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What do the lines in the spectra of most galaxies shifted toward the red end of the spectrum show?
Wiki User
∙ 10y ago
The strongest consensus (nearunanimous of the astronomical community is that the redshifts of distant galaxies indicate that all distant galaxies arerecedingfrom us. This recession is currently the only known mechanism for redshifting light. Take this inference, that all galaxies arereceding and you are led to the idea that the universe is expanding, a phenomena described by Hubble's Law. This is a central tenet to the Big Bang Theory.
I will include the counterpoint originally described below, but I will point out that the papers cited are very old, and a huge number of corroborating observations and predictions of the big bang haveoccurredsince then.
The conclusion that the Universe is expanding is a wrong conclusion. Alan Sandage talks about Hubble's position at the related link below.
To the very end of his writings he maintained this position, favouring (or at the very least keeping open) the model where no true expansion exists, and therefore that the redshift "represents a hitherto unrecognized principle of nature". This viewpoint is emphasized (a) in The Realm of the Nebulae, (b) in his reply (Hubble 1937a) to the criticisms of the 1936 papers by Eddington and by McVittie, and (c) in his 1937 Rhodes Lectures published as The Observational Approach to Cosmology (Hubble 1937b). It also persists in his last published scientific paper which is an account of his Darwin Lecture (Hubble 1953).
Wiki User
∙ 11y ago
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How do astronomers determine the speed at which a galaxy is moving?
By examining its spectrum, and identifying absorption lines in it. Lines are shifted toward shorter wavelength if the object is moving towards us. They're shifted toward longer wavelength if the object is moving away from us.
Why is the west limb of the sun red-shifted and the east limb blue-shifted?
Because the sun is rotating. So its west limb is moving away from us and its east limb is moving toward us ... the exact conditions required in order to shift the emission spectrum.
What happen to the spectrum of a star moving toward the earth away from the earth?
If a star is moving towards Earth. The light is seen as 'blue shifted'. As we look at our sun, on the colour spectrum, black lines appear. When looking at distant stars, we can tell if they are moving away from us (Red shift) or getting closer to us (Blue shift). This is because the black lines shift to the red or blue end of the spectrum depending on which direction the star is travelling.
What is indicated by a shift of galaxy spectral line toward the red part of its spectrum?
In simplest terms, the shift of galactic spectral lines towards the red end of the spectrum would indicate simply that the galaxy in question is receding from the observer. This is an example of the Doppler effect, where the frequency is lowered (wavelengths become longer, and in this case energy of the photons is decreased) by the relative motion of the observer. The redshifting of galaxies in all directions became the primary evidence of an expanding universe (cosmological redshift). Because the expansion of the universe is fairly uniform in all directions, those galaxies that are most distant are receding the fastest and thus evidence the greatest amount of redshift. By contrast, if a characteristic spectral line of a galaxy or other object shifted towards the blue end of the spectrum (shorter wavelengths), it would be traveling towards the observer.
A star moving away from the earth will have a spectrum containing?
When the source of light is moving away from us, any reconizable features againstthe background of its continuous spectrum ... such as discrete absorption or emissionlines ... are shifted toward longer wavelengths.In order to recognize that somethng is going on, we must be able to identify theorigin of the features, and know what wavelength they belong at. If we just seesome lines on top of some colors, none of that tells us anything.
In 1912 an astronomer at Arizona's Lowell Observatory noticed that the lines in the spectra of most galaxies shifted toward the red end of the spectrum Another American astronomer Edwin Hubble lat?
Galaxies are moving away from each other in a constantly expanding universe
What is it called when galaxies are moving toward each other?
There isn't a particular name, however, when they are moving towards us, their spectrum is shifted to the blue region. So they are referred to as blue shifted galaxies but that is only relative to ourselves. See related link for more information.
If light experiences the Doppler effect what will happen to its color?
If light is subject to the Doppler effect, it will change color. The light changes color toward the lower (red) end of the spectrum or the upper (blue) end of the spectrum. Which way the color shifts depends on whether the distance between the source and the observer is increasing or decreasing. Should we find the distance is increasing, the light will be shifted toward the red end of the spectrum. This is called redshift (one word), and astronomers know this well because most all galaxies are speeding away from the Milky Way and have their light shifted toward the red end of the spectrum. If the distance between a source and observer is decreasing, the color of the light will be shifted toward the blue end of the spectrum. In either case, the amount the color is shifted will be determined by the rate the distance between the source and observer is changing. If a galaxy is moving away from the Milky Way, we'll see a shift toward red, and if another galaxy is moving away faster, will see a greater shift in the color of the light from it.
Galaxies that show redshift in color must be red in color?
No. You can figure out exactly what elements are in stars and galaxies by examining the color spectrum of the light detected; the frequencies of the bright and dark lines in the spectrum tell you what's what. But there's a problem. For distant galaxies, the light spectrum is wrong. The frequency lines of the spectrum are all too low. One possible explanation of the incorrect spectrum is that those stars and galaxies are MOVING AWAY from us, and that the spectrum is shifted toward the red end of the color spectrum because of the Doppler effect. So scientists believe that the "red-shift" on the color spectrum of stars and galaxies indicate that they are moving away. Not all galaxies show a red-shift; the Andromeda Galaxy, M31, shows a pronounced BLUE-shift, indicating that it is heading TOWARD us. In fact, scientists believe that the Milky Way and Andromeda will probably collide in about 3 billion years.
A star whose spectral lines are shifted toward the red end of the spectrum?
In simplest terms, the shift of galactic spectral lines towards the red end of the spectrum would indicate simply that the galaxy in question is receding from the observer. This is an example of the Doppler effect, where the frequency is lowered (wavelengths become longer, and in this case energy of the photons is decreased) by the relative motion of the observer. The redshifting of galaxies in all directions became the primary evidence of an expanding universe (cosmological redshift). Because the expansion of the universe is fairly uniform in all directions, those galaxies that are most distant are receding the fastest and thus evidence the greatest amount of redshift. By contrast, if a characteristic spectral line of a galaxy or other object shifted towards the blue end of the spectrum (shorter wavelengths), it would be traveling towards the observer.
What did Hubble conclude when he noted that light emitted from stars is shifting toward the red of the electromagnetic spectrum?
He noted that light emitted from stars is shifted further toward the red of the electromagnetic spectrum . From this he concluded that the universe was expanding.
How do astronomers determine the speed at which a galaxy is moving?
By examining its spectrum, and identifying absorption lines in it. Lines are shifted toward shorter wavelength if the object is moving towards us. They're shifted toward longer wavelength if the object is moving away from us.
If a star is moving toward Earth it is?
blue shifted
Why is the west limb of the sun red-shifted and the east limb blue-shifted?
Because the sun is rotating. So its west limb is moving away from us and its east limb is moving toward us ... the exact conditions required in order to shift the emission spectrum.
What does the blue shift mean in regard to stars and galaxies?
Light is a spectrum. On one end it is red and the other blue. We see light in this spectrum as waves and if it is blue, the object is coming toward us. If the waves are red than it is moving away. The frequency of these waves tell us how fast and object is moving toward or away from us.
How does a red shift indicate that the universe is expanding?
nice question! actually when a wave approaches an observer the wave length of the wave decrease and as it move far from us its wavelength increase. it is quiet difficult to understand so use your imagination. as the wavelenght increase the spectrum will be shifted toward red spectrum and thus called red shift. when Edward Hubble studies spectrum of different star he noticed that because of some color spectrum were missing, other spectrum got shifted to ward red. it it moved toward red then that mean that wavelength was increasing and if wavelength increases then that means light moves away from us and thus he concluded that each and every star and galaxy was moving away from each other
If a star is moving toward earth is it?
blue shifted
