How is light seen from the stars, related to Newton's Particle theory?
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Isaac Newton allowed sunlight from a small, circular hole to fall on a prism, producing a rainbow of color. Although the production of a rainbow by a clear crystal was known to the ancients, it was Newton who showed that the colors did not originate in the crystal, but rather were components of sunlight. This array of colors he called a spectrum. \n\nHere is how the great man explained it: \n\n"And so the true Cause of the Length of that Image was detected to be no other, than that Light is not similar or Homogenial, but consists of Difform Rays, some of which are more Refrangible than others." \n \n\nIn addition, Newton was able to produce a spectrum from white light and then recombine the spectrum colors to get the white light back again. \n\nYears later, in Opticks, Query 29, he gave the following mechanism for the fact that the colors refracted from the greatest amount (violet) through blue, green, yellow, orange (which he does not mention) and to the least amount (red): \n\n"Nothing is more requisite for producing all the variety of Colours, and degrees of Refrangibility than that the Rays of Light be Bodies of different Sizes, the least of which may take violet the weakest and darkest of the Colours, and be more easily diverted by refracting Surfaces from the right Course; and the rest as they are bigger and bigger, may make the stronger and more lucid colours, blue, green, yellow, and red, and be more and more difficultly diverted." \nThis explanation is a particle-based one: light particles are of different sizes.
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The Indian scientist Subramaniam Chandrashekhar put forth a theory on the fate of stars in the 1940s. He proposed that a star which is anything upto 1.44 times the solar mass would eventually become a white dwarf. Any star more massive than this one would meet its end either as a nova, a supernova, or ultimately a black hole. \n\nSo according to this theory, which is consistent with the mathematics of general relativity and quantum theory, the sun is most likely to end up as a white dwarf and not as a black hole.
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Greetings,\n\nYou will sometimes see pictures of stars with points, reference to the link below.  The gentleman who took the picture placed string in a cross-hair pattern over the objective (the opposite end from the eyepiece) to make the points of the stars.  When he was asked why he does this Mr. Russel stated that he just like the way it looked.\n\nThe points on stars in most photographs are generally derived from either slight overexposure or the telescope being out of collimation slightly.\n\n-matt
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There was a problem with his theory. See the rest of the article at:\n\nNewton's aether model\nFrom Wikipedia, the free encyclopedia\nhttp://en.wikipedia.org/wiki/Newton's_aether_model\n\n"In his book Optiks Isaac Newton described a model that attempted to unify descriptions of light, matter and gravity by describing that both the action of gravity on light and the action of matter on light as effects of variations in lightspeed relate to the density of an underlying aetherial medium. This is referred to as Newton's aether model.\n\nNewton described light as starting to bend before it reaches the boundary of an air/glass surface, and related this deflection towards the region of greatest density to the tendency of paths to be deflected towards a gravity-source (again, to a region of greater mass-density). According to the model, particles and waves would be deflected in the same way, matter could be said to be "refracted" by the lightspeed gradient associated with gravity. Newton's postulated light-corpuscles - and the associated "wavelike" effects that he suggested were responsible for steering them - would be deflected in the same way. In modern language, we can say that Newton's aether model was an early attempt at a "geometrical" theory of gravity, or a curved-space model."\n\n"Critically, Newton had mistakenly inverted the relationship between lightspeed and refractive ability: he thought that light had an affinity for regions of higher rather than lower lightspeed. This meant that instead of saying that the aether was the gravitational field and/or the mass density (as with general relativity, Einstein 1920), Newton had to say that his medium was progressively displaced by the gravitational field and by matter, which was a less satisfying concept."
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Stars are big fiery balls of gas. Essentially the gases cluster together and become stars through gravity and fusion. It's a rather complicated process; check the link below for a more detailed explanation.\n\nStars appear to be in our sky because they are in space. Most stars appear to be small points of light, although many of these stars are smaller than our sun. The sun simply appears larger because it is much nearer to the Earth.
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look at Newton for example.  He may not have had a complete theory, but a lot of it is still valid.  \n\nNewton has been modified by einstein. but this is only in the case of very very massive objects (the size of the sun) and very fast moving objects (.7 c and up or 10^8 m/s, very very very fast).  \n\nBut we do not encouter those things in day to day life... infact you will only encounter that limit in stellar physics and particle physics.  \n\nWhen you build a rocket and launch it you are using purely newtonian mechanics.  \n\nThere have been methodes discoverd that make the calculations easier in many situaitions, but for most situations you will use newtons force laws instead of, say, the lagragian equations of motion.  \n\nThis is the same is all well developed feilds.  \n\n\nAlso a bunch of these non symplified theorys that are technecly correct are just too difficlut for just any one to understand.  If you wish to use lagrages or hamoltons equations of motions you need to know differntial calculus.  and you need to be rather good at it.  on the other hand you can do newton with elementry calculus, or even just algebra.  \n\nAlso just the concepts are difficlult to understand.  We can all imagine electrons traveling around the neucleus like planents around the sun, but it is much more difficlt to explain that electrons are not particals but they are waves and they tend to exist in a reigion of space moving around, but because they exist every where they have no change in momentum, and for this reason they exist with out giving off radiation.  \nBut once you understand the first theory, then you can start to modify the picture and try to understand the way things really are.  Which is actualy impossible because the particals exist in a dimention that we can not see, and act in a way that we can not understand.
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the theory that light, and all electromagnetic radiation (radio waves, x-rays, microwaves) travels as a wave, like the ripples on a plucked string. these waves look like sine and cosine graphs.\n\n\nthis was proved to be an incomplete picture by eistein's analysis of the photoelectric effect, for which he won the nobel prize. this showed light was in fact made of particles called photons. however, quantum wave theory now tells us that all matter is both a particle and aa wave; the matter is contained in a particle, but the location of the particle is determined by a wave.
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The answer is no. Isaac Newton had assumed that light was made up of numerous small particles, in order to explain features such as its ability to travel in straight lines and reflect off surfaces. This theory was known to have its problems; although it explained reflection well, its explanation of refraction and diffraction was less pleasing. In order to explain refraction, in fact, Newton's Opticks (1704) postulated an "Aethereal Medium" transmitting vibrations faster than light, by which light (when overtaken) is put into "Fits of easy Reflexion and easy Transmission" (causing refraction and diffraction). Newton believed that these vibrations were related to things like heat radiation, saying:\n\nIs not the Heat of the warm Room convey'd through the Vacuum by the Vibrations of a much subtiler Medium than Air, which after the Air was drawn out remained in the Vacuum? And is not this Medium the same with that Medium by which Light is refracted and reflected, and by whose Vibrations Light communicates Heat to Bodies, and is put into Fits of easy Reflexion and easy Transmission? \nThe modern understanding, of course, is that heat radiation is light, but Newton considered them two different phenomena (believing heat vibrations to be excited "when a Ray of Light falls upon the Surface of any pellucid Body"). He wrote that "I do not know what this Aether is", but that if it consists of particles then they must be "exceedingly smaller than those of Air, or even than those of Light: The exceeding smallness of its Particles may contribute to the greatness of the force by which those Particles may recede from one another, and thereby make that Medium exceedingly more rare and elastick than Air, and by consequence exceedingly less able to resist the motions of Projectiles, and exceedingly more able to press upon gross Bodies, by endeavoring to expand itself."
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There is a surprisingly simple answer to your great question: Each month we see different stars, so to answer for a specific night of the year at your specific location on Earth depending on your eyesight and how bright the city lights around you are might be hard to pin down. \n However there is a magnitude scale that astronomers use to describe how bright objects in the sky are. Without getting into details on how that works, the average human being can see down to about magnitude 6 ( brighter objects have lower magnitude until you reach zero. Then even brighter objects use negative numbers for their magnitudes which is a bit weird, isn't it?) Therefore, all you have to do is get a map of the whole sky showing anything brighter than magnitude 6 and count the stars. If you are fortunate to be away from bright city lights and you can see the Milky Way, you would be really surprised to know that you can only see about 6,000 stars. That's the number of stars above magnitude 6 in the entire sky.
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The distances to stars closer than about 150 light years can be measured directly by use of parallax.  The position of the star against background stars is measured at times 1/2 year apart, and then it is a simple mathematical procedure to determine the distance (you have a side and two angles of a triangle--the angular distance the star appears to move at it's distance over 1/2 year equals 186 million miles-the diameter of the orbit of the earth).  \n\nStars farther than that cannot be measured directly.  But, by use of knowledge about how bright a star should be (on average) for it's spectral type (which loosely is governed by its mass) an estimate of its intrinsic brightness can be made, and then by looking at how bright it appears, it's distance can be estimated.\n\nCepheid variables are used, as well, but mostly to determine the distances to groups of stars and of other galaxies.  Incidentally, the North Star (Polaris, or Alpha Ursa Minor) is a cepheid variable.\n\nNovae and supernovae tend to have average intrinsic brightnesses, so their apparent brightness in, say, a distant galaxy, tells us (within limits) it's distance.\n\nRed shift is used for objects outside our galaxy because the amount of red shift within our galaxy would be extremely small (it increases with distance) if it were not totally overcome by the gravity of the galaxy.
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Interesting. I vaguely remember a "great attractor" from chaos theory, but what I find when I look it up now is that it refers to a cluster of galaxies, "in the direction of Centaurus and Hydra" where nobody is sure why they're grouped like that.\n\nHere's a direct quote from another source though which I think directly addresses what you're asking about: The galaxy rotational problem refers to the phenomenon of the descrepency between the observed rotational motion of the matter of the galactic disc from the predictions of Newtonian dynamics. (See links below and search for "12.25.I".)\n\nI think in layman's terms what they're boggling about is the "bar" shape that occurs in most galaxies, our own apparently included. A recent issue of Scientific American had a very good theory on how that occurs and why.\n\nIf I'm getting the gist of it right, they're not sure why clusters of stars occur in a semi-pinwheel pattern, since based on observed mass there simply isn't enough to cause such a structure to form or remain stable.  The theory in SciAm had something to do with a coincidence of travelling wave patterns rather than any deep dark mysteries of physics, filiments, or anything else.\n\nSee http://www.sciam.com/, October 2005 issue, p. 43, "Ripples in a Galactic Pond." Very nice article and they explained it more clearly than anything I could put together.
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Well it's impossible to see stars when the sun is up, and Venus is the only planet visible during the day, so there is no way all those bodies could have been visible at the same time. There might have been some sort of alignment, but it would only have been calculated, not observed.
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Brightness as seen on earth is called Magnitude.\nBrightness as would be seen from orbit around star is called Luminosity.
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Stars are like our Sun. Not comets at all. Comets are dirty, big snowballs that have no light at all. The twinkling comes from heat radiating from earth which makes the light spectrum shift in different colours. Symbols that represent something doesn't often look like the original. Take the symbol for a heart for example. But it's easy! :) Try to draw a immensly huge boiling, burning piece of gas that throws tons of particles out from it in lightning speed and see if anyone understands what you drew. Now try to make it into a character that you can type on a keyboard :)
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Motion towards or away from the observer. This motion in effect changes the wavelength of the light emitted by the star, and it's wavelength that determines the color of light.\n\nA picture is worth a thousand words, so check the animated graphics at this website:\nhttp://www.colorado.edu/physics/2000/applets/doppler.html\n\nNOTE..!  The graphics at the website are for sound waves, but light waves behave the same way.
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when the light from the stars enter the earth's atmosphere, the light wave bends and refracted until it reach our eyes. So because it is refracted, when we look at it, it seems to be twinkling.
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Our eyes perceive energy in the visible light range that is either emitted from a source, or reflected off an object.  In space, the light sources are stars, like our Sun.  Objects like planets and comets and asteroids and dust, reflect the light emitted by the stars.  Since space is a vacuum, there isn't anything to reflect the light, therefore it is black.