The Cosmic InfraRed Background (CIRB) is the radiation from stars in many faint galaxies. ... The near-infrared (wavelengths near 2-3 microns) and optical (wavelengths near 500 nm) part of this extragalactic background light is just starlight redshifted into the infrared. But some starlight is absorbed by dust and re-emitted in the far-infrared (wavelengths near 100 microns). ... The CMB is by far the largest of these radiation fields, with a total intensity of 996 nW/m 2 /sr. ... Part 2 | ...