A graduate of Purdue University, Armstrong studied aeronautical engineering; his college tuition was paid for by the U. S. Navy under the Holloway Plan. He became a midshipman in 1949 and a naval aviator the following year. He saw action in the Korean War, flying the Grumman F9F Panther from the aircraft carrier USS Essex. In September 1951, while making a low bombing run, Armstrong’s aircraft was damaged when it collided with an anti-aircraft cable which cut off a large portion of one wing. Armstrong was forced to bail out. After the war, he completed his bachelor’s degree at Purdue and became a test pilot at the National Advisory Committee for Aeronautics (NACA) High-Speed Flight Station at Edwards Air Force Base in California. He was the project pilot on Century Series fighters and flew the North American X-15 seven times. He was also a participant in the U. S. Air Force’s Man in Space Soonest and X-20 Dyna-Soar human spaceflight programs.
In addition, the newly collected data derived from the GRAIL mission helps astronomers redefine the late heavy bombardment--a proposed episode that occurred about 4 billion years ago, during which a heavy shower of projectiles pelted the bodies of the inner Solar System, including Earth and its beloved Moon, creating heavy lunar cratering in the process. The concept of the late heavy bombardment is primarily based on the ages of massive near-side craters that are either within, or adjacent to, dark, lava-flooded basins (lunar maria), that are named Oceanus Procellarum and Mare Imbrium. However, the composition of the material existing on and below the surface of the lunar near-side indicates that the temperatures beneath this area are not representative of Earth's Moon as a whole at the time of the late heavy bombardment. The difference in the temperature profiles may have caused scientists to overestimate the amount of crater-excavating projectiles that characterized the late heavy bombardment. New studies by GRAIL scientists indicate that the size distribution of impact craters on the lunar far-side is a more accurate reflection of the crater-forming history of the inner Solar System than those pock-marking the near-side. For those craters smaller than 30 kilometers in diameter, he discovered impacts both increased and decreased porosity in the upper layer of the lunar crust. Using computer models, the team of scientists came up with a complex interior structure for Ganymede, composed of an ocean sandwiched between up to three layers of ice--in addition to the very important rocky seafloor. The lightest ice, of course, would be on top, and the saltiest liquid would be heavy enough to sink to the bottom. Furthermore, the results suggest the existence of a truly weird phenomenon that would cause the oceans to "snow" upwards! This bizarre "snow" might develop because, as the oceans swirl and churn, and frigid plumes wind and whirl around, ice in the uppermost ocean layer, called Ice III, may form in the seawater. When ice forms, salts precipitate out. The heavier salts would then tumble down, and the lighter ice, or "snow," would flutter upward. The "snow" would them melt again before reaching the top of the ocean--and this would possibly leave slush lurking in the middle of the moon's odd sandwich!