017 03:46 PM PDT

I always thought it was something like hibernation, or if they are on a schedule? Thanks for answering!

submitted by /u/destroydadestroy
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Are there tectonic plates on Mars?

Posted: 05 Sep 2017 07:39 PM PDT

Earth's mountains and volcanoes are formed by tectonic plate collisions (at least, that's my basic understanding of it). So, is this the case on Mars? Does Mars have earthquakes (or, maybe call them marsquakes)? What about the volcanoes on Mars? Are there any, and if so, what are they like? Are the igneous rocks formed by those volcanoes similar to those on Earth? Also, what about Mercury and Venus? What do we know about those planets?

submitted by /u/caezium
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How do rocket scientists know what velocity is needed to enter the orbit of bodies other than Earth?

Posted: 05 Sep 2017 07:47 PM PDT

I'm been bingeing "Space Race" stuff lately and I think I can comprehend how we calculated the velocity required to enter orbit above Earth. I don't understand how we made the calculations to have a spacecraft enter orbit over a body that humanity has not set foot on.

What kinds of data were used to calculate velocities to enter orbit above bodies such as Jupiter.

I thank you in advance for any responses.

submitted by /u/kufunuguh
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How small could an aneutronic reactor be?

Posted: 05 Sep 2017 08:24 PM PDT

I'm interested in reality-grounded science-fiction power sources, and it was suggested to me that very small reactors could be make if we mastered aneutronic fusion. How small could an aneutronic fusion reactor be and remain safe for biological life to be around? How would the size affect the efficiency?

Note: I'm not an idiot, but I'm no engineer or nuclear physicist.

submitted by /u/VoidAgent
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Why is the center of the Milky Way galaxy always shown as a bright spot? Isn't there a supermassive black hole there?

Posted: 05 Sep 2017 02:52 PM PDT

How inaccurate are typically earthquake magnitude estimates?

Posted: 05 Sep 2017 10:16 AM PDT

Estimates of the magnitude of the earthquake created by the most recent North Korean nuclear test range from 5.6 to 6.4. That's a range of 0.8, corresponding to a factor 15 uncertainty in energy release. Is an uncertainty this big typical for an earthquake of this size?

submitted by /u/amaurea
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Why do swallowed hormones (e.g. The pill) work? Shouldn't the acid & proteases render them non-functional?

Posted: 05 Sep 2017 03:32 PM PDT

How were the electron transport chain and Krebs Cycle discovered?

Posted: 05 Sep 2017 05:04 PM PDT

Chemistry always boggles my mind.

submitted by /u/yosimba2000
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If quartz oscillates at an exact frequency, how can an atomic clock be any more accurate?

Posted: 05 Sep 2017 07:58 AM PDT

Other than supermassive black holes, what makes up our galactic core?

Posted: 05 Sep 2017 09:42 AM PDT

Most websites state that anything that agonises/antagonises receptors can only be removed by decay and be cleared naturally by the body. Is it feasible to unbind receptors without depending on half life?

Posted: 05 Sep 2017 04:39 PM PDT

Curious.

Suggestions:

Go inverse? (Assuming it was an Antagonist, treat it with an agonist and vise versa - going with a Antagonist with this example) I'd imagine that it wouldn't actually neutralize the antagonist that is causing the effect and instead you would with a constant fluctuation receptor activity? (I'd imagine) Also, you couldn't find exact agonist to negate the effect - finding a similar agonist sure, but you will end up with maybe more side effects where the agonists and antagonists don't match.

Clearing cycle? The brain has its own maintainence cells (Neuroglia) that do various things from providing homeostasis to removing cells and foreign substances. Pharmaceuticals that do antagonises/agonises receptors I would imagine wouldn't (?) detect as a threat because the pharmaceutical works. Does it? Is it not? Does it actually Are the special onset triggers for certain neuroglia? Would it even clear foreign receptor binders if specially triggered? etc. etc.

Food/Exercise? Something just as simple as eating the right water/fat soluble foods or doing loads of cardio or is it more complex than that?

To say a substance will cover everything is very ambiguous. Feel free (please) to use any other receptor examples or even solutions while explaining. I assumed serotonin receptors in my explanation.

Thank you.

Please, when you explain the answers please explain them in layman terms, I use all these terms when in fact I am just really dumb. Thanks a lot.

submitted by /u/Detourmenation
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Tuesday, September 5, 2017

I just looked at the sun with my eclipse glasses, and there are two black dots on the sun. What are those?

I just looked at the sun with my eclipse glasses, and there are two black dots on the sun. What are those?


I just looked at the sun with my eclipse glasses, and there are two black dots on the sun. What are those?

Posted: 04 Sep 2017 01:52 PM PDT

If you have your eclipse glasses, go look. Are they solar flares visible to the naked eye? Or are they planets?

submitted by /u/supaiderman
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Do animals know when a storm or hurricane is coming?

Posted: 04 Sep 2017 02:21 PM PDT

After going on vacation I was driving back to south Florida, about where the category 4 hurricane is supposed to hit and I realized that a whole lot of birds, a lot more than usual, we're moving north and since It's becoming colder everywhere I thought it should be the other way around where birds migrate south. Now with the hurricane looking like a very large threat, I figured that must be the reason for the birds fleeing.

Bonus question: if they can sense the hurricanes, why can't humans?

submitted by /u/jajsiehenso
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Why do hurricanes only hit eastern North America?

Posted: 04 Sep 2017 12:23 PM PDT

My question is mainly why eastern over western (California), but also I don't believe I've heard of hurricanes hitting anywhere else in the world either.

submitted by /u/SquanchyMelo
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What exactly is a laser composed of and what are the differences between different types of lasers?

Posted: 05 Sep 2017 02:29 AM PDT

I understand that lasers are light (focused?) and that's about it. Lasers fascinate me. You can buy a pointer at pretty much any corner shop and those are very fun to play with. What interests me more are those lasers that cause damage. The ones that cut through metal and can disintegrate fabric/paper. What is the difference between a basic laser pointer and a laser capable of cutting through six inches of metal like a knife through butter? Is it simply the intensity of the light? And if that's the case, through what means do we control the intensity? I apologise if this question seems overly basic but, generally speaking, I am not a man of science. Thank you in advance for your answers and I look forward to being educated further on the topic.

submitted by /u/ChosenNeravarrine
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What happens if a black hole is sucked in to another black hole?

Posted: 04 Sep 2017 11:19 PM PDT

What kind of impacts do nuclear tests have in general on nature?

Posted: 04 Sep 2017 01:52 PM PDT

What will happen to a piece of wood, placed in a "pot"with no oxygen and then placed over a fire?

Posted: 04 Sep 2017 03:18 PM PDT

also the same question but what if the "pot" was pressurised?

submitted by /u/Smoko854
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Why is there a Laser Gain Curve?

Posted: 04 Sep 2017 10:27 AM PDT

As we talk about a Laser and its active Medium, a figure like the one down below is often shown. I understood the basics of it but cannot think of a simple explanation why there is a gauss like gain curve above all passible frequency spikes.

I know one can say "the medium increases only those frequencies" but what principle is connected to this?

I also know that the curve does not always have to be gaussian but thats not the point of the question.

https://imgur.com/a/GwRNo

submitted by /u/Ic3Breaker
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Does the Pauli exclusion principle imply that there is a maximum possible density for any substance?

Posted: 04 Sep 2017 03:51 PM PDT

I.e. packed so tightly that it would be impossible to get any tighter without particles starting to occupy the same space? I know that under normal conditions, an atom is primarily made up of empty space between the nucleus and the electrons, so I'd imagine such a limit could only be reached in a black hole.

Are all black holes the same density? Or are black holes of a higher mass more dense? If some are more dense than others, do we have reason to believe that there is a limit to just how dense they can get?

submitted by /u/Lemonwizard
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What types of magnets are used in motors and generators?

Posted: 04 Sep 2017 08:54 PM PDT

For example, in wind turbines/electric cars. What are the advantages/disadvantages of different materials?

submitted by /u/JackA7X
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Do we have any idea what caused the Oh My God Particle to be moving so fast?

Posted: 04 Sep 2017 05:49 PM PDT

Chemistry: Molecule shape and electron geometries. Why isn't H2S linear?

Posted: 04 Sep 2017 02:02 PM PDT

I am a Chem 3 (organic chemistry) student so Im very familiar with chemistry. While studying I came across a simple question, "What is the molecular and electron geometries of H2S?" So I made the lewis diagram and realized that since Sulfur is in the same group as Oxygen and that I had drawn drawn a linear version of the water molecule. Then i thought, well what is different from Oxygen and Sulfer. Then i found that Sulfer actually has an electronegativity (e-neg) of 2.5 while oxygen has and e-neg of 3.5. after-which i realized that the difference between hydrogen and sulfur is 0.4 (marginally non-polar). And since linear is a non-polar structure i figured that "hey this must be why H2O is bent! it has a polar molecule from the difference in e-neg! this must be why the bent molecule forms!"-but I was wrong, the molecule is bent.

My question is why? No one else that ive seen has made a clear explanation as to why "the lone pairs push the bonding pairs away." in my mind, its just 4 electron pairs, and two of them just happen to have a proton attached to them. why does this molecule form a bent instead of a linear?!

If the answer is a theory or a scientific paper, please link it in your answers please!

submitted by /u/EpicPwn_343
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Has the discovery of a very large particular number ever refuted a widely believed conjecture in mathematics?

Posted: 04 Sep 2017 06:55 PM PDT

For example:

Goldbach's conjecture states that every even integer greater than two is the sum of two primes. Computer calculations have verified that this holds true for integers less than 4 x 1018 , but nevertheless a full proof has never been discovered.

Now, if we were to discover a single even integer greater than 4 x 1018 Goldbach's conjecture would be false. In the history of mathematics has something like this ever happened? Has a widely believed conjecture been rendered false due solely to the discovery a single large number that refutes it?

submitted by /u/only_bad_days
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Why Tsar Bomba - the most powerful bomb ever detonated - could have destroyed the Earth according to its creators?

Posted: 04 Sep 2017 11:27 AM PDT

According to the Russian physicists who created the bomb, the explosion could have started a self-sustaining nuclear reaction in the ocean, leading to the planet's destruction. How is that possible?

submitted by /u/EchoOne11
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How can we tell what path a hurricane will take days in advanced? How come we can't determine high probability paths for the hurricane further in advance?

Posted: 04 Sep 2017 02:05 PM PDT

I'm a dumb kid.

submitted by /u/The_Thrill17
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In a flood situation, what walls are holding up the water?

Posted: 04 Sep 2017 06:56 PM PDT

Are gas giants (up to 12 Jupiter masses) more likely around hot stars (O-A class) or cold stars (K, M, Brown Dwarf)?

Posted: 04 Sep 2017 10:03 AM PDT

I can't find reliable data on planetary likelihood per stellar class.

submitted by /u/MrJadexxxxxxx
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Why does clipping a sine wave create a square wave?

Posted: 04 Sep 2017 12:57 PM PDT

I understand why an infinite series of odd harmonics at proportional amplitudes and frequencies creates a square wave, and I understand the additive properties of waves.

I also understand why overdriving a sine wave through an amplifier/circuit cuts off the top and bottom of the wave, giving it a "square" appearance.

I guess I don't understand the reasoning the other way around. How and why does the fairly simple operation of clipping turn one sine wave into an infinite series of sine waves?

It may seem like I'm asking a question I've already answered, but that's not my intention, or maybe I'm not getting something.

Let's say you didn't offhand know the harmonics of a square wave. How could you derive them from the shape of a square wave?

Odd harmonics generate square/triangle waves. Why do square/triangle waves generate odd harmonics?

Does that make sense, or is the answer just, "dumb dumb, what about the transitive property don't you understand?"

submitted by /u/diamondbackmanhunter
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Monday, September 4, 2017

Is a single Elephant's skin cell bigger than a human's skin cell?

Is a single Elephant's skin cell bigger than a human's skin cell?


Is a single Elephant's skin cell bigger than a human's skin cell?

Posted: 03 Sep 2017 01:15 PM PDT

People built a "Z machine" on Earth that creates a temperature of 2 Billion Kelvin. How can this temperature be generated and why does this temperature not melt the entire facility that creates it?

Posted: 04 Sep 2017 02:37 AM PDT

For scale, this is approximately 100x hotter than the center of the sun.

Given that the sun only has an outside temperature of 5,500K and easily heats up Earth to 300K+ over a distance of 150 million kilometers, shouldn't a temperature of 2,000,000,000K on Earth itself cause severe damage of some kind?

submitted by /u/Linnun
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How soon after an organism 'dies' are all of its cells dead? its bacteria?

Posted: 03 Sep 2017 10:12 PM PDT

Let's say an organism dies instantaneously (no previous oxygen deprivation). How long would the cells continue to be alive despite the macro organism being considered dead? How long would the bacteria within and on the body last? How much of a time difference would it be, if any, between say an ant and a blue whale?

submitted by /u/zincinzincout
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What are the repercussions of detonating a nuclear bomb underground?

Posted: 03 Sep 2017 10:56 PM PDT

When the immune system damages the gut of a coeliac person who eats gluten, does the mechanism of action differ significantly from that of an allergy (igE+histamine+basophils)?

Posted: 04 Sep 2017 05:18 AM PDT

Coeliac's is often described as an "allergy", but people who've been educated in the field say it's "technically not an allergy and technically not autoimmune, though very similar to both". I'd like to better understand what this means.

Bonus question: Do allergies have something similar to "levels" like coeliac's? Or is it more like you're either allergic or non-allergic?

submitted by /u/katinla
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How does one measure the thickness of gold foil?

Posted: 04 Sep 2017 06:03 AM PDT

What, other than the tides, is noticeably affected by the moon's gravity?

Posted: 03 Sep 2017 01:46 PM PDT

Why does the deficiency of some vitamins like b12 can cause depression?

Posted: 03 Sep 2017 07:48 AM PDT

Cats can shake their head at a surprisingly rapid rate. How do they avoid whiplash and concussions while doing this?

Posted: 03 Sep 2017 04:20 PM PDT

What is the mechanism by which nuclear reactors produce energy?

Posted: 03 Sep 2017 09:24 PM PDT

To be more specific, I'm interested in what happens with the nuclear fuel and how the energetic reaction is sustained. I know that it uses fission (commonly U-235) to release the energy, as well as the basic idea of neutron moderation, and I'm aware of but not fully versed on the idea of fast and slow neutrons.

My questions include: * Is the reaction a self-sustaining chain reaction? That is, could it be considered at the precipice of criticality? * Followup, if It is NOT, then how is the reaction maintained? How do they provide enough neutrons for a sustained and fairly constant energy production? * How exactly are the decay products handled? How quickly do they accumulate? And what do they do to the energy output? (Also, if possible, the common and notable decay products would be awesome!) * How does "neutron moderation" occur, and what is the point of it? My picture of the reaction is of solid fissile fuel (i.e. like those diagrams you see explanation fission). Where does the moderator interact with the fuel?

I hope these questions make sense! My understanding of physics is analogous to that of a hobbyist astronomer, so explaining it at that level is ideal. However, I'm fairly content with getting into more mathematical sides of things if necessary. That said, these questions are more of the engineering side (which is the category where I'm placing it), so I'm hoping it will have more conceptual answers.

submitted by /u/Aethi
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How exactly can elements be changed into other elements by radiation?

Posted: 03 Sep 2017 03:17 PM PDT

If I remember correctly, the radiation of electrons can disturb and add/take away electrons from another element to change the element itself. If I were to do this to a big block of gold, could I possibly change this into a block of silver or even into a gas like oxygen?

submitted by /u/Bradleyharris88
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Could a neutron detector be used to verify underground nuclear tests?

Posted: 03 Sep 2017 11:53 AM PDT

If the symptoms of an illness are typically the body creating a hostile environment to get rid of the infection (runny nose, fever, etc.), what do viruses/bacteria actually do?

Posted: 03 Sep 2017 08:29 AM PDT

Or, what would an illness look like if our immune system didn't do all of those things to destroy the viruses/bacteria?

submitted by /u/mozrik
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How much of the fissionable materials (Uranium, Thorium) are in the Earth's core and how often does it combine into critical mass to explode?

Posted: 03 Sep 2017 10:25 AM PDT

How can waxing and waining gibbous phases of the moon look like they do?

Posted: 03 Sep 2017 03:22 PM PDT

The shadow the earth throws on the moon in those phases looks like the earth is a crescent instead of a sphere. I can't wrap my head around it. Can someone please explain.

pic of lunar phases

submitted by /u/I_want_fun
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Do trees effect the wind speed/potential wind damage of a hurricane?

Posted: 03 Sep 2017 03:35 PM PDT

With Hurricane Irma looming, I was wondering if living in a rural area with dense tree and brush coverage has any effect on the wind speed of the storm at ground level, and by extension could that reduced wind speed lessen the potential damage caused by the wind to homes in that area? Edit: of course, trees can fall and branches become projectiles, I'm more curious about wind damage only from a powerful major hurricane.

submitted by /u/DobbyDooDoo
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What is it exactly that energy boosting substances like caffeine and ginseng do to our body in order to provide an alert/energized state?

Posted: 03 Sep 2017 09:05 AM PDT

How is queen bee becoming a queen bee ? Is it natural or is it acquired ?

Posted: 03 Sep 2017 02:08 PM PDT

From the Light Side of the Moon, are there phases of the Earth?

Posted: 03 Sep 2017 06:28 PM PDT

What happens to the inside of planets as they age?

Posted: 03 Sep 2017 07:03 AM PDT

I was thinking about the Earth's core today and how they should, due to entropy, cool over time. However it will still be under enormous pressure. What happens to different planet's cores over time? Do they completely solidify? Similarly what will happen to gas giants as they age?

submitted by /u/SailingOnFishlessSea
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With regards to the Diving Reflex, can we hold our breath longer while underwater than we can on land?

Posted: 03 Sep 2017 07:48 AM PDT

Does Hurricane Harvey affect the weather for the rest of the United States? If so, how, and how far?

Posted: 03 Sep 2017 07:56 AM PDT