- #1
Viper
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Can anyone explain to me the red shift
Redshift Basics: What is the Redshift Phenomenon?
- Thread starter Viper
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- Basics Phenomenon Redshift
In summary, The red shift is caused by the doppler effect, which occurs when a source emitting waves moves towards or away from the observer. This causes the waves to arrive closer together (blue end of the spectrum) or become more stretched out (red end of the spectrum). In astronomy, there are three types of redshift: doppler, gravitational, and cosmological. The red shift is not visible in everyday life, but can be observed through measuring the wavelength of light from distant galaxies. Super novae, which are not very predictable, can sometimes be seen in the sky for about a week if they are bright enough.
- #2
Jack
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Red shift occurs as a result of the doppler effect. When a source that emits waves moves towards you the waves emitted by the object arrive earlier than they would if the object was not moving and therefore waves arrive closer together (light moves towards the blue end of the spectrum). If the source is moving away from you the waves get more stretched out (the light moves towards the red end of the spectrum).
- #3
russ_watters
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You know how the pitch of a train horn changes as it passes you? Thats the doppler effect. Same effect for light just that higher frequencies are toward blue and lower ones toward red.
- #4
Phobos
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In astronomy, there are 3 kinds of redshift...
(1) Doppler (see above)
(2) Gravitational (from light climbing out of a strong gravity field)
(3) Cosmological (expanding space stretching light waves)
(1) Doppler (see above)
(2) Gravitational (from light climbing out of a strong gravity field)
(3) Cosmological (expanding space stretching light waves)
- #5
Viper
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Is the red shift visible then and how do I go about seing it?
- #6
Mulder
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I don't think you can go about observing a shift in light in everyday life. It's observed from stars in distant galaxies moving away from us at very high velocities. you would probably need a relative velocity of around 0.10c so that the Doppler factor for EM waves, sqrt((c+u)/(c-u)) gives a noticeable shift in wavelength.
So unless you've got the tools to measure the wavelength of light received from far-away stars, and compare with what the true wavelength should be, you might have to settle for sound
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So unless you've got the tools to measure the wavelength of light received from far-away stars, and compare with what the true wavelength should be, you might have to settle for sound
.- #7
Viper
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My other question is that I've heard a lot about stars going super nova, do you know when I can view these?
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- #8
russ_watters
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It doesn't happen very often and its not all that predictable - so if there is a good one you might be able to see it after reading about it in the newspaper. They're generally visible for a week or so if they get bright enough.