Which of the following is not an observed characteristic of the cosmic microwave background?
A)It has a perfect thermal radiation spectrum.
B)Its temperature is the same everywhere,except for small variations at the level of 1 part in 100,000.
C)Its temperature is a little less than 3 Kelvin (3 degrees above absolute zero).
D)It contains prominent spectral lines of hydrogen,the primary chemical ingredient of the universe.

Question

Quizplus · Accepted Answer

The cosmic microwave background does not contain prominent spectral lines of hydrogen, as it is a thermal radiation spectrum that is characteristic of a blackbody radiation.

Which of the Following Is Not an Observed Characteristic of the Cosmic