the universe

Question 1

the universe is…

Answer 1

expanding

Question 2

why can we tell the universe is expanding?

Answer 2

redshift- the wavelengths from different galaxies light rays is getting bigger
galaxies further away have greater redshift (redshift is only on moving object) so it is travelling faster away

Question 3

universe expanding theory

Answer 3

the big bang- exploded from one small point

can use expansion rate to estimate age of the universe- 14 billion years old

Question 4

cosmetic microwave background radiation

Answer 4

scientists have detected low frequency electromagnetic radiation from all parts of the universe
largely in microwaves

Question 5

big band theory and CMBR

Answer 5

just after the big bang the universe was very hot- everything emitted high frequency radiation.
as the universe expanded it cooled- dropping the frequency to microwave

Question 6

why not big bang theory

Answer 6

elements of the universe it still can’t explain- universe expansion should be slowing down due to theory but is actually speeding up
no theory for what caused the explosion or conditions before explosion
will be adapted not dropped altogether