Escape from Earth

Before a spacecraft can get to the Moon, or anywhere else beyond Earth orbit, it has to achieve an escape velocity of 40,230 kilometres (25,000 miles) per hour. After several false starts, the first US space probe to do this was Pioneer 4 in March 1959. This was the first lunar ‘flyby’ mission, passing the Moon at a distance of around 60,000 kilometres (37,000 miles).