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Friday, April 26, 2019

How does iron ore form from individual molecules created in a generation 1 star?

How does iron ore form from individual molecules created in a generation 1 star?

How does iron ore form from individual molecules created in a generation 1 star?

Posted: 25 Apr 2019 03:59 PM PDT

1st generation stars create heavier elements in form of atoms and then explode sending these elements off into space when syar dies and goes nova.

How do these stray atoms group together into tangible iron nuggets or iron ore? Is that happening while drifting in space or does some geological mechanism cause the stray atoms to group into a vein of tangible iron ore? Thanks.

submitted by /u/WatchHores
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Why do we measure decay in half-lives rather than just lives?

Posted: 25 Apr 2019 07:50 PM PDT

Why is the newborn heel prick test is done on the heel?

Posted: 25 Apr 2019 02:21 PM PDT

Wondering why the heel spesifically.

submitted by /u/unrealdreams
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Would LIGO results improve if there were a third branch perpendicular to the existing two?

Posted: 25 Apr 2019 11:32 AM PDT

Is an algorithm that’s good at identifying one type of objects in pictures/videos (e.g. faces, cars, birds) expected to be a better starting point for learning to identify other types of objects, or is it just as easy to start from scratch?

Posted: 26 Apr 2019 02:43 AM PDT

[Physics] [Chemistry] Why does something smoulder instead of be on fire with a flame? What's happening physically?

Posted: 25 Apr 2019 08:27 AM PDT

How are meteors/asteroids tracked?

Posted: 25 Apr 2019 09:10 AM PDT

After watching news reports covering the Chelyabinsk meteor of 2013, it seems that this particular meteor was unable to be tracked because of it's small size (about 2 SUV's).

submitted by /u/NuREVa
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Is there any support for fields that exist that have no observed particles that they interact with?

Posted: 25 Apr 2019 09:01 PM PDT

Every fundamental particle appears to be excitations of their own respective field which pervades all space and time, but does it appear that there could be fields which just never get excited, but also overlap the others waiting for an interaction that doesn't exist?

submitted by /u/pimpmastahanhduece
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Are all IIEE float and double numbers rational?

Posted: 25 Apr 2019 02:22 PM PDT

Throughout the history of the Earth, which land areas have shifted the least and the most?

Posted: 25 Apr 2019 03:30 PM PDT

We (hopefully) all know that Earth used to be a single continental landmass that has since separated and drifted apart immensely. What land masses have shifted the least over these few hundreds of millions of years. And what are the implications (climate-wise, biological, cultural, etc) of experiencing a large shift versus a small shift?

submitted by /u/hardysrule1997
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How can an Earthquake alter the Earths rotational speed?

Posted: 25 Apr 2019 06:55 PM PDT

Just saw an article which said that an earthquake in Japan in 2011 caused the Earths rotation to speed up shortening our days by 1.8 milliseconds.

How would this work? Earth is free floating in space so I would think for it's rotation to be altered an external force would need to be applied to the entire earth no? Like an asteroid impact or something?

submitted by /u/TTTyrant
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Size comparison: Simbakubwa Kutokaafrika vs Andrewsarchus Mongoliensis?

Posted: 25 Apr 2019 05:47 AM PDT

Recent news articles declare Simbakubwa to be the largest carnivorous land mammal of all time, beating out the polar bear. I was under the impression that this title was held by Andrewsarchus, but I can't find any sources comparing the size of each. Given that we only have limited fossil remains of these 2 enormous predators, which was likely the larger beast?

submitted by /u/Supervinyl
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Are sand grains permanently the size that they are? If so, why don’t they erode any smaller?

Posted: 25 Apr 2019 08:33 AM PDT

What is dandruff and how does it form?

Posted: 25 Apr 2019 05:05 AM PDT

How did improperly treated water cause lead to be released into Flint, Michigan’s water system?

Posted: 25 Apr 2019 05:19 AM PDT

What makes cow's milk amenable to homogenization that is different from plant milks that use emulsifying agents?

Posted: 25 Apr 2019 05:35 AM PDT

Are all batteries subject to degradation over time?

Posted: 25 Apr 2019 02:55 AM PDT

Despite the recent shifts from fossil fuels to batteries, it seems that lithium-ion will always be subject to irreversible chemical degradation, reducing capacity by up to 50% given enough time.

Is this the case with all batteries e.g. lead acid? I read something about graphene batteries not having this problem.

submitted by /u/Nilsdog
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If hemoglobin is more efficient than myoglobin, why do we have both?

Posted: 24 Apr 2019 08:25 PM PDT

Is there a maximum distance between the mean and median of a set of data, say as a function of the standard deviation?

Posted: 24 Apr 2019 09:12 PM PDT

For example, is it possible to have a set of data with mean mu=0, median med=100, and standard deviation sigma=1. The standard deviation is "small", so the data should be "close together", which doesn't seam compatible with having enough data points sufficiently smaller than 100 to force the mean to be 0.

Edit: This may be bad form, but I think I answered my own question. I can prove
|med-mu|is at most 2sigma for any set of data. This is a crude estimate, and a better inequality might exist. I can post the proof later, if there is interest.

submitted by /u/i_want_to_go_to_bed
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Monospecies activity of pollinators other than bees?

Posted: 24 Apr 2019 08:33 PM PDT

Long ago (VERY long ago) I was told that bees leave the hive and visit only one flower species on that trip. This is confirmed by noting the type of pollen gathered upon returning.

Today, I'm watching Nature on butterflies however, and wing pollination was mentioned. Since this is not a food source, there is less, if any, reason to only visit one species per day.

My question is: Are butterflies bound by the monospecies rules of bees? I understand that a single flower type may all be most ripe and providing the most nectar today, but if there are multiple good nectar sources, will butterflies visit all of them and perform pollination for multiple species on the same day?

submitted by /u/diogenes_shadow
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Thursday, April 25, 2019

How do we know it rains diamonds on saturn?

How do we know it rains diamonds on saturn?

How do we know it rains diamonds on saturn?

Posted: 24 Apr 2019 04:04 PM PDT

AskScience AMA Series: You've most certainly heard stories about young athletes collapsing and dying while playing their beloved sport. These athletes often have the rare, genetic heart condition ARVC. I am Dr. Cynthia James, and I study how to better help people who have this disease. AMA!

Posted: 25 Apr 2019 04:00 AM PDT

Hi Reddit! As a researcher and genetic counselor at Johns Hopkins Medicine, I'm part of a team that recently helped create a computer program that predicts who is at risk of sudden death in people with arrhythmogenic right ventricular cardiomyopathy (ARVC). This tool will help us figure out who would benefit most from an implanted device that shocks the heart to get it back into rhythm. And, it could prevent 20 percent of patients with the disease from receiving unnecessary - and potentially risky - surgery to place a device that is not needed.

Often, people don't find out that they have ARVC until they experience a near fatal or fatal cardiac event. You may even have a family member who suddenly died because of this, which means someone else in your family - maybe even you - could have it. I'll see everyone at noon Eastern (16 UT), ask me anything!

submitted by /u/AskScienceModerator
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If a proton is one down and two up quarks, and a neutron is two down and one up quarks, then how does combining a proton with an electron (a lepton) make a neutron? Is the lepton somehow turned into a down quark?

Posted: 25 Apr 2019 04:14 AM PDT

In Ul ar Collateral Ligament Reconstruction (Tommy John surgery), is the donor tendon anastomosed end to end, or is it overlapped? Also, why is a donor tendon better than some synthetic elastic band?

Posted: 25 Apr 2019 06:14 AM PDT

The ten black hole merger events detected by LIGO over the past five years seems like a lot. Is it?

Posted: 24 Apr 2019 08:23 AM PDT

LIGO has been running for five years, or about one three billionth the age of our universe. I'm amazed that it has already detected ten black hole mergers. Can we interpret this as: 1) there are a LOT of black holes in the universe. 2) the universe is SO huge and mind-boggingly expansive that even rare events are common. 3) there are black hole clusters. or 4) we are seeing mergers from a time when black holes were more common.

submitted by /u/alternatethinking
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Does the volume at which you listen to your headphones impact impact how long it's battery will last? If so how much?

Posted: 24 Apr 2019 03:14 PM PDT

Title says it, I'm curious as to whether listening to a pair of wireless headphones at a certain volume would change the battery life of the headphones and if so how much approximately?

submitted by /u/Inferno_Gear
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How exactly does carbon monoxide work on a molecular level?

Posted: 24 Apr 2019 03:40 PM PDT

From what I know, oxygen needs two electrons to complete its valence shell - but carbon needs four. How would carbon monoxide be stable if the carbon still needs two valence electrons?

submitted by /u/InsertANameHeree
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Do indoor plants (succulents, etc.) improve air quality?

Posted: 24 Apr 2019 12:32 PM PDT

I know they have psychological benefits, but information on whether they provide actual air quality benefits is sparse and inconclusive.

submitted by /u/yourmomsreddithandle
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Do other planets suffer from less or more earthquakes compared with earth?

Posted: 24 Apr 2019 02:29 PM PDT

Recently I saw a news article saying it was registered the first earthquake on mars, and that made me wonder, are there more earthquakes in other planets compared with earth?

submitted by /u/Thatbrownmonster_
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Why doesn't the sun explode at all once?

Posted: 24 Apr 2019 03:43 PM PDT

If the sun is mainly hydrogen and helium and it's burning why does it burn over billions of years? Does it have to do with atmospheric difference? If we ignited a bunch of gas in our atmosphere wouldn't it explode rapidly?

submitted by /u/BoggsMcMuncher
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Can something be isotropic but not homogeneous? Or vice versa? If so, how?

Posted: 24 Apr 2019 05:09 PM PDT

How do we know something "causes cancer"?

Posted: 24 Apr 2019 12:09 PM PDT

How long can seeds last?

Posted: 24 Apr 2019 08:52 AM PDT

Why can't you pull the car door handle while unlocking it?

Posted: 24 Apr 2019 02:56 PM PDT

Title is pretty self explanatory, but why can't/doesn't the door unlock if someone is pulling the handle while you press the button, on the keys for example?

submitted by /u/wabahoo_on_you
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Is there a fractal, which volume approaches infinity and surface area approaches zero as the iterations approaches infinity?

Posted: 24 Apr 2019 07:22 AM PDT

Hello r/askscience, I recently learned about fractals and the menger sponge. As the number of interations approach infinity, the volume approches 0 and the surface area infinite.

Is there another fractal, which behaves the opposite way (0 surface area, infinite volume)?

Thanks for your answers

submitted by /u/Hikatokage
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Do memories take up physical space?

Posted: 23 Apr 2019 10:07 PM PDT

How Earthquakes are formed ?

Posted: 24 Apr 2019 06:48 AM PDT
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Wednesday, April 24, 2019

AskScience AMA Series: Hi! We are researchers from the National Institutes of Health and University College London studying how advances in genetics are affecting our lives and the world around us. In honor of National DNA Day, ask us anything!

AskScience AMA Series: Hi! We are researchers from the National Institutes of Health and University College London studying how advances in genetics are affecting our lives and the world around us. In honor of National DNA Day, ask us anything!

AskScience AMA Series: Hi! We are researchers from the National Institutes of Health and University College London studying how advances in genetics are affecting our lives and the world around us. In honor of National DNA Day, ask us anything!

Posted: 24 Apr 2019 04:00 AM PDT

Each year on April 25, we celebrate National DNA Day, which commemorates the completion of the Human Genome Project in 2003 and the discovery of DNA's double helix in 1953. On this day students, teachers, and the public learn more about genetics and genomics. In honor of DNA Day this year, the Intramural Research Program (IRP) at the National Institutes of Health (NIH) is partnering with the NIH's National Human Genome Research Institute (NHGRI) to bring you an "Ask Me Anything" with three experts on the many ways that advances in the genomic sciences are changing our lives.

Alexander Katz, M.D., and Laura Koehly, Ph.D., of NHGRI, along with Saskia Sanderson, Ph.D., of University College London, will answer questions on the latest discoveries and research endeavors in the field of genetics, including The Genomic Ascertainment Cohort (TGAC), a partnership between the NIH and Inova Health System that aims to gather genomic data from many different sources into a single, searchable system to enable researchers to study the link between genetic variants and individual traits. In addition, they will discuss how knowledge of the human genome and rapidly declining cost of DNA sequencing are affecting our physical, mental, and emotional health, as well as altering our behavior and the ways we interact with one another.

Your hosts today are:

  • Laura Koehly, Ph.D., Chief of the Social and Behavioral Research Branch and Head of the Social Network Methods Section at the NIH's National Human Genome Research Institute.
  • Alexander Katz, M.D., Clinical Geneticist and Principal Investigator, TGAC, NIH National Human Genome Research Institute.
  • Dr. Saskia Sanderson, Ph.D., a Research Psychologist and Senior Research Fellow at the Institute of Health Informatics at University College London (UCL).

Links to some of our papers:

We'll be joining you at 1pm (ET, 17 UT), ask us anything!

submitted by /u/AskScienceModerator
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The last ice age was relatively recent in history, and a huge part of the melt was from North America. How confident are scientists that the grand canyon is as old as accepted, and isn't actually the product of the massive glacial runoff at the end of the last ice age?

Posted: 24 Apr 2019 07:05 AM PDT

[Spectroscopy] When analyzing EM radiation from a star, how many electron transition (and what type) can the spectral information provide?

Posted: 24 Apr 2019 03:38 AM PDT

For example, if there is Ca in the star, can you actually find the spectrum of *all* possible combinations and permutations of say the 1s electron jumping to the d orbital and then jumping back to say the p^y orbital?

And can spectroscopy actually span the entire EM spectrum?

It seems the amount of information that can be garnered from a spectroscopic analysis is mind boggling.

submitted by /u/DailyCloserToDeath
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How do ionic radii influence crystal structure?

Posted: 24 Apr 2019 02:01 AM PDT

Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 24 Apr 2019 08:12 AM PDT

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

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 are Gas Planets’ Moons Formed?

Posted: 23 Apr 2019 10:05 PM PDT

So in my physics class we were discussing Tangential Velocity and orbits and it got me thinking about our moon and how the leading theory involves a large planetary collision with a chunk somehow ending up in orbit.

This is odd because Jupiter, for example, has 79 Moons and it's made of gas and therefore has no possibility of forming a moon via collision like earth did.

Ive done a bit of research and I am a little confused at what I've found. So I understand that Jupiter's outer moons orbit the opposite way of Jupiter's rotation thus pointing to the idea that the outer moons are asteroids that got caught into an orbit. This seems plausible. However, the inner moons are supposedly formed during the gaseous phase of our Solar System!?

This doesn't make sense to me because why would the primordial stew of gasses be attracted to random smaller collections around Juipiter instead of into the single massive collection of gas's forming near it (Jupiter). This also brings up another question! How did all these planets and moons initially get their tangential velocity to maintain orbits when they were first formed from gasses? I'm very confused :/

submitted by /u/Cono9
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What are the pharyngeal slits used for in the human embryo?

Posted: 23 Apr 2019 10:58 PM PDT

If you are at the base of a large mountain range, is there any noticeable or measurable gravitation effects in the horizontal direction toward the mountain center of mass?

Posted: 23 Apr 2019 05:32 PM PDT

The filmmakers behind the DS9 documentary film "What We Left Behind" are sharing an early release screener for backers on Thursday. They've said that the film is "digitally encoded" and "traceable back to you" if stills or video are shared. How is this possible?

Posted: 23 Apr 2019 07:52 PM PDT

I am a student and when i was done learning for my chemistry test i was wondering how people measured atom masses, for example magnesium (Mg) has a mass of 24,3U (according to my textbook) How did scientists scale the weigh of an atom?

Posted: 23 Apr 2019 01:18 PM PDT

When pollen reaches the stigma, how does it get to the ovules?

Posted: 23 Apr 2019 03:03 PM PDT

Why do longer amines have less solubility than shorter amines?

Posted: 23 Apr 2019 10:54 PM PDT

Hi there,

​

I have read in my textbook that "As the length of the hydrocarbon chain of an amine increases, the solubility decreases". Why is this correct? I understand that there are hydrogen bonds and all that, but why would the solubility decrease when the length of the chain increases? Thanks

submitted by /u/chrisunz
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How does the squish squash illusion work?

Posted: 23 Apr 2019 11:35 AM PDT

https://youtu.be/xeGCb9Nxj5w

Above is a link to the "Squish Squash Illusion" What is actually going on in the eyes and brain that makes this illusion work?

submitted by /u/badboyteenagerclub
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Is it possible for there to be more than 2 electrons paired together?

Posted: 23 Apr 2019 05:25 PM PDT

Electrons pair according to Hund's rule where it is stated that only 2 electrons pair together. Is it possible to force electrons to break this rule and if not what prevents it from happening.

submitted by /u/ChimmiChonga00
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What makes your skin red after a sunburn?

Posted: 23 Apr 2019 10:55 AM PDT

How do we know how old a fossil is without carbon dating?

Posted: 23 Apr 2019 07:10 PM PDT

Past 50,000 years carbon dating becomes inaccurate, so how do we determine the age of a let's say 50 million year old fossil?

submitted by /u/Nerd10001
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How *far* does the average tornado travel?

Posted: 23 Apr 2019 10:26 PM PDT

How do gas planets not diffuse into space? Do they have a non-gaseous core?

Posted: 23 Apr 2019 09:46 AM PDT

I've always been confused about how gas planets are a thing e.g. Neptune, Uranus, Jupiter etc. If they are mainly made of gas, then what's stopping the gas that composes them from diffusing into space? What are their cores composed of? How do giant gas balls stay together and rotate on their axis and around the sun?

submitted by /u/Nutmegbread
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Where do we get our gut bacteria from?

Posted: 23 Apr 2019 08:06 AM PDT

As infants, where does our initial set of gut bacteria (and other symbiotic bacteria) come from? Initially we are human cells undergoing mitosis to form human organs and eventually a full human. We get nutrients from our mothers, but to my understanding that is purely nutrients, there is nothing else passed through. So where do these bacteria that are so critical for our existence come from at the start of our lives?

submitted by /u/tacticalBOVINE
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Did the creation of the Panama Canal mess with the eco system of the oceans? IE the combining of two previously separated bodies of water

Posted: 23 Apr 2019 08:03 AM PDT

Is there any evidence that the standard work week affects weather, and if so, how?

Posted: 23 Apr 2019 07:22 AM PDT

Our weather has been very consistent recently (clear and sunny during the week, rained last four Fridays), and I started to wonder whether traffic and factory schedules and patterns had an impact on weather and weather cycles. Or whether this is just an odd coincidence.

submitted by /u/jophus00
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How is the CNOT gate in quantum teleportation allowed to break entanglement?

Posted: 23 Apr 2019 10:11 AM PDT

Perhaps the title is confusingly worded, but I can't think of a better way.

In today's quantum computing class, we discussed quantum teleportation. Specifically, we discussed the following scenario:

  • Alice possesses a particle in the state |Psi> = a|0> + B|1>

  • Both Alice and Bob receive one of a pair of entangle particles, both of which exist in the Bell state |B_00> = 1/sqrt2 * (|0_A>|0_B> + |1_A>|1_B>

  • Alice passes her particles through a CNOT gate, |Psi_a> = W_CNOT(|Psi>|B_A>) (where |B_A> is Alice's part of the entangled pair)

  • Alice then passes her |Psi> particle through a Hadamard gate.

  • The final state of the composite system is then a superposition with equal probability of Alice measuring her pair of particles in any combination, and Bob's particle is a superposition matching Alice's |Psi> particle.

(Side note, this would be much clearer if the subreddit supported LaTeX.)

What I don't understand is how passing Alice's part of the entangled Bell pair can change Alice's particle but not Bob's particle. Isn't the CNOT gate interacting with (i.e. measuring) Alice's particle, and therefore collapsing Bob's particle? Specifically (ignoring constants),

|Psi_sys> = |Psi>|B_00>

|Psi_sys> = (|0> + |1>)(|0_A>|0_B> + |1_A>|1_B>)

|Psi_sys> = |0>(|0_A>|0_B>) + |1>(|0_A>|0_B>) + |0>(|1_A>|1_B>) + |1>(|1_A>|1_B>)

|Psi_sys> = (|0>|0_A>)|0_B> + (|1>|0_A>)|0_B> + (|0>|1_A>)|1_B> + (|1>|1_A>)|1_B>

This last step feels like abuse of notation, considering the entangled nature of the Bell state. Can someone clarify what is happening here?

submitted by /u/picardythird
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How reactive is francium?

Posted: 23 Apr 2019 10:50 AM PDT

I've seen classroom demos of the professor placing alkali metals into water and seeing reactivity increase as you go down the periodic table. I was just wondering what happens if you do this to a significant amount of francium? I know there is a tiny amount on earth at any given time but I've been wondering about this for a long time.

submitted by /u/purpleflower94
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