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Like sound, light waves moving away from the observer are stretched making the wavelength longer and when light comes toward us it appears to become compressed.
Since the bottom end of the spectrum is red and the top blue, an object which radiates light appears to be red shifted when it moves away from us as the light wave is stretched. It has been observed that all stars are red shifted, therefore the conclusion is that all stars are moving away from us in space.
This effect is called Doppler shift and is the reason a car engines note sounds higher as the car approaches and lower as it moves away from the listener.
What else can I help you with?
When a star or galaxy moves quickly away it is called what?
We can measure fairly accurately the radial speed of a star or galaxy by measuring the Doppler shift of the emitted light from the star. Stars emit specific frequencies of light, and we can measure the frequencies to determine what elements are contained within the star. But since we know exactly what the frequencies are, we can measure the precise frequencies that we measure from the star. A star moving toward us will have its light "blue-shifted", or compressed a tiny bit in frequency. The amount of the compression tells us the radial velocity. A star whose light is red-shifted is moving away from us. Radial velocity is the part of the velocity that is directly toward or away from us; Doppler shifts don't tell us anything about a star's side-to-side motion. One of the astonishing discoveries of Edwin Hubble is that most galaxies are moving away from us, and the farther away they are, the faster they seem to be receding. Some nearby galaxies are moving closer, but the more distant the galaxy, the faster it is moving moving away. He determined this by the "red shift" of the light from distant galaxies.
What is the Andromeda Galaxy's red shift?
The Andromeda Galaxy red shift is -301 km/s Which actually means it is blue shifted and is heading towards us at about 100 to 140 kilometres per second
What galaxy did hubble discover?
-- Once you get past our "local group", every galaxy is moving away from us. -- The farther any galaxy is from us, the faster it's moving away from us.
How do you use spectral lines to determine if a galaxy is moving towards earth or away from earth?
The spectral lines move towards one direction, or towards the other direction, depending on the relative speed.
Spectrographs help astronomers determine a star's what?
The star's chemical composition; the star's rotation; pulsations of the star; planets or other invisible objects moving around the star; how quickly the star is moving towards us or away from us.
How does light from distant galaxy . galaxy out side of 32000000 light years support the big bang theory?
The light from distant galaxies is redshifted. The only reasonable explanation for that is that the galaxies are moving away from us.
How does imaging determine how fast a distant galaxy is moving away from Earth.?
The star's spectrum is analyzed; certain lines in the spectrum, which have a fixed position, will change their position when the object moves away from us or towards us.
What is the pattern between how far away galaxies are and how quickly they are moving?
The farther a galaxy, the faster it moves away from us.
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.
How is the cosmological motion of a distant galaxy fundamentally different from the motion of an object speeding through space?
The object - planet, meteoroid, comet, spaceship - is traveling THROUGH space; the galaxy is moving away WITH space. That is, the space itself is expanding.
When a star or galaxy moves quickly away it is called what?
We can measure fairly accurately the radial speed of a star or galaxy by measuring the Doppler shift of the emitted light from the star. Stars emit specific frequencies of light, and we can measure the frequencies to determine what elements are contained within the star. But since we know exactly what the frequencies are, we can measure the precise frequencies that we measure from the star. A star moving toward us will have its light "blue-shifted", or compressed a tiny bit in frequency. The amount of the compression tells us the radial velocity. A star whose light is red-shifted is moving away from us. Radial velocity is the part of the velocity that is directly toward or away from us; Doppler shifts don't tell us anything about a star's side-to-side motion. One of the astonishing discoveries of Edwin Hubble is that most galaxies are moving away from us, and the farther away they are, the faster they seem to be receding. Some nearby galaxies are moving closer, but the more distant the galaxy, the faster it is moving moving away. He determined this by the "red shift" of the light from distant galaxies.
What is the Andromeda Galaxy's red shift?
The Andromeda Galaxy red shift is -301 km/s Which actually means it is blue shifted and is heading towards us at about 100 to 140 kilometres per second
How can the Doppler effect determine if things are moving towards a distant galaxy or away from one?
Light had properties of frequency that related to colour. It is apparently contract in the direction moving toward the observer (higher frequency-short wavelength) and apparently elongated in the direction moving away from observer (lower frequency-high wavelength). What moving toward us is tend to be look more blue than usual (blue shift) and what away from us is redder than usual (red shift).
What if no distant galaxies showed any redshift or blueshift?
It would mean that the universe was radially static. That is, no galaxy was moving towards or away from the earth. This could happen if everything in the whole universe were moving in the same direction at the same [linear or rotational] velocity.
How do red shifts were used by cosmologists to determine that the universe is expanding?
A Galaxy's red-shift can be used to determine how fast it is travelling away from you. The opposite is "blue-shift" which is what happens when the Galaxy is travelling towards you.The first astronomers, such as Edwin Hubble, to analyse the light coming from distant galaxies discovered that almost all of them were red-shifted, indicating that they were almost all heading away from us. This was the first indication that the universe was expanding.
Does the colour of a galaxy reflect its distance away from the earth?
No, however, we can determine whether a galaxy is moving towards or away from us, by looking at the shift in its spectrographic analysis. There are "red shifts" and "blue shifts" in spectrographic results. "Blue shifts" indicate that a galaxy is moving towards us, because the wavelength of the light emitted by the galaxy is compressed, causing it to shift to the blue end of the colour spectrum. "Red shifts" indicate that a galaxy is moving away from us, because the wavelength of the light emitted by the galaxy is being stretched towards the red end of the colour spectrum.
How fast is the milky way galaxy moving away from us?
We are part of the milky way galaxy, so we are moving with it.
