What is the Q of a Blackbody? A small contribution to Gustav Robert Kirchhoff's bicentennial

The blackbody spectrum “half-power points” are used to assign effective Q “quality factor” values that are found to be less than unity whether frequency or wavelength scaling is used. A comparison with values for coherent oscillators is made. This exercise blends two of Kirchhoff’s interests, and is instructive in its own right, as it bridges the often mutually exclusive engineering and scientific disciplines.