Q19.
Which of the following is/are cited by the scientists as evidence/evidences for the continued expansion of universe? 1. Detection of microwaves in space. 2. Observation of redshift phenomenon in space. 3. Movement of asteroids in space. 4. Occurrence of supernova explosion in space. Select the correct answer using the codes given below:
Answer
A
Explanation
Both detection of microwaves (cosmic microwave background radiation — leftover from the Big Bang) and observation of redshift phenomenon (galaxies moving away from us) are cited as evidence for the continued expansion of the universe. For example, other scientists found evidence for it when they analyzed the microwave radiation left over from the big bang that still bathes the universe. Redshift (point 2) is well-known evidence which eliminates options C and D. Movement of asteroids and supernova explosions are NOT evidence for universal expansion.