Scientists have used the big bang theory to make numerous predictions about the universe. One of their predictions is that about 75% of the visible matter in the universe should be hydrogen and about 25% should be helium.
How could a scientist test this prediction?
A.
collect molecular samples from stars and galaxies to determine their composition
B.
compare the number of galaxies with blueshifted spectra to those with redshifted spectra
C.
measure the amount of cosmic microwave background radiation in the universe
D.
analyze the spectra of electromagnetic radiation from stars and galaxies
D. analyze the spectra of electromagnetic radiation from stars and galaxies
By analyzing the spectra of electromagnetic radiation from stars and galaxies, scientists can determine the composition of elements present in these celestial bodies. If approximately 75% of the visible matter in the universe is hydrogen and 25% is helium, scientists should be able to observe this composition in the spectra they analyze. If their observations match the predicted percentages, it would provide evidence in support of the big bang theory.