American rocket expert Robert Goddard famously said: "Yesterday's dreams are today's hopes and tomorrow's reality." It is Robert Goddard's scientific research that gives us the opportunity to realize many flying dreams today. Robert Hutchings Goddard (October 5, 1882 - August 10, 1945) was an American professor, engineer, and inventor, and the inventor of liquid rockets. He established the basic mathematical principles of rocket motion and derived the first cosmic velocity of 7.9km/s required for a rocket to escape the Earth's gravity. He launched the world's first liquid rocket on March 16, 1926. Goddard *** obtained 214 patents, 83 of which were obtained during his lifetime. NASA's Goddard Space Flight Center, established in 1959, is named after him. Goddard Crater on the moon is also named after him.