what are the stars and what are they made of?
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They are made of hydrogen.  There's so much gravity at the core of a star that it compresses protons and electrons from other hydrogen atoms and fuses into helium.  The reaction produces a tremendous amount of energy that we see as light.
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sun....its a star btw but there are stars bigger than the sun
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The conversion of light elements into heavy elements, hydrogen into helium and on right up to iron, by atomic fusion. This is how a star shines. When the iron stage is reached the Sun has run out of fuel and the equilibrium between thermal forces and gravity is lost and gravity wins, resulting in the collapse into a white dwarf after going Nova and spreading its heavy elements into space. That's right we are all made of star stuff! JULES
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milky way is our own galaxy.sThe compositions of stars are determined through spectroscopy. Spectroscopy is the study of something using spectra. Recall from the electromagnetic radiation chapter that a spectrum is what results when you spread starlight out into its individual colors. By noting what absorption lines (or sometimes, emission lines) are present and their strengths, you can find out a tremendous amount of information. Stars have absorption lines patterns similar to the Sun. This means that they are composed mostly of hydrogen and helium with traces of other elements. \n\nFrom these absorption lines you learn some important things beside the star's composition: \n\nStructure of stars: From the simple fact that you see absorption lines in most stellar spectra, you know that the stars must have a hot dense part that produces a continuous spectrum and an outer layer, or atmosphere, made of cooler, low density gas. The general trend is density and temperature of stars decreases as the distance from the star's center increases. The hot dense part is also gaseous because of the extreme temperatures. Stars have no molten rock in them like the interiors of some of the planets. \nmass of stars:\nTo determine the masses of stars, Kepler's third law is applied to the motions of binary stars---two stars orbiting a common point. The greater the combined mass of the two stars, the greater the gravity acceleration is, and, therefore, the smaller their orbital period. A majority of the several hundred billion stars in the Galaxy are in a system with two or more stars orbiting each other. Usually the binary stars are spectroscopic binary stars. A spectroscopic binary system is two stars orbiting a common point at too great a distance away from us to resolve the two stars individually, but whose binary nature is indicated in the periodic shift of their spectral lines as they orbit around each other. Spectroscopic binary stars are used because (a) there are a lot more far away stars than nearby ones and (b) more importantly, you can easily measure their speeds from the doppler shifted lines. \ncolour of star:\nHot stars appear bluer than cooler stars. Cooler stars are redder than hotter stars. The ``B-V color index'' is a way of quantifying this using two different filters; one a blue (B) filter that only lets a narrow range of colors or wavelengths through centered on the blue colors, and a ``visual'' (V) filter that only lets the wavelengths close to the green-yellow band through. \nA hot star has a B-V color index close to 0 or negative, while a cool star has a B-V color index close to 2.0. Other stars are somewhere in between. Here are the steps to determine the B-V color index: \n\nMeasure the apparent brightness (flux) with two different filters (B, V). \nThe flux of energy passing through the filter tells you the magnitude (brightness) at the wavelength of the filter. \nCompute the magnitude difference of the two filters, B - V. \n\nok thats all,
785520
go to http://moon.google.com and zoom in all the way.  you'll see what our moon is made of.
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STARS AND NEBULAE.\n\nMost of the things you can see in the night sky are stars: a few thousand are visible to the unaided eye. A star is a hot ball of mostly hydrogen gas; the Sun is an example of a typical, ordinary star. Gravity keeps the gas from evaporating into space, and pressure due to the star's high temperature and density keeps the ball from shrinking. In the core of the star, the temperature and densities are high enough to sustain nuclear fusion reactions, and the energy produced by these reactions works its way to the surface and radiates into space as heat and light. When the fuel for the fusion reactions is depleted, the structure of the star changes. The process of building up heavier elements from lighter ones by nuclear reactions, and adjusting the internal structure to balance gravity and pressure, is called stellar evolution. \nLooking at a star through a telescope can tell us many of its important properties. The color of a star tells us its temperature, and the temperature depends on some combination of the star's mass and evolutionary phase. Usually, observations also allow us to find the luminosity of the star, or the rate at which it radiates energy as heat and light. \nAll stars visible to the unaided eye are in our galaxy, the Milky Way. The Milky Way is system of roughly 100 billion stars, along with a great deal of interstellar material. The galaxy is shaped like a flattened disk embedded in a round, faint halo. Gravity keeps the stars from drifting away, and the motions of the stars keep the system from falling in on itself. The Milky Way has no distinct edge - the distribution of stars tapers off gradually with increasing distance from the center. The SDSS detects stars more than a million times fainter than can be seen with the unaided eye, far enough to see the outer structure of the Milky Way. \nStar Colors and Luminosities: The H-R Diagram\nAstronomers often make plots of the luminosities of stars compared to their colors. The first such charts were made in the early twentieth century, when astronomers took spectra of thousands of stars, then placed the spectra into a sequence based on the appearance of several different features. The classes of stars were given different letters as names; in order of decreasing temperature, they are OBAFGKMLT. The hottest stars are class O, while the coolest are class T. Two astronomers, Ejnar Hertzsprung and Henry Norris Russell, independently started to wonder what would happen if they compared stars' luminosities to their spectral classifications (or, alternatively, to their temperatures). They knew that some stars were hotter and more luminous than the sun, and that others were cooler and less luminous. Hertzsprung and Russell found that 90% of the stars fell into a narrow band they termed the "main sequence." Today, we call this type of plot a Hertzsprung-Russell (or H-R) diagram. \nAstronomers further divide each letter into ten categories from 0 to 9, with 0 being the hottest star in that spectral class and 9 being the coolest. So, a B1 star is hotter than a B2 star, and a B9 star is hotter than an A0 star. Our own sun is at the "hot" end of the G range with a surface temperature of 5,770° K; therefore, it's called a G2 star. \nSpectral classes give us a convenient way to refer to most types of stars - from O0, the hottest at over 25,000° K, down to T9, the coolest failed stars at 1,000° K. Each spectral type of star is associated with a specific color: all G-type stars like the sun are yellow, all M-type stars appear red, and all B-type stars are bluish. Thus, this system of letters and numbers tells us where a star is on the horizontal (color or temperature) axis of the H-R diagram. \nTwo alternative systems tell us approximately where on the vertical (luminosity) axis a star can be found. One system uses absolute magnitude, a measure of luminosity derived from the apparent magnitude, or brightness of the star
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check this site...\nhttp://www.bbc.co.uk/science/space/stars/index.shtml
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Planets\nStars\nGases\nDark Matter\nDark Energy\nRegular baryonic matter\nMeteor Rocks?
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Is the sun a planet?  Is the moon a star?  Is the earth yellow and full and made of cheese?
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what is the atom made of and explain how they work?
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I wanted to say that Quark stars are the stars in the constellation of Donald the Duck, but I really don't know what quark stars are.\n\nMaybe they are stars made up of the subatomic quark particle, just as a neutron star is made up of neutrons.
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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
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There are lots of different types of stars, all with different 'lifespans'. Ours is about 4.5 Billion years old and should 'live' to the ripe old age of about 10 Billion years old.
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The protons and electrons formed into stellar bodies. The stellar bodies converted the hydrogen into helium, carbon, nitrogen, and some other lighter elements.   \n\nStars with a mass of more than 5 solar masses are subject to becoming supernova--a massive stellar explosion.  The energy produced by that explosion produced all of the heavier elements and distributed them throughout the galaxy where they were captured by other gravitational fields.
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planets, stars, and quasars
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Our Sun is a star and is thus made of the same materials (in general) that the rest of the stars are.\n\nBut because of different ages and environments, there are probably no two stars that are exactly alike.
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no...stars are not planets, they are comprised primarily of extemely high and volatile gases that burn without oxygen.