On Friday, a Russian Soyuz rocket will send an unmanned cargo ship with more than 3 tons of food, water and fuel for astronauts aboard the International Space Station. Russian Federal Space Agency hide caption

itoggle caption Russian Federal Space Agency

During the Apollo 12 mission, astronaut Alan Bean holds a container of lunar soil. The astronaut Charles "Pete" Conrad, who took the photograph, is reflected in Bean's faceshield. Bean says he used to think that in his lifetime, we'd build a base on the moon and start preparing to travel to Mars. Hulton Archive/Getty Images hide caption

itoggle caption Hulton Archive/Getty Images