it does not interact with baryonic matter

Question

Question 8
Which statement is INCORRECT about Cosmic Microwave Background radiation?(2 points)
Responses

its temperature is uniform.
its temperature is uniform.

It appears uniformly across the universe.
It appears uniformly across the universe.

it appeared only a few years ago
it appeared only a few years ago

it consists of electromagnetic radiation that is a remnant of the Big Bang.

Answer 1

The INCORRECT statement about Cosmic Microwave Background radiation is:

it appeared only a few years ago.

The Cosmic Microwave Background (CMB) radiation is actually the remnant radiation from the Big Bang, and it dates back to approximately 380,000 years after the event, when the universe cooled enough for protons and electrons to combine to form neutral hydrogen atoms. Hence, saying it appeared only a few years ago is incorrect.