Vocabulary # 11

Vocabulary # 11

Galaxies and Beyond

Galaxy : A large group of stars held together by gravity . 



I think galaxy looks like a Nebula .

Milky way : Our home galaxy .



Milky way is our home galaxy .

Spectrum : A band of colors made when white ligth is broken up .

                                                     

All the colors of the spectrum are beautiful .

Expansion redshift : The shift of a spectrum of a galaxy toward longer ( redder ) wavelengths due to the expansion of space.



 I really dont understand what is expanasion redshift.

Big Bang : The beginnig of the universe, when the density of the universe was very high .



I dont believe in the theory of the big bang .

Background radiation : Electromagnetic radiation left over from the big bang .

                                            

I make 29 sentences about Background radiation .

Quasar : An extremely brigth , distan , high -nergy source .



                                            

Quasar is the bigest source of energy in the space .