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 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.

[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.

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.