Question

Using P = eσAT⁴, one estimate speculates that the temperature on Mars is 226 K. How does this compare to the actual average temperature of Mars?

Answer 1

in this case , it is used Stefan-boltzmann law to calculate the temperature of the mars by noting the flux of energy coming out from the surface of the mars. this law is valid for a perfect black body. in actual case mars is not a perfect black body. it would not absorb all the radiation coming into it or reflected. instead some of its abosrbs and some of it reradiated . a few percentage is reflected back to the space itself. therefore without accounding the radiation which is re-radiated back to the atmosphere of the mars , the estimated temperature is not the actual one . the actual temperature would have greater value than the observed using Stefan-boltzmann law.