Arno Penzia and Robert Woodrow Wilson theorized that if the Big Bang theory was correct, the universe would be filled with background radiation left over from this event. The evidence of this energy, called cosmic microwave background (CMB) radiation, is the oldest light we can detect and is estimated to be around 13.7 billion years old. It is evidence of the universe's beginning, when it was a hot space filled with radiation and energized particles instead of the cold dark space containing stars and planets that we see today.
Which of the following statements support the discovery of CMB?
Group of answer choices
Stars and planets were present when the universe first formed.
The universe was always the same temperature and density.
Hydrogen was the first element produced after the Big Bang.