1. The problem statement, all variables and given/known data The temperature of Sun's surface is 5700K, and the temperature of Earth's surface is 290K. What's the variation of entropy when 1000J of energy is transferred by radiation from the Sun to the Earth? 2. Relevant equations 3. The attempt at a solution Since the temperature of the Earth is approximately the same by receiving 1000J of energy, I multiplied 1/290 by 1000J, but the answer gave me 3.44 J/K, while the correct answer is 3.27 J/K.