Compared to when the cosmic microwave background was first released, the radiation of the cosmic microwave background today is fainter and has most of its photons at longer wavelengths
<h3>What about Cosmic microwave background?</h3>
The cosmic microwave background is electromagnetic radiation that was produced during the early universe and is frequently referred to as "relic radiation" in Big Bang cosmology.
All of space is filled with the feeble cosmic background radiation, or CMB.
It is the oldest electromagnetic radiation in the cosmos, dating to the era of recombination when the first atoms were created, making it a significant source of information about the early universe.
The backdrop (the area between stars and galaxies) is completely dark when using a conventional optical telescope.
A sufficiently sensitive radio telescope, however, detects a very faint background glow that is essentially uniform and unrelated to any stars, galaxies, or other objects.
The microwave region of the radio is where this glow is greatest.
