1. The problem statement, all variables and given/known data Calculate the spectral radiant exitance for a 10um black body at the following temperatures: -12.0°C, 0°C, 12°C, 1600 K, and 2500 K Known: wavelength = 10um temperature = see above 2. Relevant equations Planck's equation I think 3. The attempt at a solution No idea. I can't figure out the equation (I am a major noob at this). The given equation is: Mλ = C1 / (λ5 [e(C2/λT) - 1) λ = wavelength in micrometres T = temperature in Kelvin C1 and C2 are supposed to be Planck's constants. What does the "e" mean?