The Apollo missions conducted between 1967 and 1972 marked the beginning of our expansion beyond Earth. The words "That's one small step for a man. One giant leap for mankind." uttered by Neil Armstrong as he stepped on the Lunar surface were just a part of those arduous expeditions that tested our determination as a race. Each Apollo mission was framed by a clear goal: to expand our reservoir of knowledge about that bright rock that orbits around us and which has such a profound cultural and physical effect on our planet. Recently NASA released a series of 8,400 photographs that reveal never before seen moments from the various Apollo missions to and around the Moon that shaped our modern understanding of space travel. Here you will find a selection of the best images that outline these crucial steps in our shared human history. NASA Unfortunately, the first Apollo mission was not as promising as its successors. On Jan. 27, 1967, tragedy struck when Astronauts Virgil Grissom, Edward White and Roger Chaffee lost their lives when a fire broke out in the command module, or CM. The investigation on what caused the fire lead to the Saturn IB launch vehicle being suspended for almost a year until lunar module, instead of the originally planned command module, was launched into orbit. NASA We did not have another Apollo lunar mission until October 11, 1968. Apollo 7 was an engineering test flight to demonstrate the command and service module (CSM) and crew performance as preparations for future space missions. NASA This mission became the first time the moon's far side was seen by human eyes. The crew of astronauts Frank Borman, William A. Andres and James A. Lovell Jr. spent a total of 20 hours orbiting the moon. NASA Apollo 9 tested the rendezvous and docking capabilities of the command and service module (CSM) and lunar module (LM). The tests conducted were in preparation to the planned lunar orbit of Apollo 10. NASA After preparing the rendezvous and docking mechanisms, Apollo 10 became about actually getting the crew to the surface of the moon, minus the landing. This was the first flight of a complete Apollo crew to operate around the moon. A separated lunar module (LM) descent into lunar orbit approximately nine miles off the moon's surface before ascending and docking with the command and service module (CSM). NASA On July 20, 1969 Commander Neil Armstrong along with pilot Michael Collins and Edwin "Buzz" Aldrin became the first humans to set foot on the surface of the Moon. NASA After the worldwide event of Apollo 11, 12 had a more specific task in mind. This time around a new crew was to deploy the Apollo Lunar Surface Experiments Package, or ALSEP. This package would be left on the Moon's surface to gather data through long periods of time. Along with this objective the mission also included the evaluation of the abilities for humans to work in the lunar environment for prolonged periods of time. NASA Another famous phrase from space travel was born during the Apollo 13 mission. This was another scheduled landing to the moon to gather more data after landing in the Fra Mauro area of the Moon. Unfortunately, an explosion on board forced the crew to circle the moon without landing. NASA Following the minor setback from Apollo 13, 14 saw the successful exploration of the Fra Mauro region of the Moon. 94 punds of rocks and soil were collected and brought back to Earth for further analysis. NASA On July 31, Aug. 1 and 2, Astronauts David R. Scott and James B. Irwin completed a record 18 hours, 37 minutes of exploration by traveling 17.5 miles in the first car that humans have ever driven on the Moon. NASA After the joyride of Apollo 15, humanity now was set to explore the more complicated terrains of the Moon, the Descartes region, known for the hills and grooves that cover its terrain. NASA The final Apollo lunar mission, Apollo 17, saw the conclusion of lunar sampling and experiments. This mission is known for being the first time a scientist-astronaut landed on the moon, Harrison Schmidtt. NASA NASA