If all the stars are made from hydrogen then where this hydrogen in the universe came from?
812826
the fundamental particle is hydrogen \n\nso all the stars r made of H2\n\nthe hydroen atoms undergo nuclear fusion to form helium \n\nn other higher elmts\n\nthat's wat the secret of universe
514532
We are all related.  You will see scientists, who mainly believe in the big bang theory, will often describe us as "stardust".  The reason for this is that when planetary nebula are being created, and a star results, the leftover matter from the new star is what planets condense from.  They are made of the same basic materials.  \n\nIn addition, every basic element on the periodic table from hydrogen to iron (including carbon; e.g. "carbon-based life forms" such as us) is naturally produced inside the sun, and every larger element can be produced from the same basic ingredients by other processes.  \n\nIt is no coincidence that we (and everything else) are made of the same elements as the rest of the solar system and much of the universe.
861436
The universe consits mostly of dark energy (95 percent) with about 25 percent of that being dark matter. Then, about 4 percent is free hydrogen and helium. Stars, about .5 percent, neutrinos, .3 percent and heavy elements (metals, iron etc.) about .003 percent. Further more, the density of the universe has been calculated to about one hydrogen atom for every cubic meter of space. So as you can see the matter that is visible, makes up a very miniscule amount of the universe.
689695
All stars are made mostly of hydrogen, with a reasonable amount of helium thrown in for good measure.  Trace other elements exist as well, and since astronomers are so biased toward the light stuff (hydrogen and helium are the smallest atoms and therefore the lightest elements), they refer to anything heavier than helium as a “metal.”  The proportion of a star made up of stuff heavier than helium is called its “metallicity.”  The Sun’s metallicity is about 1.6% by mass.\n\nIn galactic terms, the Sun is considered “new.”  Yeah, it’s some 4.5 billion years old, but the same way anything heavier than helium gets dubbed a metal, the Sun is considered new—because it’s a second- (or maybe third-) generation star.\n\nY’see, when the Universe formed, hydrogen and helium were pretty much the only game in town, plus a bit of deuterium or lithium.  A star forming out of this stuff could have a metallicity just one millionth of the Sun’s!  To get more “metals,” the first generation of stars (i.e., the old ones) had to form, cooking up heavier elements inside their thermonuclear cores.  Some fraction of those stars went kablooie (in the form of supernovae and other exotic events), enriching the interstellar medium with heavy elements.  \n\nWhen a second (or third) generation of stars formed from this enriched interstellar medium, they had much higher metallicities.\n\nWe can find evidence for the presence of “metals” when we look at the light from individual stars or even entire galaxies.  Those elements show up as absorption features at very particular wavelengths of light, and astronomers can read that collection of “absorption lines” like a fingerprint.\n\nSo when we look at elliptical galaxies, we see evidence for very few elements heavier than helium, so we infer that the stars are “old”; when we look at most spiral galaxies, we see evidence for a metal-rich environment, so we understand the stars to be “new,” in the sense that they are second-generation stars that have benefitted from their predecessors” nuclear fusion and element production.\n\n\nRyan Wyatt\nRose Center for Earth & Space\nNew York, New York
529556
The elements are formed in the Universe in three different places and times.\n\n1) In the three first minutes after the Big Bang protons and neutrons were formed. Roughly a quarter of those combined into helium, deuterons (heavy hydrogen) and a tiny bit of lithium.\n\n2) Stars like the sun are made of 75% hydrogen, 24% helium and 1% of other stuff. Their cores are hot enough to fuse hydrogen into helium. When the hydrogen in the core is exhausted the star goes through the red giant state in which it fuses helium into heavier elements like oxygen, sulphur all the way up the periodic system upto iron.\nThe smaller stars blow their outer layers into space.\n\n3) The bigger stars however, say 5-8 times the mass of the sun explode. These are supernovas. During this explosion a large part of the energy is liberated in the form of neutrinos.\nAn incredible amount of neutrinos, in fact. These particle are capable of transforming elements into others as they can change neutrons into protons. These reactions produce the elements heavier than iron.\n\nHow do we know this? \n\nAll three processes have been modelled. These models predict abondances for the elements in the universe. Those can be mesured are turn out quite close to the predictions.
751337
There are two types in the solar system: \n- the terrestrial or rocky planets: Mercury, Venus, Earth, and Mars, which are composed primarily of rock (Si and C oxydes) and metal (Fe, Ni). \n- the gas planets: Jupiter, Saturn, Uranus, and Neptune, which are composed primarily of hydrogen and helium, just like the sun.\n\nYou notice immediately that there is a difference in size between the two groups. And that explains everything: the sun and therefore the original dust cloud which was at the origin of the solar system, contains 75% hydrogen, 24 % helium and 1% other stuff. \n\nThe sun swept clean the inner region of the solar system and the planets were small. To small to held on to the volatile gases H and He. Those escaped and rocky bodies remained.\n\nBut farther away from the sun, the planets themselves cleaned up space. They could grow much bigger, and kept most of their H and He.
52498
Lighter elements (like hydrogen and helium) have been present since the beginning of time, and we see them largely in stars undergoing fission and fusion processes.  It is THESE processes (combustion of hydrogen and helium in a star) that CREATE heavier elements.\n\nThis process takes time.  We can only get elements up through iron before we need suns to take over and start crafting heavier ones.  That is why we see predominantly helium and hydrogen... it takes a while to make the rest.
444152
Nature is all about entropy or conservation of energy.  Stars of which Our Sun is one start their life as large balls of Hydrogen gas.  Due to the friction of the untold number of molecules  moving about, heat is developed- just like rubbing Your hands together.  The inside temperature of the Sun is about 2 million degrees.  It takes more energy to maintain 4 atoms of hydrogen than it does for one Helium.  With all the heat in the star's core it is possible for the hydrogens to form a helium by the process of nuclear fusion.  6 hydrogens take part in the reaction but two are recovered so the net result is 4h>1He.  This reaction results in the saving of 0.6% energy which works its way to the surface and radiates out into space.  Within the Sun it is estimated that about 745,000 tons of H are converted every second.  This number varies a bit when one reads the literature, but whatever the actual number is it is huge.
455949
everything in this universe moves. stars are parts of galaxies. for example our sun is a part of the milky way galaxy. we are in the sagittarius arm of our galaxy which rotates about its centre and as we are in one of the outer arms as the galaxy seems to rotate the sun along with its nine planets revolves around the centre of the galaxy. this is exactly what happens in other stars and star systems. secondly  all stars are round not to mention, every heavenly body is round because gravity makes them round. and the shape we concieve is just because of the phenomenon of scattering of light as the light from the stars passes through various layers of the atmospheres of different densities
1061521
Allow me to confuse you even more. \n\nTo begin with, the universe is not the result of an explosion. An explosion takes place inside something else, like a building, earth's atmosphere, etc.,  There is absolutely not one single shred of evidence that our universe began inside anything else.\n\nIn the first few instants of the universe there was nothing but spacetime and pure energy--no matter (mass) of any kind, including hydrogen. It wasn't until the universe was about 3 minutes old that the first low-mass atomic nuclei began to form, and another 400,000 years would pass before neutral atoms formed. Finally, after that 400,000 year point, the universe had cooled enough that hydrogen could first appear to fill the already existing spacetime volume of the universe.
515033
The most abundant element in the universe is hydrogen.  Nebulae are made up most of that and "dust".
271980
The Earth is in the Solar system, the solar system is in the Galaxy and the galaxy is in the Universe AKA outer space. The answer to your question is not known, some say the Universe is the end of that line, stuff is made of atoms, atoms are made of protons, neutrons and electons, protons, neutrons and electrons are made of quarks, which are made of (I think) gluons, huons and mesons. I think that their is another universe, say a ten or eleven dimensional universe, that holds infinitely more four dimesional universes, like ours, this is part of string theory.
552214
Seeing as our solar system must have been formed from the last dying sneeze of a star (as there are very heavy elements that couldn't be present otherwise), thats where we came from. We are basically star snot.
319086
First, our sun has a long time to go before it could possibly become a supernova, not for billions and billions of years, so don't worry about it, if you were worrying. OK?\n\nNow, the way a star burns is by fusion, which is building up heavier elements by fusing atoms of lighter elements together. The typical start starts out as hydrogen, and it fuses the hydrogens together into helium. \n\nWhat happens when a star runs out of hydrogen? It starts fusing the heliums together into heavier elements. In order to begin this process, the star has to contract, to squeeze everything together to make the core temperature hotter. \n\nNotice that when the star began to run out of hydrogen, it cooled off a little. So the temperature of the star fluctuates. Its size fluctuates too, since the heat energy partly counteracts the gravity that holds it together.\n\nSo, the star cools off a little, it contracts, and we call this a pulsating or variable star. (This is somewhat of an oversimplification; there are different types of variable stars. But I am ignoring them for purposes of this illustration.) Then the star begins fusing helium, and heats up again. The star expands. \n\nThe outer surface of the star explodes away in what we call a nova-- not a supernova, yet. Some of the gas rushes away and may form what is called a nebula, a cloud. some of thee nebulas give off pretty colors, because, just like a neon sign, the gas in them is excited by the energy of the star and glows.\n\nSo, after repeated cycles of this, and bazillions of years, the star is exhausted. When the star gets iron in its core, there is no turning back. You can't fuse iron into anything. \n\nBut, you say, what about those elements that are heavier than iron, like gold and mercury and uranium? Ah, I'm so glad you asked about that. That is where the supernova comes in. \n\nA supernova is the death of a star. A nova flares up and puts out lots of energy, but the supernova puts out as much energy as the star might have put out over its entire lifetime! The last time there was a supernova in our galaxy (the Crab Nebula was formed) in 1054 AD. The Chinese were the only ones whe were doing much astronomical observation then. \n\nBut it was visible in broad daylight! From LIGHT YEARS away!\n\nWhat happens is this: the star begins to contract one final time. Most of the star blows away, making a really, really impressive nebula. All the elements that were built up in the final explosion-- all the heavy elements beyond iron-- get flung out into space, where they might meet with other elements and form planets and things.\n\nWhat happens to the rest of the star? One of three things, depending on how big it is. If it is little, it may form a white dwarf, a little star that is not so big but is now mostly hydrogen and helium and will last a long time. I think they are supposed to expand into red giants when they are about to burn out, but I don't remember for sure. \n\nIf the star is medium sized, it may become a neutron star. It is no longer buring with fusion like a regular star. The nuclear particles in its core are squeezed together so that protons and electrons have lost their identities and everything is neutrons. This is as solid and dense as matter can get, neutronium. It has an incredibly strong magnetic field, bazillions of times anything on earth.\n\nThe star's axis of rotation may not line up with the magnetic poles (just the way Earth's magnetic poles are not right at the true north and true south poles.) If this hapens, and the magnetic poles are pointed in the right direction, then every time it points our way, we see a little 'flash' of magnetic energy, and we call these 'pulsars'. The first time anybody detected them, they thought they were radio signals from people in space, because they were so regularly-spaced. It is a good thing there are no pulsars near Earth, because the flashes of intense magnetic fields would fry us lik
402161
I dont know. Stars forming quickly doesnt disprove big bang. the bang did not make stars. I guess it spread the compounds that stars form out of around. I also wonder at the 'quality' of a star that forms really quickly. But everyone knows big bang is hooey. Odin make the universe from the body of the slain frost giant, Ymir. They should teach that in school.
2691
"Where?" requires the existance of space. There was no space before the Big Bang. We cannot even talk about "before", since there was no time, either. It's counterintuitive and cannot be assessed in a normal state of mind - logic won't help here, even a twisted one. Science struggles to answer the questions regarding the very beginning. What is known, however, is that right after the Big Bang there was no hydrogen - it was too hot for it to form. First quark-gluon plasma, then protons and neutrons, then hydrogen atoms. So it took some time, though, given the age of the Universe, it occurred almost instantaneously.
377820
The Sun is a ball of plasma with a diameter of 1.392 million km (864,950 mi) and a mass of about 2.0×1030 kg, which is somewhat greater than that of an average star in the Milky Way galaxy. About 74% of its mass is hydrogen, with 25% helium, and the rest made up of trace quantities of heavier elements. The Sun is about 4.6 billion (109) years old and is about halfway through its main sequence evolution, during which nuclear fusion reactions in its core fuse hydrogen into helium. About 5 million tons of matter are converted into energy within the Sun's core every second, producing neutrinos and solar radiation. In about 5 billion years, the Sun will evolve into a red giant and then a white dwarf, creating a planetary nebula in the process.