CMBR COBE and Penzias/Wilson


#1

IMG_2037
The above is from COBE. Frequency is in 1/cm so 2 on the x-axis is ~60 GHz and 16 is ~480 GHz if I’m not making a blunder. Why didn’t COBE measure at 4.08 GHz like Penzias and Wilson in 1965?