formula about magnitude betwen diameter of galaxy?
469609
very unclear question
625630
How do astronomers measure the radius of a star?\n\nIn order to find the diameter of a star you really need three pieces of information about the star 1) distance 2) brightness 3) and color \n\nStep 1: We can figure out the total power output of the star by knowing its brightness at Earth and its distance. \n\nStep 2: Figure out the surface temperature. The universe really gave us scientists a lucky break because stars are fairly predictable objects. What I mean is that, for most stars once we know one property of the star we can generally figure out everything else we want to know about it. This is because stars behave like "black bodies". This is a physics term which describes how an object of certain temperature glows at different wavelength (thus influencing its color). Most ordinary matter resembles a black body (has nothing to do with being black, it's just terminology). You probably already have an intuitive understanding of this from your everyday experience. For example, when you heat up an object, at first it might start to glow red. And as it gets hotter it might start to glow yellow, blue, and eventually white. Because stars approximate black bodies very well, by knowing the color of the star we can figure out what its surface temperature is quite accurately. \n\nStep 3: Another great thing about black bodies is that, for any specific amount of surface area we can predict exactly how much light it will radiate (hotter objects are brighter). And since we already know the temperature and the total brightness of the star we can figure out its surface area, and thus it's diameter :)
247410
There are different formulas for different shapes. This page has a list of them: http://www.math.com/tables/geometry/volumes.htm
1090272
11038.509198867 kph.\n\nThe math: a circular geosynchronous equatorial orbit has a radius of approximately 42,164 km (from the center of the Earth).  To get the diameter of the orbit,  pi * 2 * 42164, or 264924.2207728 km diameter for the entire orbit.  Divide by 24 to get the distance traveled in one hour, 11038.509198867 kph.
158836
The Milky Way galaxy, our galaxy, is 80-100 thousand light years in diameter, and about 3000 light years thick.\n\nA light year is the distance light travels in one year, so it is a measure of distance and not time.  One light year equals about 5,878,499,810,000 miles.
970313
r=radius\nd=diameter\n\n1 C=2r(pi)\n2 C=d(pi)\n\n(Same thing because 2r=d)
913686
This is a simple ratio problem. The equation would be Dgalaxy/Dearth=Dearth/x so x=(Dearth)^2/Dgalaxy. Asssuming a parsec is 3.6 light years, and a light year is 5.87 trillion miles and the diameter of the Earth is 8,000 miles, then the Earth would be 0.001 millimeter or one micron in size, which is the size of an average bacterium, maybe? Very cool. Oops! I re-did my calculation and I see that I made a factor of ten error. The correct answer is about 0.1 microns, or the size of some viruses. But tell me how you would make such a model of the Earth?
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assume 0.1mm3\n6.02e22 mm3\n6.02e19 cm3 \n6.02e13 m3\n6.02e5 km3\nroughly 602,000 km3
602189
u can go www.webmath.com, its pretty good. \nu can also ask on answers. \ni.e. 1cm = 10mm\n1m = 100cm or 1m = 1000mm\n1m = 3ft\n1ft = 12in \netc... hope it helps!
87064
A basic observable quantity for a star is its brightness. Because stars can have a very broad range of brightness, astronomers commonly introduce a logarithmic scale called a magnitude scale to classify the brightness.\nThe Magnitude Scale:\nThe magnitudes m1 and m2 for two stars are related to the corresponding brightnesses b1 and b2 through the equation:\nm1-m2=2.5(logb1-logb2)=2.5log(b1/b2)\nwhere "log" means the (base-10) logarithm of the corresponding number; that is, the power to which 10 must be raised to give the number. Because this relation is logarithmic, a very large range in brightnesses corresponds to a much smaller range of magnitudes; this is a major utility of the magnitude scale.\nThe preceding equation gives us a way to relate the magnitudes and brightnesses of two object, but there are several ways in which we could specify the brightness and this leads to several different magnitudes that astromers define. One important distinction is between whether we are talking about the apparent brightness of an object, or its "true" brightness. The former is a convolution of the true brightness and the effect of distance on the observed brightness, because the intensity of light from a source decreases as the square of the distance (the inverse square law). The apparent magnitude of an object is the "what you see is what you get" magnitude. It is determined using the apparent brightness as observed, with no consideration given to how distance is influencing the observation. Obviously the apparent magnitude is easy to determine because we only need measure the apparent brightness and convert it to a magnitude with no further thought given to the matter. However, the apparent magnitude is not so useful because it mixes up the intrinsic brightness of the star (which is related to its internal energy production) and the effect of distance (which has nothing to do with the intrinsic structure of the star).Clearly, a star that is very bright in our sky could be bright primarily because it is very close to us (the Sun, for example), or because it is rather distant but is intrinsically very bright (Betelgeuse, for example). It is the "true" brightness, with the distance dependence factored out, that is of most interest to us as astronomers. Therefore, it is useful to establish a convention whereby we can compare two stars on the same footing, without variations in brightness due to differing distances complicating the issue. \nAstronomers define the absolute magnitude to be the apparent magnitude that a star would have if it were (in our imagination) placed at a distance of 10 parsecs (which is 32.6 light years) from the Earth. I can do this if I know the true distance to the star because I can then use the inverse square law to determine how its apparent brightness would change if I moved it from its true position to a standard distance of 10 parsecs. There is nothing magic about the standard distance of 10 parsecs. We could as well use any other distance as a standard, but 10 parsecs is the distance astronomers have chosen for this standard. A common convention, and one that we will mostly follow, is to use a lower-case "m" to denote an apparent magnitude and an upper-case "M" to denote an absolute magnitude. \nNotice the very important point that I can determine the apparent magnitude m of a star simply by measuring how bright it appears to be, but to determine the absolute magnitude M the distance to the star must also be known. As we shall see, determining distances to stars is a quite non-trivial matter in the general case.You might think that introducing the apparent and absolute magnitudes would resolve ambiguities about what we mean when we refer to the brightness of a star, but there is a further complication. The brightness of an object (whether apparent or absolute) depends on the wavelength at which we observe it, as we saw clearly in the discussion of
1450
Go to the website below...\n\nhttp://hubblesite.org/
1031813
use the formula pi*r^2*h\nwhere pi=1.34\n r=radius (in inches)\n  h=height of cylinder (inches)
180255
The only way that I know to do this with a normal telescope is to compare the star with others nearby of known magnitude and try to decide if it's brighter or dimmer until you find the same.\n\nOtherwise you'd need to measure the amount of light that comes from it, and I think you need computers to do that.\n\nThe magnitude scale is exponential, so deciding a magnitude ain't that simple. (ie a star of magnitude +2 is ten times brighter than a star of magnitude +3)
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Size of Star depends on how it was formed originally. I don't think it could be said precisely. U can take the size of our sun as a measure. Radies=6400kms
72281
go to \nhttp://www.pbs.org/wgbh/nova/elegant/dimensions.html\nand/or watch The Elegant Universe (NOVA)
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This isn't in the form of a graph, but it might help -->http://www.cosmobrain.com/cosmobrain/res/nearstar.html
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a galaxy is a group of stars, consisting of a few hundred million or more, depending on their size.\n\nour galaxy is called the milky way, and the nearest galaxy is the andromeda galaxy