John David "Moon" Martin (October 31, 1950 – May 11, 2020) was an American singer-songwriter and guitarist. He was given the nickname "Moon" because many of his songs had the word moon in the lyrics. His best known work was "Bad Case of Loving You (Doctor, Doctor)", made famous by the English singer Robert Palmer. His 1982 song, "X-Ray Vision" was an MTV hit music video. He was born in Altus, Oklahoma.