Twenty Three miles may not seem very far, but in 1973, this was a great distance to travel on the moon. This infographic shares distances traveled by various crafts on the moon and on mars, from farthest to shortest. Currently, curiosity is traveling on the surface of Mars at the breakneck speed of nearly half a mile thus far. It is collecting data and specimen as it travels slowly over this uncharted territory. But there are more factors involved than simply speed and distance.
Gather information on each mission and find out what the reason for the mission was. When Europeans first landed on the coast of America, they did not travel to the other side of the coast, they wanted to gather information and explore little by little, they did not know what could be on the other side of a forest. Were the missions only to gather information on terrain, to try to land on the surface in the first place, or to map out the planet further? In addition, how many expeditions had occurred previous to each mission. An initial mission will have more basic goals than later missions.
Compile a list of missions, and their goals and duration, as well as potential and actual problems during the mission. Compare the missions beyond the distance traveled on the planet, and try to figure out which mission was the most successful.