The key to finding quasars' distances was
A) globular clusters in the halo of M87 in Virgo.
B) planetary nebula in M51.
C) a Type I supernova in the spiral arm of 3C87.
D) the luminosity of 3C52 from the Doppler shift and the Fisher- Tully relation.
E) the huge redshifts of the hydrogen lines in 3C273.

Question

Quizplus · Accepted Answer

The key to finding quasars' distances was the discovery of their huge redshifts, particularly in the hydrogen lines, which indicated that they were moving away from Earth at a significant fraction of the speed of light. This discovery, notably in quasar 3C273, provided a method to estimate their distances through the Hubble Law, which relates the redshift of a galaxy to its distance from Earth.

The Key to Finding Quasars' Distances Was