Wavelength of the Cosmic Microwave Background?

[Yora]

It must have one, but I am unable to find out how long it is. Or even its frequency in hz.

[georgie_leech]

My Finals are done so I'm in a strict "No calculations" phase, but you could plug the frequencies on this chart (https://en.wikipedia.org/wiki/Cosmic_microwave_background#/media/File:Cmbr.svg) into our good friend λf=c.

[Excession]

From Wikipedia:

"The CMB has a thermal black body spectrum at a temperature of 2.72548±0.00057 K. The spectral radiance dEν/dν peaks at 160.23 GHz, in the microwave range of frequencies."

It's a black body curve, not a single frequency, but the peak is at 160 GHz.

[gomipile]

So, 1.871 millimeters.

[Yora]

That's still really short, but it is a distance we can actually see.

[Lvl 2 Expert]

Technically yes, although in terms of radiomagnetic waves I´m not sure if "the wavelength is something I could see if it was a physical object" is the most useful criterium for how relatable something is. :smallwink:

[gomipile]

Technically yes, although in terms of radiomagnetic waves I´m not sure if "the wavelength is something I could see if it was a physical object" is the most useful criterium for how relatable something is. :smallwink:

Well, it is when you're building antennas by hand, or building reflectors or Faraday cages for that wavelength. That's all I've got off the top of my head, though.