'Red shift' is a key concept for astronomers. The term can be understood literally - the wavelength of the light is stretched, so the light is seen as 'shifted' towards the red part of the spectrum.
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I believe that the other person who answers u is right
Answer:
1st) Sagittarius Dwarf Elliptical Galaxy
2nd) Virgo Stellar Stream
3rd) Canis Major Dwarf
4th) Milky Way Galaxy
Explanation:
