Given the z redshift of 1089, and the temperature difference between then and now of about 1089, I tried scaling the ev, freq. and wavelength by 1089....
Is that right?
I get a freq. of about 240 Terahertz, 1.25 micron wavelength and almost exactly 1 ev of photon energy.....
Does that correspond to a blackbody temperature of just under 3000 K?