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What's the third most common element?
- ilovefood 11y agoLove it!!! great share!
- gpvos 11y agoPlease just upvote the post instead.
- maaaats 11y agoPlease just downvote the comment instead. ;)
- sltkr 11y agoI think in cases where the original comment appears to be made in good faith, it's OK to explain what's wrong with it/what to do instead. That's how people learn. (Obvious spam/flames/etc. should just be downvoted, ofcourse.)
- gjm11 11y agoYup. It seems like about half of ilovefood's comments are of the "wow! great article!" type. I'm not sure whether this indicates that comments saying "don't do that" are likely to be helpful or not... (If it were 100%, I'd conclude that it's a would-be spammer's account, building up a bit of history before starting to try to fill HN with spam. But I don't think that's what's going on here.)
- ghubbard 11y agoWhat's the third most common element (in the universe)? tl;dr: Oxygen But it's worth reading the article to learn why.
- raverbashing 11y agoFrom what we can conclude that: water is very common (Of course, most likely not in liquid form)
- lmm 11y agoNo we can't. If it's not molecules, it's not water, and there's nothing here to indicate whether the hydrogen and oxygen are found bound together.
- raverbashing 11y agohttps://en.wikipedia.org/wiki/Water#In_the_universe https://en.wikipedia.org/wiki/Water#In_the_universe While water will break down at high temperatures I would find it surprising that 1st and 3rd most common elements in the whole universe, that readily combine to form water would not result in substantial amounts of water. It's probably like saying we shouldn't find H2 because "nothing says they are found bound together"
- gpvos 11y agoStill can't conclude it from just the data presented here.
- raverbashing 11y agoYou have to explain more than that
- weego 11y agoYou provided a conjecture based on incomplete data as fact, he stated that it's conjecture until additional data to support it is there... the burden in this situation is not on him.
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- jakobegger 11y agoThe graph at the bottom of the post would greatly profit from horizontal gridlines.
- throwaway_yy2Di 11y agoHere you go, https://i.imgur.com/Bgttnqh.png https://i.imgur.com/Bgttnqh.png
- Jugurtha 11y agoNice read, and pretty neat periodic table. PS: People might also like "Atomic Physics and Human Knowledge"[0] by Niels Bohr. It's a quick read (less than 60 pages). [0]: https://archive.org/details/AtomicPhysicsHumanKnowledge https://archive.org/details/AtomicPhysicsHumanKnowledge
- david-given 11y agoStupidity.
- eidyia 11y agoreligious much? at least give an excuse for your comment IF you want people to take you seriously
- evantahler 11y agoSurprise?
- gpvos 11y agoWell, yeah. I thought it was carbon, and I thought it was way ahead of the others. But instead there are actually a bunch of elements vying pretty closely for third position: oxygen, carbon, neon, nitrogen, magnesium, silicium, iron, sulphur. (Although one should keep in mind that the graph is logarithmic.) Note that the graph actually shows the estimated abundance of elements in the solar system (found that on Wikipedia), not the universe or the Milky Way. The article misrepresents that!
- Terr_ 11y agoI thought he was making a Terry Pratchett reference. > The world is made up of four elements: Earth, Air, Fire and Water. This is a fact well known even to Corporal Nobbs. It's also wrong. There's a fifth element, and generally it's called Surprise.
- natejenkins 11y agoWhat caught my eye was the oscillation in the abundancy graph, there is a tendency for even atomic number elements to be more abundant than odd atomic number elements. Looking at the original Wikipedia article leads to the Oddo-Harkins rule http://en.wikipedia.org/wiki/Oddo%E2%80%93Harkins_rule http://en.wikipedia.org/wiki/Oddo%E2%80%93Harkins_rule. There is more discussion on the stability of even vs odd atomic number elements here: http://en.wikipedia.org/wiki/Even_and_odd_atomic_nuclei http://en.wikipedia.org/wiki/Even_and_odd_atomic_nuclei. From the latter link, roughly 60% of stable nuclei have an even number of protons and an even number of neutrons. Only 2% have an odd number of protons and an odd number of neutrons. It would be nice if someone could explain any of the exceptions to the Oddo-Harkins rule, such as the dip at atomic number 44, Ruthenium.
- throwaway_yy2Di 11y agoI don't think that's ruthenium -- that graph has a gap at technetium (Z=43), which has no long-lived isotopes. The line actually joins Z=42 and Z=44. (Might also be confusing that Sn (Z=50) is labelled at the wrong place (Z=48)). edit: here's a modified version, https://i.imgur.com/0iQ6vNX.png https://i.imgur.com/0iQ6vNX.png
- loceng 11y agoHow odd..
- deleted 11y ago[deleted]
- peter303 11y agoalpha fusion (He nucleus) is lower energy than proton fusion
- autokad 11y agowhen you roll 2 dice, you get a lot more evens than odds. i imagine the same principle holds. if an odd (Hydrogen) forms with another odd, you get even. Hydrogen+helium=odd, but helium + helium = even. as the evens outnumber the odds, even more evens are forming with evens.
- solve 11y agoTell me more about the creation of the elements that "come from cosmic rays".
- deleted 11y ago[deleted]
- mrfusion 11y agoI've always wondered how elements produced in past stars end up in our solar system. I wouldn't think the whole universe is getting remixed all the time. It seems like areas stay pretty isolated.
- simonh 11y agoAt the universal scale, we can observer several galaxies in various stages of colliding with each other (1). In fact our galaxy and Andromeda are on course to collide with each other in about 4 billion years (2). Massive stars end their lifecycle in a supernova explosion, which blasts much of their mass off into space. the remaining stellar core either forms a neutron star or a black hole. The mass that is blated off contains many heavy elements formed in the star by nuclear fusion, and contributes to nebula formation. These nebulas coalesce to form new stars and their associated planetary systems. We can actualy see this happening in various places throughout our galaxy, with nebulas in various stages of coalescing and with multiple stars forming within them. Absorbtion spectra tell us about the materials these nebulae are composed of. There is some speculation that heavy elements such as iron are also produced and scattered about in nutron star collisions. (1) http://en.wikipedia.org/wiki/Galaxy_collision http://en.wikipedia.org/wiki/Galaxy_collision (2) http://en.wikipedia.org/wiki/Andromeda_galaxy#Future_collision_with_the_Milky_Way http://en.wikipedia.org/wiki/Andromeda_galaxy#Future_collisi...
- mrfusion 11y agoInteresting. So where did our sun come from? Are you saying it started from a multilight year wide cloud? Why is it 4+ light years from any other stars? Did our sun pull everything out of that radius when it was forming leaving a whole bunch of empty interstellar space?
- simonh 11y agoBear in mind the galaxy is continuously rotating, our sun is orbiting the galactic nucleus, as are the other stars around it. Right now the nearest star is 4 lightyears away, but that's not always the case and it's quite likely other stars have passed ours by much closer than that during it's lifetime. In fact our sun has orbited the galactic core many times; it does so roughly every 250 million years. The sun would have accumulated material from the nebula it formed in as it drifted though it. The stars near us now are not the ones our sun was near when it formed though (except by extemely unlikely co-incidence), as each star is on a slightly different course round the galaxy, like water droplets in a very slowly rotating cyclone. If another star were to pass by very close, it could be disastrous for us as it could severely disrupt the planetary orbits in our system, but that's fairly unlikely and there's no prospect of that happening for many millions of years at least. The space between stars is vast, even by comparrison to the size of stars themselves and their solar systems. EDIT - on that last point, 4 ly is ~250,000 AU (the distance from the earth to the sun). If we asume out solar system is 100 AU across, that's still only 1/2500 the distance to the next star.
- scotty79 11y agoIs big bang necessary for this or does any amount of photons of insanely high energy crystallize in matter in those proportions?
- analog31 11y agoAs I understand it, something like the big bang produces mostly light elements -- hydrogen and helium. Everything else is produced in the stellar fusion machine plus supernovas. So, by the time that the heavier elements are forming, the big bang has been done with and forgotten about for at least, like a microsecond. ;-)
- scotty79 11y agoI was referring to creation of hydrogen, helium and traces of some others like lithium. Thinking about what you said I think necessary condition to get big bang hydrogen/helium ratio is that although there must be very high energy density we must not have too much of gravitational confinement because that would spark fusion and mess up the ratio bringing to closer to what we have currently in the universe.
- gus_massa 11y agoThe Hydrogen-Helium ratio is very related to the details of the Big Bang. From http://hyperphysics.phy-astr.gsu.edu/hbase/astro/hydhel.html http://hyperphysics.phy-astr.gsu.edu/hbase/astro/hydhel.html > Basically, the hydrogen-helium abundance helps us to model the expansion rate of the early universe. If it had been faster, there would be more neutrons and more helium. If it had been slower, more of the free neutrons would have decayed before the deuterium stability point and there would be less helium.
- scotty79 11y ago> If it had been faster ... > If it had been slower ... Isn't the inflation conceived to be as fast and long as necessary so that inputs to baryogenesis give result with hydrogen to helium ratios that are in line with experimental data?
- mrfusion 11y ago(Maybe it was XKCD that gave me the idea?) But I remember thinking it interesting that humans are the chemical/physical process that creates those highest elements.
- Youpinadi 11y agothe "a" element (after div and span)
- gpmcadam 11y agoIt says "it starts with a bang" so I was thinking <!doctype> after <html> and <body> :)
- elros 11y agoI would say `p`, right after `div` and `span`
- stephancoral 11y agoWouldn't <html>, <head>, and <body> be the three most common?
- Jack000 11y agobut they occur only once per page
- BFay 11y agoDid anybody else click on this expecting a DOM element? I was guessing <p>
- Agathos 11y agoWhat are the six most common elements in the universe? H, He, C, N, O, Ne What are the four most common elements in living cells? H, C, N, O (We invited the noble gasses to play, too, but they said something along the lines of, "Go away you peasants you'll mess up our perfect orbitals.")
- arto 11y agoAs for lithium (the third-most abundant element after the Big Bang, at 0.00000001% of nuclei), it so happens I was just reading the James S. A. Corey novel Cibola Burn where it plays a role: "People used to think gold was worth fightin' over, and that shit gets made by every supernova, which means pretty much every planet around a G2 star will have some. Stars burn through lithium as fast as they make it. All the available ore got made at the big bang, and we're not doin' another one of those. Now that's scarcity, friend."
- hga 11y agoNaw, or at least according to what I've been reading lately we get lithium and a number of other light elements from cosmic ray spallation: (https://en.wikipedia.org/wiki/Cosmic_ray_spallation https://en.wikipedia.org/wiki/Cosmic_ray_spallation so it's happening all the time.
- hashmymustache 11y agoReminded me how crazy it is that we're in a time where we've legitimized the fabled goal of alchemic transmutation - we can turn mercury to gold. Turns out the philosopher's stone was a particle accelerator.
- hga 11y agoDon't forget about the incomplete specification problem: You wanted non-radioactive gold for your jewlery and dental fillings? Oops, sorry about that.... (https://en.wikipedia.org/wiki/Isotopes_of_gold https://en.wikipedia.org/wiki/Isotopes_of_gold)