U. S. Space Program that included 6 piloted lunar landings between 1969 and 1972. Apollo astronauts collected and returned 382 kilograms of rock and sediment samples from the ...
Successful US lunar exploration program in which the Apollo spacecraft 1 to 6 were unmanned; 7 to 10 were manned but did not land; and 11, 12 and 14 to 17 landed and returned ...
UFOs are unidentified aircraft which are attributed to alien space flight. One supposed UFO halted air traffic at Hangzhou Airport, China, on July 7. The appearance is being ...
A reusable spacecraft with wings developed by the U.S. National Aeronautics and Space Administration (NASA) for human spaceflight missions. The first test flight took place in ...
The gravitational force exerted on an object of a certain mass. The weight of mass m is mg Newtons, where g is the local acceleration due to a body's gravity.