In this article, we will be providing a brief summary about the remaining Apollo Missions (13, 14, 15, 16, and 17).

Apollo 13 (Apr 11–17, 1970): Apollo 13 has been called a “successful failure,” because the crew never landed on the Moon, but they made it home safely after an explosion crippled their ship. A switch and insulation, which should have been modified during an upgrade to one oxygen tank, were damaged during a test of that tank during construction. When the associated heater was turned on during the flight, the tank exploded, depleting almost all of the power from the command module and forcing the crew to use the lunar module as a lifeboat. Jim Lovell, Fred Haise, and Jack Swigert came home safely thanks to the mission control team’s improvised procedures and their own ability to implement them.

Apollo 14 (Jan 31 – Feb 9, 1971): Notable for the return of America’s first astronaut, Alan Shepard, to space, Apollo 14 also was probably the smoothest lunar landing to that point. The crew spent more than nine hours outside the lunar module and set up a number of experiments. Shepard set a new distance record by walking more than 9,000 feet on the lunar surface, pulling a hand cart to carry their tools and samples.

Apollo 15 (Jul 26 – Aug 7, 1971): For the first time, humans drove a car on the Moon. The first of the Apollo “J” missions – designed for longer stays on the Moon – mission carried a lunar rover, which Commander David Scott and Lunar Module Pilot James Irwin used while they were on the surface for more than 18 hours. They traveled more than 17 miles in the rover, setting up experiments and collecting 170 pounds of samples. Before leaving the lunar surface, Scott conducted an experiment to test Galileo’s theory that objects in a vacuum, without air resistance, would fall at the same rate. He dropped a geological hammer and a feather, which hit the ground at the same time, proving Galileo right.

Apollo 16 (Apr 16–27, 1972): Apollo 16 also took advantage of having a lunar rover, as Commander John Young and Lunar Module Pilot Charles Duke drove more than 16 miles over three moonwalks, collecting 209 pounds of samples. Problems forced mission controllers to cut the flight short by a day, but the return trip included a spacewalk by Command Module Pilot Ken Mattingly to retrieve film from a camera in the service module.

Apollo 17 (Dec 7–19, 1972): The last Apollo mission featured the most extensive lunar exploration of the program, with three moonwalks that each lasted more than seven hours while the crew stayed on the Moon for more than three days. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt – the first scientist-astronaut to reach the Moon – collected 243 pounds of material. These samples, and those from the previous missions, continue to reveal more about the Moon as new tools and techniques are developed and applied.
Project Apollo cost $25.4 billion (or approximately $153 billion in 2018 dollars when adjusted for inflation via the GDP deflator index). After the first Moon landing, public and political interest waned, including that of President Nixon, who wanted to rein in federal spending.
The Apollo program resulted in American astronauts’ making a total of 11 spaceflights and walking on the moon. A total of 12 astronauts walked on the moon. The astronauts conducted scientific research there. They studied the lunar surface. They collected moon rocks to bring back to Earth.
References:
https://airandspace.si.edu/explore-and-learn/topics/apollo/apollo-program/
https://www.nasa.gov/mission_pages/apollo/missions/index.html
https://www.nasa.gov/specials/apollo50th/missions.html
https://en.wikipedia.org/wiki/Apollo_program