What is the moon made of?
Mike Sutton looks at what we’ve learned about the moon’s chemistry in the 50 years since Apollo 11
On 20 July 1969, Apollo 11’s lunar module landed on the surface of the moon. A few hours later, on 21 July, Neil Armstrong and Buzz Aldrin stepped out. The mission was the culmination of the decade long Apollo programme to take humans to the moon. It was undoubtedly one of the crowning scientific and engineering achievements of the 20th century – but what did we learn about the moon?
During Armstrong and Aldrin’s two and a quarter hours spent outside the module on the moon, they collected around 20kg of rocks and other lunar material. The subsequent five Apollo missions that reached the moon also brought back samples, over 300kg in total.
When the Apollo astronauts returned with their treasures chemists began investigating our satellite’s composition directly. This research still continues, as new analytical techniques are developed and fresh theoretical questions posed.