GK
BIG BANG THEORY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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toward Earth
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away from Earth
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not moving
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None of the above
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Detailed explanation-1: -When an object is moving away from us, the light from the object is known as redshift, and when an object is moving towards us, the light from the object is known as blueshift. Astronomers use redshift and blueshift to deduce how far an object is away from Earth, the concept is key to charting the universe’s expansion.
Detailed explanation-2: -If a star is moving toward us, its light waves get scrunched up to shorter, or bluer, wavelengths, producing a blueshift. If a star is moving away, its light waves get stretched out to longer, redder, wavelengths, producing a redshift.
Detailed explanation-3: -While the star is moving away from us, the light is redshifted: All of the wavelengths look stretched out and the absorption lines appear at longer (redder) wavelengths (bottom spectrum).