The majority of the redshift that we measure from the most distant galaxies is due to
A) excess hydrogen emission.
B) most of these galaxies being old, elliptical-type galaxies.
C) the expansion of the universe "stretching" the wavelengths of photons.
D) the cosmic microwave background.
E) the actual velocity of that galaxy.

Question

Quizplus · Accepted Answer

The redshift observed in distant galaxies is primarily due to the expansion of the universe, which stretches the wavelengths of photons, causing them to shift towards the red end of the spectrum. This is known as cosmological redshift.

The Majority of the Redshift That We Measure from the Most