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Friday, December 27, 2019

If helium keeps floating up and up, how do we still have helium left on Earth after more than a billion years? Also, helium is a gas. Where do you actually go to find helium on Earth?

If helium keeps floating up and up, how do we still have helium left on Earth after more than a billion years? Also, helium is a gas. Where do you actually go to find helium on Earth?

If helium keeps floating up and up, how do we still have helium left on Earth after more than a billion years? Also, helium is a gas. Where do you actually go to find helium on Earth?

Posted: 26 Dec 2019 12:28 PM PST

We always hear the phrase "97% of scientists back climate change" So what is the argument against it from the 3%?

Posted: 26 Dec 2019 05:17 PM PST

Can global warming cause more earthquakes?

Posted: 26 Dec 2019 11:08 PM PST

Saw in a thread that a rise in sea level will increase the number of tsunamis. But will the earth warming up increase all tectonic activity, or will there just be more tsunamis because there is more ocean?

submitted by /u/Givemeahippo
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Would a denser atmosphere increase the power of a nuclear explosion by any significant amount?

Posted: 26 Dec 2019 08:10 AM PST

How does a Shkadov Thruster produce a net thrust toward the mirror?

Posted: 26 Dec 2019 02:25 PM PST

I was watching the latest Kurzgesagt video about stellar engines but after they present that a net thrust of a Shkadov Thurster is produced toward the direction of the center of the mirror (link to video at relevant timestamp, they don't actually explain why that thrust happens, and I can't figure it out.

It seems to me that the outward emission of the Sun's 1045 photons / sec would be pretty much uniformly distributed in all outward directions, each with it's own tiny momentum that conversely "pushes" inward against the Sun as it leaves, but after emission, why would those photons' interaction with any object somehow impart a thrust to the Sun? Do they collectively push the mirror away and the gravitational attraction of the mirror pulls the sun along with it? If so, what is the difference in mass between the micron-thin mirror and the entire Sun itself? It seems the delta would be so incredibly lopsided toward the Sun that it really wouldn't matter, but that is why I'm here.

Thank you!

submitted by /u/Stoke-me-a-clipper
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How does a lava lamp work?

Posted: 26 Dec 2019 07:29 PM PST

Seriously though how does a lava lamp work?

submitted by /u/sombrerolord69
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Shouldn't the forces on each side of the z line in sarcomeres cancel out?

Posted: 26 Dec 2019 03:08 PM PST

If measles infection diminishes existing and future immune response, what are implications for other vaccinations in such individuals? [Medicine]

Posted: 26 Dec 2019 11:12 AM PST

for example:

How measles causes the body to 'forget' past infection Science 01 Nov 2019: Vol. 366, Issue 6465, pp. 560-561 DOI: 10.1126/science.366.6465.560

The diminished antibody shield means that after a case of measles, unvaccinated children become vulnerable again to viruses they had been exposed to in the past.

So if this is the case (interpretation is beyond my capabilities; I do see there is contention but I can't make heads or tails of it) do the described effects occur only with naturally occurring immunity, or also immunity conferred by vaccination? If someone has a documented history of other vaccines, would they benefit from redoing their primary series post-measles? Does the long term suppression of new acquisition of immunity imply a modified schedule in future vaccines such as is the case for sickle cell disease (not, to avoid a common confusion, sickle cell trait)?

Of course the above work was conducted in a group who are presumably never-vaccinators for all formulations. But in the global context, vaccine availability is inconsistent. So infection with an ostensibly preventable disease is not an indication of attitude towards vaccines generally.

Also: Incomplete genetic reconstitution of B cell pools contributes to prolonged immunosuppression after measles. Sci Immunol. 2019 Nov 1;4(41). pii: eaay6125. doi: 10.1126/sciimmunol.aay6125.

submitted by /u/Diluent
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How close are chickens related to dinosaurs?

Posted: 26 Dec 2019 10:50 AM PST

Could we call them dinosaurs or is the difference too big?

submitted by /u/RandomInternetGuy014
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How exactly did we map the human genome?

Posted: 25 Dec 2019 08:25 PM PST

So scientists have already mapped the human genome for some time now, but I'm wondering, how did scientists come to a consensus that this is the genome of an average human? I assume they got a DNA sample from someone, and then used it to map the genome of our species. What I don't understand, is that if we used some random person's DNA, then it wouldn't be our genome, it would be that person's, complete with any abnormalities they have in their DNA. So how do we know the genome represents all of humanity? Sorry if this seems stupid.

submitted by /u/TheDominantSpecies
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What controls involuntary reflexes like heartbeat?

Posted: 25 Dec 2019 03:53 PM PST

Do carnivorous mammals and birds clean themselves after eating? If so, how?

Posted: 25 Dec 2019 06:01 PM PST

I've read here that Komodo dragons will lick their lips for 15-20 minutes after eating as well as rub their heads inside leaves to clean themselves so I was wondering if and how mammalian and avian carnivores do this. It would sorta make sense to do (based on my limited knowledge) to prevent infections but It seems pretty inconvenient and hard to clean with fur and feathers that blood could stick to and dry on.

submitted by /u/Random_Username9105
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Why do other diseases not cause AIDS?

Posted: 26 Dec 2019 01:02 AM PST

I know other diseases cause types various types of immune problems, but why are none classified as AIDS? The name would imply it was any immune deficiency caused after birth.

submitted by /u/AtmosScriptor
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Thursday, December 26, 2019

Is a neutron star a perfect electrical insulator?

Is a neutron star a perfect electrical insulator?

Is a neutron star a perfect electrical insulator?

Posted: 26 Dec 2019 03:43 AM PST

Neutron stars don't contain any electrons, right? Does that mean that they have precisely zero electrical conductivity? Or is it more complicated than that?

submitted by /u/iwanttobepart
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What noise reduction and smoothing algorithms are good for filtering thermistor-based temperature data?

Posted: 26 Dec 2019 02:27 AM PST

Hello folks,

Title says it all, but to clarify I am looking for a good algorithm to reduce noise and smooth out data coming from a thermistor sensor that is monitoring the temperature of a hot-water pipe. Data points are separated in time by 5 minutes to one hour. I would prefer an algorithm that does not cap min/max values. Complexity or memory / CPU consumption is not an issue. The algorithm does not need to be predictive, as all the necessary data is already there.

Cheers, Mike

submitted by /u/h4tt3n
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What is the speed of electricity?

Posted: 25 Dec 2019 08:01 AM PST

We know the speed of sound. We know the speed of light. Do we know the speed of electricity? It appears instant, but it can't be the speed flight because electrons have mass and therefore can't reach that speed. (right?)

I know many factors go into current and voltage and all that, so let's just assume basic, household electricity: 120 volts, 14 gauge solid copper wire, distance of 20 feet (switch to ceiling light).

How fast does the electricity move from the switch to the light?

submitted by /u/pnkstr
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Why is antivenom fast acting, while vaccines take a couple weeks to provide immunity?

Posted: 25 Dec 2019 06:23 PM PST

From what I understand, it seems like antivenom and vaccines are made through the same process (injecting an animal with the pathogen and isolating the antibodies). So why is antivenom used as a "fast fix" to snake bites, while getting a vaccine when you've already caught the virus isn't really effective, and you normally have to wait like two weeks to see immunity?

Edit: along the same lines, why doesn't exposure to antivenom lead to immunity to venom?

submitted by /u/myhightide
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At the supermarket bulk coffee selection, they have coffees from different regions of the world. Are those regions growing different species of coffee? In other words, is what makes coffee distinctive WHAT is grown, or HOW it grew (soil and temperature wise)?

Posted: 25 Dec 2019 09:48 PM PST

Given that famotidine does not decrease gastric emptying rate, why does it decrease the effectiveness of lactase supplements?

Posted: 25 Dec 2019 03:38 PM PST

People who are lactose intolerant often use lactase pills when having dairy (taken a few minutes before the dairy) to manage the intolerance. However, it has been reported that (for those who also have GERD), if they take a Pepcid (famotidine) prior to a dairy meal - even though they use lactase pills, they end up suffering as if they never took any lactase at all.

Originally, I thought this was because the Pepcid was slowing down the digestion, so the lactase wasn't hanging around long enough to be effective. However, doing some research led me to discover that Pepcid doesn't delay the gastric emptying rate (1).

That being the case, can someone with a better knowledge of biology explain to me why Pepcid causes this effect?

 

References:

  1. Scarpignato, C., Tramacere, R., & Zappia, L. (1987). Antisecretory and antiulcer effect of the H2-receptor antagonist famotidine in the rat: comparison with ranitidine. British journal of pharmacology, 92(1), 153–159. doi:10.1111/j.1476-5381.1987.tb11307.x
submitted by /u/TA44861
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What are Wigner Functions used for in Quantum Optics?

Posted: 25 Dec 2019 05:46 PM PST

I've recently been studying Wigner Functions for my Master's degree and most of the examples I find are in Quantum Optics. I don't know much about Quantum Optics nor I have the time to study it now, but Wigner Functions are hella fun and I'd like to know more about them

submitted by /u/UndercoverDoll49
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Why oyster shells are "irregular"?

Posted: 25 Dec 2019 09:17 AM PST

My new favourite pastime is watching coastal foraging videos on youtube and I noticed that oysters look very different from other clams. Oyster shells are very irregular, uneven and bumpy. Why is this a thing? What are the benefits of having a "weird" shell? And most importantly, what is the cause? A random mutation caused a malfunction on "shell making gene" and oysters went "eh, this is my life now" or is there a sensible explanation?

submitted by /u/stalinorgel
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[Astronomy] What is happening with Betelgeuse – and how "unique" is what we are currently observing?

Posted: 24 Dec 2019 11:03 PM PST

Apparently Betelgeuse is about to go supernova – or at least if you believe what non-science media has to say about it. The star has dimmed by a factor of two in the span of two months, and that's all the general public knows (though we don't even know what "dimmed by a factor of two" does indeed mean). What we don't know is whether that's even newsworthy.

So my general question is – just what is happening to Betelgeuse?

• How significant is the dimming? What does "dimmed by a factor of two" mean in the context of Betelgeuse? Can you put that into perspective?

• From the perspective of its giant size, how significant is the speed — the star went so dim so quickly, effectively under two months?

• We don't have historical data that goes beyond 300 years back. How likely is the possibility Betelgeuse has been dimmer in the past?

• Is this process observable with naked eye by the general public?

And, most importantly:

• Apart from "about to go Supernova", what might be some processes that can explain the change?

submitted by /u/AvalancheMaster
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If I drink a pint of water, how much of it is absorbed into my body becoming part of my organs and blood versus being excreted as urine or sweat?

Posted: 24 Dec 2019 10:39 PM PST

Does a twin have increased chance of having twins?

Posted: 24 Dec 2019 08:40 PM PST

Im a guy and twins run quite heavy in my family both my dad and his brother have twins and I've been told triplets are in my family as well. So my question is do I have an increased chance of having twins or triplets. I know it might sound stupid to some of you but it said worry of mine any help is appreciated.

submitted by /u/dragonator7000
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If the fastest that neurons can oscillate at is a few hundred Hz, then how can we hear and process sound frequencies up to ~20,000Hz?

Posted: 24 Dec 2019 04:57 PM PST

I know about the cold shock response but is it possible to have a warm shock response if the body is suddenly submerged in very warm water?

Posted: 24 Dec 2019 02:23 PM PST

Why does the flame of a candle not spread from the wick to the molten wax around it?

Posted: 24 Dec 2019 06:00 PM PST

How do eradicated/mostly eradicated viruses come back?

Posted: 24 Dec 2019 07:17 PM PST

Spurred by the news of the first confirmed case of Measles in the Austin Texas area in 20 years. I believe most viruses can't live outside a host for extended periods of time. How does something that hasn't infected a person in that region for 20 years suddenly show up? Where do the first viral cells come from to infect someone?

submitted by /u/ParzivalD
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Wednesday, December 25, 2019

If you were in a completely dark room, and you somehow could see in the dark. Would you be able to see your reflection in a mirror?

If you were in a completely dark room, and you somehow could see in the dark. Would you be able to see your reflection in a mirror?

If you were in a completely dark room, and you somehow could see in the dark. Would you be able to see your reflection in a mirror?

Posted: 25 Dec 2019 05:13 AM PST

I know this sounds dumb, but this was just a shower thought i got.

submitted by /u/AngusMcFifeXV
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How fast would the earth have to spin in order for things to fly off into space?

Posted: 24 Dec 2019 05:44 AM PST

Does convection operate independent of scale?

Posted: 24 Dec 2019 11:34 AM PST

For example, is there convection within the cytoplasm of cells? Does it work the same way on the scale of oceans? At what point do the intermolecular forced and actual size of molecules cause the system to break down?

submitted by /u/boxcoxnc
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If you had a gas impermeable tube from the earth's surface to space (beyond the atmosphere) would it create a perpetual vacuum tube?

Posted: 25 Dec 2019 06:46 AM PST

Ok so my Dad and I are discussing this over Christmas breakfast. The idea is this: a gas impermeable tube from the surface to "space" aka far enough away from the surface that there is a large density gradient between both ends. My thought is that there is a nearly infinite density gradient between both ends and therefore air will flow from the surface towards space until the gradient reaches equilibrium (aka when there's the same amount of air on the surface as there is at the exit point. My Dad thinks that there will be some sort of equilibrium that occurs similar to the stratification of the atmosphere within the tube and therefore the flow will stop far before we deplete a significant portion of atmosphere. Any one have a decisive answer?

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

Posted: 25 Dec 2019 07:08 AM PST

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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How come Methuselah star is older than the universe?

Posted: 25 Dec 2019 06:05 AM PST

This star is calculated to be 200,000,000 years older than the universe.Has people did research with this star carefully.The age of the universe was accurately measured.So how come Methuselah is older than the universe.

submitted by /u/Fanboy375
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Why in non-newtonian fluids, viscosity (which is a propriety of the fluid) depends on velocity ?

Posted: 24 Dec 2019 09:23 AM PST

I see this type of fluids being not intuitive (welcome to science!) and I can't get my head around this fact, since viscosity is a propriety of a fluid (which depends on temperature,..).

Why does this happen to certain fluids ? Why should some fluids viscosity depend on velocity and others do not ?

submitted by /u/Tuareg99
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What does transcription factors have to do with T cell exhaustion?

Posted: 24 Dec 2019 12:29 PM PST
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Tuesday, December 24, 2019

What is the smallest known object that still occupies space?

What is the smallest known object that still occupies space?

What is the smallest known object that still occupies space?

Posted: 23 Dec 2019 07:00 PM PST

So my understanding is that, according to the standard model, the fundamental particles are all point particles that occupy no space (or atleast, it is meaningless to talk about them having a size).

But if I wanted to identify a "physical object" (I know that gets a bit fuzzy at these scales) that occupies some physical space, it must be some form of hadron, no? From looking online, it appears protons have a diameter of roughly 1e-15m, but is there anything smaller than that? I thought at first mesons might be, as they are composed of only two fundamental particles, but Wikipedia says that they are actually larger than protons. That leads me to believe that maybe more quarks lead to smaller objects, but that now gets in a territory that I know absolutely nothing about.

So, is there a widely accepted "smallest" thing? Something that still has an accepted or measured (or even predicted size) that isn't a concept like the Planck length.

submitted by /u/ChrisGnam
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Why do massages and stretching feel so good? What is happening on a physiological and biological level?

Posted: 23 Dec 2019 04:40 AM PST

I know this question sounds silly but I just got a massage today and I was wondering why they are so beneficial to our body. Do they increase blood flow or reduce lactic acid buildup? Does the action produce endorphins and dopamine in our brain? Why do our muscles get sore anyway?

submitted by /u/anixetea73
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Do the hearts of animals with multiple hearts synchronize at the time or a particular pattern ?

Posted: 22 Dec 2019 08:01 PM PST

What’s the temperature inside a cavitation bubble?

Posted: 22 Dec 2019 08:47 PM PST

What is the temperature inside a water cavitation bubble? My employer gave me a pump operator class where I remember it saying it was hotter than the surface of the sun. I'm now in a heated debate with a coworker who insists otherwise. Neither of us can find a solid answer on the web. Please help.

submitted by /u/earthtoedward
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What stops your lungs from inhaling water from a humid environment like a sauna or a shower?

Posted: 22 Dec 2019 05:22 PM PST

What are signs of damage to the medulla?

Posted: 22 Dec 2019 03:53 PM PST

And can you have damage to the medulla without knowing it?

submitted by /u/funnel_out
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What is emf and voltage and what's the difference between both of them?

Posted: 22 Dec 2019 03:29 PM PST

Why are so many dinosaur fossils from laramidia and not appalachia?

Posted: 22 Dec 2019 05:58 PM PST

And why are so many of laramidia fossils from the eastern coast of the continent?

submitted by /u/iLoveClassicRock
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How far up will helium travel?

Posted: 22 Dec 2019 04:07 PM PST

Will helium continue up and disappear into space or will it stay somewhere in the atmosphere? If it stays in the atmosphere, how far up?

submitted by /u/nicfris
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Do rutting mammals, or dinosaurs such as pachycephalosaurus, suffer from brain damage the way football players do? Such as chronic traumatic encephalopathy?

Posted: 22 Dec 2019 01:59 PM PST

Why does caramelising sugar make it bitter rather than more sweet?

Posted: 22 Dec 2019 02:04 PM PST

Is the human body "better off" fighting non-life threatening infections, which the body is able to eventually overcome on its own, using its own immune response or is it better off receiving external aid, like antibiotics?

Posted: 22 Dec 2019 01:35 PM PST

That is, from a perspective of longevity and the "best course of action" for the body's immune system, when ailing from a non-life threatening infection - say, the common cold or a viral infection that manifests as a fever, which the body is able to eventually "defeat" on its own - is the human body better off tackling it using its own immune response or is it better off receiving external aid (like antibiotics)?

If the body is left to tackling the infection using its own immune response, and the temporary bodily discomfort notwithstanding, is an otherwise healthy immune system able to fully recover from the damage caused by such an infection? Further, if it is able to recover, is such recovery to status quo, or does the immune system recover to be "stronger"?

P.S. Please excuse the verbosity.

submitted by /u/_Veni
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Could other animals develop Tinnitus or is it something "special" to us?

Posted: 22 Dec 2019 01:32 PM PST

And if they cannot develop it why would that be?

submitted by /u/Brookies1976
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The SIRT6 protein has been identified as very important for multiple health reasons - but how is it made or how can one stimulate its production through diet? Can it be ingested?

Posted: 22 Dec 2019 04:15 PM PST
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Monday, December 23, 2019

How are mountains formed in non-tectonic planets?

How are mountains formed in non-tectonic planets?

How are mountains formed in non-tectonic planets?

Posted: 22 Dec 2019 04:14 PM PST

What causes the global cooling after a Milanković cycle?

Posted: 23 Dec 2019 03:47 AM PST

Hey,

I'm reading about the climate change, and one prominent argument is the connection between global CO² concentration and temperature. Afaik the temperature increases periodically because of Milanković cycles, which causes the CO² levels to rise, which in tern increases the temperature further.

The question I can't seem to find an answer to is this: If the Milanković cycle only kicked of the feedback-loop between temperature and CO² and both are at very high levels, what causes them to decrease again after a certain amount of time?

Thanks!

submitted by /u/niggo372
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Why are Ice and Diamond slippery but Glass and dry ice not?

Posted: 23 Dec 2019 03:43 AM PST

I understand that ice has a surface layer that's much more mobile (though not really liquid water) which makes it very slippery. This, so I am told, is due to it being a polar covalent molecular solid. Fair enough.

What I don't understand then is why Diamond is even more slippery, when it is a monatomic non-molecular, non-covalent crystalline solid.

It can't be simply smoothness. Optical quality glass isn't remotely slippery, yet rough, sharp, opaque ice created from freezing rain is still slippery even against other ice. Why is rough ice slippery, diamond slippery, but glass not?

And how about dry ice? It's not nearly as slippery as water ice as long as the thing touching it is also cold.

What about metals? Aluminium (with the oxide layer) isn't slippery. Nor is gold, steel, copper, Zinc, Lead, Alkali metals, etc.

So what makes ice and diamond slippery and other smooth, solid surfaces not? Is there some kind of rule for what materials will be slippery?

submitted by /u/pds314
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At wich point a sound wave becomes classified as a shock wave?

Posted: 22 Dec 2019 08:38 AM PST

Did life on Earth originate from a single location?

Posted: 22 Dec 2019 09:47 AM PST

Since all galaxies are moving can we theoretically map and trace back their paths to find a common point of origin (i.e. big bangs’ “ground zero”)?

Posted: 22 Dec 2019 04:48 AM PST

Why are the rings of Saturn streaked?

Posted: 22 Dec 2019 07:21 AM PST

The rings are made from rocks and gasses, so I would think it would look like a cloud of brown rocks flying around, are the gasses colored? How is it so flat?

submitted by /u/superbrian111
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Is intelligence inherited or environmental?

Posted: 21 Dec 2019 11:08 PM PST

What causes flesh to rot?

Posted: 22 Dec 2019 07:52 AM PST

Is the cause internal, external, a chemical reaction?

submitted by /u/de420swegster
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Do the parasympathetic and sympathetic nervous systems utilize different nerves? Are they made of distinct structures?

Posted: 21 Dec 2019 08:59 PM PST

Which plant have the highest oxygen production to size ratio ?

Posted: 21 Dec 2019 03:03 PM PST

How does recharging a battery work?

Posted: 21 Dec 2019 11:05 PM PST

Since matter cannot be destroyed where do the spent atoms go. I may have a misunderstanding of how chemical bonds are used but I don't really understand the concept of how recharging something that is based off of chemical reactions. Can you simply redo the reactions that produced the energy by adding more electrons?

submitted by /u/FuriousFighter13
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