The logo for The COSETI Observatory is presently under design. The expression above "COSETI" is well-know to scientists and engineers. It indicates that the energy in a quanta of light, otherwise known as a photon, is much greater that thermal kT energy. Thus, the reference to "hot" optical photons in comparison to "warm, fuzzy" microwave photons. This was a favorite comment of the late Barney Oliver in reference to his very strong preference for the microwave approach to SETI.
The parameters in this classic formula have the following values:
h = Planck's constant (6.63 x 10-34 J.s)
f = frequency (4.57 x 1014 Hz) for a visible wavelength of 656 nm
k = Boltzmann's constant (1.38 x 10-23 J/K)
T = temperature (300 K)
hf = 3.03 x 10-19 Joules
kT = 4.14 x 10-21 Joules
Proving that at visible optical frequencies and room temperatures, hf is greater than kT by two orders of magnitude.