Life on Mars was released on David Bowie's Hunky Dory album in 1971.
Two years later it came out as a single in its own right. Famous for its exploration of disillusionment and alienation, there is no one single definitive story behind it. But that is perhaps the song's beauty and the secret behind its appeal - that its cryptic lyrics are open to interpretation, and can mean different things to different people.
Musicians and fans talk about what Life on Mars? means to them, and its lasting emotional impact.
Special programme made to mark Bowie's birthday on January 8th 1947 and commemorating his death on January 10th 2016.
And what does the question mark in the song's title mean?
With contributions from:
* Musician Dana Gillespie whose autobiography is Weren't Born A Man * Bowie author Chris O'Leary * Scientist Abigail Fraeman of NASA's Mars Mission * Artist Bridget Griggs * Reverend Steve Stockman * Screenwriter Ashley Pharoah (Life on Mars)
Producer: Maggie Ayre for BBC Audio Bristol
First broadcast on BBC Radio 4 in January 2021.