life cycle of a star?
141631
Here is a site that shows the cyle of a star http://www.enchantedlearning.com/subjects/astronomy/stars/lifecycle/\n\nHope it helps you!
216942
Our sun is indeed a star. As a star,it will go through all the phases that other stars go through like BIG BANG and etc. Yes,our sun will explode one day and that day will be in another million or billion years of time. So,don't worry about it now. Worry about your great grandchildren. Anyway i hope that i had answered your question. Take care.
545487
The sun has lived for a long time actually the sun isn't alive but anyway stars usually live for a bout ten billion years.  they know this by looking at the history of other stars and how much they have gone out in the short amount of time  it was being studied. The sun is burning its hydrogen gas so its not a really accurate guess but its pretty close. but you wont have to worry about the sun burning out because you will already be dead for a long time.
62632
Depends on the mass of the star....but for example for a star with mass similar to the Sun..\n\n1. Protostar contraction for roughly million years or slightly less.\n2. Main-sequence for roughly 9 billion years.  In this stage the core is burning hydrogen to helium.\n3. Giant stage.  Where the core that is filled with helium compresses and starts to heat up and make star expand.\n4. Planetary nebula\n5. White dwarf\n\nSome massive stars will burn other elements like helium and carbon and can turn into neutron stars or black hole.  Black holes happen for stars greater than roughly 25 solar masses.
604233
By using spectra. Each element has characteristic frequencies of light that it emits or absorbs. If light from the star is spread out into a spectrum (like a rainbow), there will be dark lines for absorbtion and bright lines for emission. By identifying the chemicals that correspond to those lines, we deduce the composition of the star.
304584
Yes, new stars and new planets can form from the remnants of dead stars.  We can see this process happening, although it is extremely slow, a process that take millions of years.\n\nEven our sun is thought to be a 3rd generation star.  When our sun dies, it will expand to become a Red Giant star, eventually cooling/contracting into a white dwarf, as this happens, a lot of stellar meterial will be released and will float off into space to make new stars in the future.
269272
Starfish (or as they are known by in the Marine Community "Sea Stars") have been known to live 8 years in aquariums, but the actual life span isn't know.\n\nHere is more about Sea Stars:\n\nhttp://en.wikipedia.org/wiki/Starfish
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
480373
stars, planets, comets, meteors
435493
It's mass.  And its not just in star clusters.  Mass is the only major characteristic of stars.  Almost everything else can be derived (temperature, evolutionary track, luminosity) can be determined by their mass.
814106
A neutron star is the "squashed" core of a star that is left behind after the star underwent a Type II supernova. So a neutron star can be born when a star "dies".
559169
Where new stars are being born.
145689
*Poking lordfarhad.rahimi* Please only post a question once...\n\nFar as the universe being unsteady, yes of course it is. That is the nature of the universe, it is not a steady, static thing. It changes and is chaotic. That is part of the beauty of our universe.\n\nNow, as to stars collapsing. Yes indeed they do, that is part of the life cycle.\n\nStars are born in nebulae. Huge clouds of dust and gas collapse under gravitational forces, forming protostars. These young stars undergo further collapse, forming main sequence stars.\n\nStars expand as they grow old. As the core runs out of hydrogen and then helium, the core contacts and the outer layers expand, cool, and become less bright. This is a red giant or a red super giant (depending on the initial mass of the star). It will eventually collapse and explode. Its fate is determined by the original mass of the star; it will become either a black dwarf, neutron star, or black hole.\n\nOur own sun will become a black dwarf in a few billion years...\n\nOn a side note, the universe itself is not collapsing, never fear. It is expanding and getting larger all the time.\n\nI've added some links that have great diagrams of this fascinating topic below.
685084
You can try to count the stars, but there are as many stars in the Universe as there are grains of sand on the beach.  It would be a very difficult task and take millions of lifetimes to complete.  Sorry.
403997
Astronomy:The life of Stars. You can get some awesome pictures for that and there is plenty to write about, like (i am not completely sure about this number)did u know that light takes almost 250,000 years to travel from the center of our sun to the surface.\n\nhttp://en.wikipedia.org/wiki/Star
867115
there is a regular EXPANSSION, BIRTH of new stars, Death of the stars.............. \nAnd so many.\nand you are asking any changes!!!!!!!!!!!!
57934
Photometric (O-C) diagrams are the tool of choice for representing period variability. For eclipsing stars the ordinate in such diagram is generally formed from observed (O) timings of minimum light from which is subtracted the time calculated ( C ) from some convenient pdarkredictive ephemeris. The abcissa is conventionally the cycle count of orbital revolution or some other measure of time