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.
As expected, coming in a range of materials means that there is extensive flexibility with respect to colour choice. Throughout their history the Moon Boot has always been a bright and happy addition to any winter wardrobe and now is no different. Colour examples include neutral and subtle tones such as ochre, grey, dark brown, black and ice through to light pink, violet, azure, petrol blue, orange and sea green. More conspicuous colours consist of silver, ivory, burgundy, bouganville, apricot, red and yellow especially since some also come in a metallic finish.
The astronomers then conducted an analysis called a Bouger correction in order to subtract the gravitational effect of topological features, such as valleys and mountains, from the total gravity field. What is then left is the gravity field hidden beneath the lunar surface, existing within its crust.
With the GRAIL data, the astronomers were able to map the gravity field both in and around over 1,200 craters on the lunar far side. This region--the lunar highlands--is our Moon's most heavily cratered, and therefore oldest, terrain. Heavily cratered surfaces are older than smoother surfaces that are bereft of craters. This is because smooth surfaces indicate that more recent resurfacing has occurred, erasing the older scars of impact craters.