From https://www.cbo.gov/publication/18196 https://www.cbo.gov/publication/18196, the link above: "The payload of 140 metric tons is derived from weight data p

From https://www.cbo.gov/publication/18196 https://www.cbo.gov/publication/18196, the link above: "The payload of 140 metric tons is derived from weight data pro-vided in Richard W. Orloff, Apollo by the Numbers: A Statistical Reference, NASA SP-2000-4029 (National Aeronautics and Space Administration, updated September 27, 2005), available at http://history.nasa.gov/SP-4029/SP-4029.htm http://history.nasa.gov/SP-4029/SP-4029.htm. In that reference, 140 mt is the weight of the Apollo 17 command-and-service modules, the lunar module, the spacecraft/lunar module adapter, the instrument unit, and the S-IVB stage (the third stage of the Saturn V), including the fuel remaining in that stage needed to propel the Apollo command-and-service modules and lunar module from low earth orbit to the moon." So this number includes the S-IVB stage and unspent fuel. Which ought to raise the question of the definition of the payload - we don't usually consider launcher's parts among payload mass. > Mass of the payload to LEO is just how much mass is brought to LEO. No, it's usually not that simple - Space Shuttle here doesn't include Orbiter's mass (I think it's a mistake), Sputnik payload didn't include R-7 second stage (I think it's right), Energia doesn't have 0 LEO payload even though it releases the payload below LEO (I think this definition is also more meaningful).