1. The problem statement, all variables and given/known data What should be the average temperature on Pluto, at its 5.9 * 10^12 distance from the Sun? Treat Pluto as a blackbody. Assume that the effective solar intensity is 68 %. 2. Relevant equations Power of radiation = (sigma)eAT^4 3. The attempt at a solution From the text, the power of the sun is 3.9 * 10^26 Watts. Since intensity if 68%, I multiplied that by .68 to get the new power. I then divided that value by e (given), the area (4(pi)r^2 where r is 5.9*10^12, and sigma (given, 5.7*10^-8). I then took the fourth root of that, and got 57 K. This is not the correct answer. For reference, the temperature with 100% solar intensity is 40.7 K. I could not replicate that either. Any help is appreciated, thanks!